# First time frame build, with CAD drawing! Would love feedback



## thedudeman (Nov 10, 2006)

Hello everyone,

I've been lurking in this forum for some time now, following the stuck threads, other beginners, etc and now I'm finally going for it! I have access to a nice jig, TIG welder, and have fabricated my own tubing notcher on a metal lathe. I have started making maple tubing blocks, and still haven't decided if I need V-blocks since I can use the jig to mock up the tubing (I think). 
I still need plenty more practice on the thin-metal TIG welding, and the notcher needs dialed in, but in the meantime, I've been working on my plans. I'll post a picture and geometry chart below, along with the tubing I have already purchased. Basically, I've designed a 1x10 (no derailleur or chain guide, 32t narrow/wide ring only) hardtail around a 100mm fork (probably Reba) with aggressive geometry that can be ridden hard. I weigh 220# and I want this bike to be strong and reliable, which is why I'm not concerned about weight. I am interested in any feedback you guys have about anything I have posted here, but I do have some specific questions as well:

•	Is it possible to notch my stays and TIG weld my dropouts, or is it recommended to braze them on a plate dropout?
•	Is this frame ok without ST sleeve? I know it is highly recommended around here, but with a 1.6mm wall thickness on my ST, maybe it's ok?
•	I'd like a little lower standover, would it be safe to drop TT @ ST about 1.5" and add a gusset?
•	With the offset ST, do you recommend any gussets at BB region?
•	I don't have a wheel to measure at the moment, and I settled on 29.25" Dia. for the design; is that about right?
•	With my setup, is my headtube long enough to be strong (105mm)? About ½" between TT and DT
•	Do I need brake support w/ paragon dropouts having the brake mount built into the dropout?

As you can see below, I used the 2d sketch feature in Inventor since BikeCAD wouldn't play nice with my computer, and I'm familiar with the program. So far, so good!















My next steps are to 1. Complete a chainstay drawing to make sure I can squeeze everything in there. 2. More TIG practice 3. Finish tubing blocks.

Thank you guys for any feedback! I already bought materials for this, but if there are any glaring errors, I'm happy to return and buy the right stuff where needed.


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## TrailMaker (Sep 16, 2007)

Hey;

Enjoy the dive!

Noob to noob answers to your noob questions;

1) No reason not to TIG as long as you do not plan to build up or fill a lot. Filling with TIG gets things too hot.
2) .063 should be PLENTY thick for a straight joint. In fact, you might drill and tap them in! 
3) Mr. Walt always said no more than 2" or so of unsupported length above the TT, if memory serves me correctly. You may have some leeway with that thick tube, but no sense pushing your luck either.
4) Probably not necessary, but it certainly couldn't hurt.
5) For me? No wheel = no build. That's just asking for trouble. I take the dummy approach. Once you've done a few dozen, you can slide through on your vast experience with such stuff.
6) I would ALWAYS make my HT as long as I could. I'm uncut steerer size, so it is never a problem for me.
7) No.


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## afwalker (Apr 26, 2012)

Thanks for pointing out that seat tube, I've never noticed it before. The thick section looks like its 75mm long so and inch and a half would still be to the thick part. Tigging the ends of the stays to fill them in does put a lot of heat in them. Sometimes I use a pulse setting of 30pps and lower the heat and build up the filler, then go over it hotter to blend it in. May just be easier to use silver like fillet pro. Those paragons are stainless so no brass.
cheers
andy walker


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## dr.welby (Jan 6, 2004)

I'd probably lean towards at least a 38.1 downtube. Are you designing around the fork sagged?


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## Walt (Jan 23, 2004)

Random thoughts!

-.6mm seatstays are not going to be fun to TIG weld if you are not pretty good at TIG in weird angles/tight corners on thin-to-thick. Get some .8mm or even .9mm if you can find them. 

-I'd go 38mm on the downtube as Dr. W suggests. 

-The 1.6mm seat tube is thick enough to weld directly to BUT keep in mind that if you are throwing lots of heat at it it'll distort a bit more than a sleeved joint will - meaning more work to ream back to vaguely round to get a post in. 

-42cm chainstays on a 29er are not super hard to do but you are going to be cutting things very close on clearance so mock up your chainstay assembly with your actual cranks and ring in hand to make sure you've got something that will work. 

-Yes, you can lower the toptube and add in a brace. Be aware that unless you do it carefully you may end up pulling the seat tube forward at the top and have odd problems with the effective angle/saddle positioning. 

-You do not need any extra bracing for the brake side stays with a dropout-integrated disc mount. 

-Yes, you can slot and TIG, assuming you are decent with the torch. I do it on basically all my frames.

Keep us updated!

-Walt


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## BungedUP (Aug 18, 2003)

A 1.6mm thick Seat tube sounds AWFULLY thick to me. I'm not sure why you'd want it that thick, to be honest. Are you relying on the material thickness to maintain roundness after welding? I'd consider alternately making a heatsink instead, and then honing the bore to fit your seatpost and using a thinner seat tube. With TIG welding, differences in base metal thickness cause as much trouble as anything. Thin to thin is easy, but thin to thick can be more challenging in many cases (though not all), and can cause problems after the fact. 

I'd also consider giving yourself a little more extension on the HT, from the intersection of your DT especially, but your TT as well. Welding the DT and TT will really want to distort the HT when the tubes intersect close to the edges. This is still the case for me, even though I've welded 2-4+ frames a day for many years. 

I second John's (TrailMaker) sentiment about the wheel. It is important to be able to reference the wheel for several reasons. One is simply for proper placement of bends and bridges, but it also is very helpful for alignment purposes. You will want the wheel centered with respect to the seat tube, but also balanced between the seat and chainstays. It is very handy for this, as you can use a caliper to measure between the rim and the stays, and sight down the back of the wheel up through the seat tube and head tube. Furthermore, it would be good to either have the cranks, or know the chainline and where the end of the crankarms sit relative to something you can reference, such as the edge of the BB shell. Sometimes, the crank may sit such that your heel will clip the chainstay if it sits out further than necessary. Having the crank can help you determine whether there is sufficient room for heel clearance (and of course ring clearance).

That is a nice looking design otherwise, and you appear to be well on the way to making an excellent bike. Good work!


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## thedudeman (Nov 10, 2006)

Thanks for the replies everyone! As far as the seattube, I thought it sounded pretty thick as well, but wouldn't a sleeve present essentially the same problems (thick to thin)? 
On the headtube, I think I am going to go longer, and further from the ends to prevent warpage. Unfortunately, when I just throw a 130mm HT into my drawing, my reach and stack get pretty whacked out, so I need to do some thinking geometry-wise there. 

I'll make sure to get my hands on wheels and cranks before going too much further thanks to people's advice here. 

I'm totally up for making the bike stronger by adding a bigger DT, but I have run into another problem: when I add a straight 35mm DT, it looks like the fork crowns may not clear. I can't find a bent 35mm DT that is in stock anywhere. Is there a source for any CAD files on common fork crowns? Seems like getting my hands on the fork sooner than later wouldn't hurt, either.


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## thedudeman (Nov 10, 2006)

dr.welby said:


> I'd probably lean towards at least a 38.1 downtube. Are you designing around the fork sagged?


Looking at working out the DT upgrade. I am not designing around the fork sagged, but I have been keeping it in mind. Do most companies list their static geometries? I have been using bikes that I like to inform my design, but can see the value in designing around sag as well. Do most of you guys do that for front suspension hardtails?


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## thedudeman (Nov 10, 2006)

Walt said:


> Random thoughts!
> 
> -.6mm seatstays are not going to be fun to TIG weld if you are not pretty good at TIG in weird angles/tight corners on thin-to-thick. Get some .8mm or even .9mm if you can find them.
> 
> ...


I'm going to look into thicker stays. Thanks for the suggestion, I can imagine that would be a challenge, especially after my TIG practice session yesterday!

I think I'm going to avoid braces wherever possible, so I may shorten the ST length just a bit, and lower the TT a bit and call it good.

Pretty excited I don't need to brace with those dropouts- I like how they have the brakemount and hanger built in to keep things a bit more simple for my first build.

I will keep you guys updated! Thanks again


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## BungedUP (Aug 18, 2003)

Here's a bent 1.5" DT.

NOVA CRMO 38mm DOWNTUBE FOR MTB/29er WITH BEND :: 38.1mm DOWN TUBES :: ROUND TUBES :: MAIN TUBES :: TUBES STEEL :: Nova Cycles Supply Inc.

I've used it - it's alright.

For entry level seatstays, I'd consider something in the neighborhood of .035". Dead easy to work with in multiple ways - easy to bend, easy to weld, easy to source material. Durable thickness for most types of riding save the most aggressive.

Regarding sagged vs. unsagged, I personally work with the unsagged measurement, just because that's the easiest for me to work with and think about, experience wise. I know what a bike with XX head angle, and XX fork travel/A2C feels like. I _think_ that is most typical, as far as listed figures are concerned.


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## thedudeman (Nov 10, 2006)

BungedUP said:


> Here's a bent 1.5" DT.
> 
> NOVA CRMO 38mm DOWNTUBE FOR MTB/29er WITH BEND :: 38.1mm DOWN TUBES :: ROUND TUBES :: MAIN TUBES :: TUBES STEEL :: Nova Cycles Supply Inc.
> 
> ...


Thanks! That's the DT I wanted, but it's out of stock. I thought the smaller diameter but same thickness would suffice, but I'm going to stick with the advice here and find something beefier. I'll shoot Nova an email and see when they expect to have more.

I'll check out thicker seatstays, maybe even try tackling bending my own? I have access to lots of woodworking tools, so creating a jig and bending them does sound kind of fun- as long as I don't destroy too many in the process! :O

Unsagged is easier for me to wrap my head around as well.


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## thedudeman (Nov 10, 2006)

BungedUP said:


> you appear to be well on the way to making an excellent bike. Good work!


Thanks for the encouragement- I hope you're right!


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## thedudeman (Nov 10, 2006)

*TIG practice!*

So I have the notcher pretty much running well, the only thing that is difficult is getting the height dialed in perfectly. The tubing I'm using for practice at the moment is a downtube off of an old GT Timberline, which claims to be chromolly on the ST badge. Thickness measures at about .030", probably from all the sanding to remove the paint. I'm cleaning it up until it's shiny with emery cloth, then filing the burrs off of the inside, cleaning the cut up slightly with a file, and knocking down the paper-thin outside edges of the cut until they appear to be "normal" thickness. 15CFH argon, with a gas lens, 1/16 tungsten (purple-shop didn't sell thoriated anymore) on an older miller syncrowave (250?), set at around 40 amps.








I'm having a bit of trouble with my puddle wandering on me, and have checked that I have enough argon, and I thought the metal was plenty clean. The other tip was to make sure the machine is on DCEN, which it is. Is there anything else that could cause this? 







As far as penetration, I know the picture isn't great, but does it seem reasonable?


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## RCP FAB (Jun 15, 2011)

Looks way hot for my taste. I purge, but...


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## BungedUP (Aug 18, 2003)

Does your Sync 250 have a pulser? If so, use it. If it does not, I would manually pulse with the footpedal. When pulsing, you will need to set your machine to a substantially higher amperage - how much depends on how you are pulsing. My suggestion is to pulse a higher amperage, for a shorter time, rather than a lower amperage, longer time pulse (however you do it). 

You have PLENTY of penetration there, but you are really cooking your material. Part of that is exacerbated by the short tubing sections, as they have less head sinking capability. Again, my suggestion is to work quickly, rather than slowly. Welding faster often requires more amps, but in the end, the heat input is drastically lower. All that just comes with time and practice, but knowing that moving quickly is preferred over moving slowly might be able to help you out some. 

Try this - If you don't have a pulser, start by running your machine at 85 amps or so. Make your fishmouth cuts, but don't file them back much - you can file the ears back a little where they get really thin, but don't go until they are exactly the same thickness as the rest of the tube. Tack your little practice piece, then start welding by pushing the pedal all the way down quickly, filling the puddle, then backing off to as little as you can without dropping the arc. Then repeat the process, trying to make the second puddle the same size as the first. initially, shoot for doing this around 1 pulse per second. Maybe find some classical music on You Tube at that speed. Practice that for 10 sets or so. You may need to fiddle your amperage on your machine to do this. The idea is that the bead opens up to the correct size (about 3mm or so) at full on, and then you back off to next to nothing as soon as it's the correct width. It will require the most amperage when the joint is closest to 90 degrees. As it backs off to 0 degrees, you will need to either have the pulse on for a shorter time, or not put the pedal fully down. If that doesn't help you any, let me know and there might be some other strategies to try.

For scrap, consider just purchasing tubing from your local steelyard, or from Aircraft Spruce/Wicks. I'm sure there are lots of us around here that have scrap we could send your way as well. Dealing with old paint is crummy business, in my opinion.


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## thedudeman (Nov 10, 2006)

*TIG round 2!*

BungedUP,
My machine does not have a pulser- I wish it did! Thank you for the suggestion! I definitely don't have it dialed yet, but the pulsing with my foot is a cool trick. It just clicked in my head the way you mention it. I've had to weld not-so-good fit up with the MIGwelder, and I essentially do the same thing, and I actually like how it makes the weld look better than the regular old MIG weld.
So anyway, I went and fit up some more joints with less taken off of the ears:







My first try was too hot, or so it seemed as I was welding, so I turned the amperage down incrementally to about 50. In this picture you can see my previous welds, next to my first try at pulsing, which looks like it overheated less. Penetration is still looking excessive too.







Next joint I tried even lower amperage at first, then realized I was compensating by turning it down, not speeding up. So at the very end of my time, I had a good little run of going way faster than I usually do, with amperage at about 60. However, I think I already had cooked the piece by that point.







I feel like the pulsing is helping, because the shoulder and ripples seem a little more consistent. It also gives me a bit of a rhythm to follow, which really helps when me when I weld. I'm excited to get back and do more!
Thanks again for the tip, I contacted Walt about some scrap, and will see about buying some fresh tubing locally.


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## BungedUP (Aug 18, 2003)

Dudeman,

Try spacing your puddles out a little bit. Below is an example of what you might try to shoot for spacing wise. You want to make sure that your new puddle covers the previous puddle's crater, by 25% or so. Sometimes I'll stack closer together, but when learning, it's tough to space things out, and do so evenly. The tendency is to stack puddles closely, and move too slowly, which in turn burns the meat! It's just down to practice really, but I think we can get some improvement to the point that you'll be happy, without too much additional effort.

The pulse action should be quick - like a pedal stab, not so much a foot rock. Imagine that you are Neil Peart or John Bonham playing the bass drum. It might be a tough job to get that down in the beginning - just do the best you can that way. Think "HEAT - mooooovvvvve, HEAT - mooooovvvvveee".

-Peter


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## BungedUP (Aug 18, 2003)

Also, what size filler rod are you using? I'd recommend .045" rod.


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## thedudeman (Nov 10, 2006)

BungedUP said:


> Also, what size filler rod are you using? I'd recommend .045" rod.


I'm using 1/8" er70s- but just ordered 1 lb of mostly .045" weldmold 880 from Walt.
I had one other question- as I was pulsing, I had the torch go out completely a number of times. Is there anything bad about that? It was easy enough to start back up, but I don't want it to mess things up. 
I'll try moving further between each pulse in the morning. Your weld is amazing! I printed it off for motivation and something to aspire to.
Love the John Bonham visual too! I'll try stabbing the pedal- I was definitely just rocking the pedal back and forth.

-Scott


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## BungedUP (Aug 18, 2003)

Hi Scott,

FYI - the Weldmold 880T is, according to Weldmold themselves, 312 MIG wire that they straighten and cut. A coworker and I have been working through some filler rod issues, and received some samples from Weldmold. I found that it does some things VERY well. Particularly, it is very good at filling in areas that tend to be undercut otherwise. It also is a little easier to control than 309L when welding 17-4 or 316 stainless to 4130 type steels. However, I am not quite as hot on it for general purpose welding, though it does ok. It lays flat in the middle of the puddle, but it stands proud at the toes of the weld in many cases, which I don't particularly like. It is a very small amount, and is most likely not an issue for most people. I may change my mind over time with it, but currently, I prefer a good quality (Korean) ER70S-2, and ER70S-6 for welding appearance. Either rod in most cases is entirely sufficient for the joint designs of bicycle frames, though the "880T" theoretically has the higher yield.

I'd try to keep the torch from going out, if you can. Your goal isn't to completely freeze the puddle - You don't want to stack one cold puddle on top of another cold puddle. You want to stack one puddle on top of a cooling puddle, which is most likely largely frozen, but not entirely. It's like the puddle is a jelly filled donut - the jelly is the wet part of the puddle.

What I do really isn't all that amazing - it's just a lot of experience. Most people are capable of that, given time. I've spent a lot of time doing what I do - the amazing stuff is when people like you wade into this for the first time, and come out with something awesome. THAT to me, is where magic happens.


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## thedudeman (Nov 10, 2006)

Mini update: work got in the way, but did get a little practice in on the manual pulsing. No real improvement, since learning to move so far between craters is hard! the welds i did today were worse looking than last time, so i need more practice time I think.

One weld question: I'm noticing some white smoke looking stuff on the inside of the tubes when I'm done welding- what could that be? These are fresh new 4130 tubes, hit with 240 sandpaper on the outside, simple green and rinse inside and out.

Also need to get back to the CAD modifications and will update once I have em.


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## RCP FAB (Jun 15, 2011)

My inside of the tube cleaner/post ream polisher.


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## TrailMaker (Sep 16, 2007)

Ha...

Did the same thing to polish the tapers in my lathe/mill spindles, albeit a bit less artfully, perhaps. I used an old broom handle. A flex hone is nice, particularly if you want to remove a bit more material.


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## thedudeman (Nov 10, 2006)

RCP FAB said:


> My inside of the tube cleaner/post ream polisher.


Thanks! I'm going to see what I can cobble together today. Do you focus on the few inches by the joint, or do you do the whole inside? Also, do you get it where it's shiny like the outside of the metal?


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## RCP FAB (Jun 15, 2011)

I usually just clean the ends to bright metal. Then I clean the rest with alcohol.


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## thedudeman (Nov 10, 2006)

Tubing blocks are done, and got my wheels so I can figure out the rear end clearance, Clarence. 

Re-downtube: Is strength a huge issue with the way I have it set up and my riding style, weight, etc? I'm having trouble a.) locating a replacement tube with a bend that will work, or b.) designing the way I want the geometry around a straight tube. Would a headtube gusset help or am I way off base and really need a beefier front end?


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## thedudeman (Nov 10, 2006)

*More TIG/ Tubing blocks/ inside tube sander thing*

So I got to spend most of today gathering things, and building things and welding to work towards building my frame. It's been a really fun way to spend my free time! Anyway, I got some scraps and .045" weldmold rod in the mail from Walt today (thanks!) and went right to work. 
My mitering jig on the lathe I "thought" was dialed in, but it seems to have too much flex in it, and unless I take over 10 minutes per miter it pings and makes bad noises. So I'm going to try a slight redesign and see what happens. I think it's cantilevered too far away from where the quickchange toolrest attaches, so I'm going to try to get it more centered. Also, I have to figure out how I'm going to get accurate angles. I thought the compound toolrest would work, but when I dialed in a 40* cut to test it tonight, it came out to 50*, which I believe is because the offset from the rotation point of the compound toolrest. I guess I could try the mill, but I don't really want to angle the head for each miter?

So the tubing blocks are so helpful, things aren't falling out of the vice when I try to file. Great idea from this forum!








Rtcfab- thanks for the idea on cleaning the inside of the tubes- it works great! Trailmaker's broom handle idea inspired my "creation" I'm using 80 grit at the moment which seems a little aggressive, but at least it's clean! 








So next was welding some joints together, to what I believe was headtube material. Seemed like a good opportunity to try thicker to thinner metal. I also kept working on the pulsing, which in a couple awesome moments, I feel like I had it. Then promptly burned holes or contaminated my tungsten, or melted off the end of the headtube... The penetration is looking much more acceptable, and I think the thicker headtube could have helped that. Do you guys think the welds are cold enough, or do I need to go faster? I think going to the .045" rod really helped. It seemed like I didn't have to keep the heat up as much when I dabbed the filler material in. 
These are the two sides of the same joints. Any feedback is greatly appreciated!
I gotta say, I was pretty psyched to see my first shiny looking weld!


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## BungedUP (Aug 18, 2003)

I'd say you are making some improvements. Keep practicing - I personally think in the beginning, you are better off welding for an hour, then not welding anymore until the next day. If you do that regularly for awhile, you show more gain than say, welding 8 hours straight (keyword is "regular"). There is something in letting your brain process what you did overnight that I think is more helpful than just strict number of hours total. 

Can you take a picture of the tube coping setup that you have? Maybe someone can help get the setup sorted out from the picture.

P.s. Nice looking tube blocks!


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## afwalker (Apr 26, 2012)

Great looking tubing blocks, the grey sections look a bit hot. The shiny parts are better.
Keep up the practice. Without a heat sink it may be a good idea to weld a section and then turn the piece over and weld on the other side. Your HAZ look kind of wide and that would probably help. I started using this cheap HF piece as a heat sink until I made and bought my own.
Tail Pipe Expander
It's better than nothing and helps control the heat.
take off the rubber bands and maybe use some wire loosely applied to hold it together when you take it out.
Here's a not so perfect weld:







If you notice, it's a little hot on both tubes at the 3 o'clock portion if the top is 12:00, but the HAZ is a bit smaller. This is because that part of the joint is a lap joint and the 12 and 6 is a butt joint. I needed to let off the heat there and will try for better next time.
140amps 30% on time 15% background pulse 1.8pps
cheers
andy walker
Flickr: afwalker's Photostream
Walker Bicycle Company | | Walker Bicycle Company


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## TrailMaker (Sep 16, 2007)

Hey;

Definite improvement in the welds. This coming from someone who knows what they should look like... not like mine. Nice tube blocks! I would think it would be very problematic to miter on most lathes, which I assume are old and variously tired. Rigidity is very difficult to achieve with so many interfaces. Speeds & feeds are tricky on tubing as well no matter how it is done. You might investigate using your mill, something like this.


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## afwalker (Apr 26, 2012)

And maybe try lapping the hole saw and the teeth also,
pic from pvd,








so the saw sits flush and true, and flip it around to either file the teeth or lap them without breaking them. I carefully file with it in the lathe so it doesn't grab the file. You might notice less pinging and grabbing.
cheers
andy walker


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## Walt (Jan 23, 2004)

That tube cleaner idea is awesome! 

Those are head tube scraps, yes. I try to make sure I send a few head tube chunks to everyone who wants scrap because they are good simulations for actual bike joints (and they can double as fake BB shells for practice too). 

-Walt


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## thedudeman (Nov 10, 2006)

So you put it in the chuck and file the teeth as its turning? I tried touching mine up a bit with it stationary (seems like these makita hole saws are all high at the welded seam)


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## RCP FAB (Jun 15, 2011)

I have used lenox hole saws for a few years now. They are a little bit more than the run of the mill ones, but I pull them out of the box, toss them on the arbors and miter tubes. Never had one that didn't work just fine out of the box.


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## afwalker (Apr 26, 2012)

Yep, they have a bit of a bite and that takes the edge off and is cheaper than real annular cutters like Strawberry's. Lennox may work out of the box, but it doesn't hurt to true it up. Until Whit jumps into the conversation, I'll share his pic of the hole saw prep work:







turn it around and just lightly touch off the edges with a file carefully so you hold the file such that if it kicks back it goes away from your hand. The handle away from you. 
cheers
andy walker


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## thedudeman (Nov 10, 2006)

afwalker said:


> Great looking tubing blocks, the grey sections look a bit hot. The shiny parts are better.
> Keep up the practice. Without a heat sink it may be a good idea to weld a section and then turn the piece over and weld on the other side. Your HAZ look kind of wide and that would probably help. I started using this cheap HF piece as a heat sink until I made and bought my own.
> Tail Pipe Expander
> It's better than nothing and helps control the heat.
> ...


Thanks for the tip- there's a HF not too far from here, I'll check out the tailpipe deal.


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## thedudeman (Nov 10, 2006)

*Notcher shenanigans/ more TIG practice*

So here is a picture of my original setup for notching tubing. It was made using the materials available to me, and I machined the lower clamping surface so it is parallel to the angle iron for holding the tube. 








I figured getting rid of one potential area for flex, the quickchange tool holder would be a good start, so I swapped back to the original (turret style?). I also locked the crossfeed while cutting, since I had only locked the compound toolrest previously. Finally, I got rid of the stupid milwakee cutter, and found these cheap ones at the hardware store, made in the USA, with the arbor built in. Not sure if they'll give me enough length for smaller angles, but so far with these tweaks it cuts much better. Still slow, but no popping and pinging. Also tested a 70* angle cut, and checking with a digital angle guage came out perfect, so I'm pretty excited about that!







The headtube joints I was welding measure somewhere between a 1-3/8" and 1-1/2" O.D., so I used the 1-3/8 cutter and used a 10" file to make the joint fit better. I figured a little practice with perfecting joints with a file will come in handy!

Tonight's welding pictured is both sides of the same joints. I have some areas I'm happy with, and the fact that I didn't burn any holes or melt the end off of the headtube is good, but overall heat input seems the same, maybe more in places. It seems like the underside of the DT takes a lot of filler; I thought it went great, but it looks a little undercut in hindsight. 
Which brings me to my current dilemma- sometimes when I try speeding up I'm not able to feed enough filler into the puddle to keep it from getting all flat and overheated. 
I think it's probably mostly just need more practice. Gonna shoot for roughly an hour a day throughout this week.














Thanks everyone for the props on the tubing blocks- it was fun to do something that would help, but was a little easier 

I'm learning a lot- thank you guys for all of your input!
Scott


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## BungedUP (Aug 18, 2003)

Just for clarification - the oxide coloring that you see near a weld is not the same as the HAZ. It's very commonly misidentified as such. The HAZ corresponds with changes in grain structure of the base metal, due to heat. The coloring you see on the metal from welding is where oxides are forming on the surface at fairly low temperatures - from around 400-650 degrees F. 

Think about it this way - the effects of a HAZ are a time/temperature dependent reaction. The colors on the surface of the metal can be dramatically altered by shielding. This does not change the time / temperature aspects, but does change the temperature when the metal is once again in contact with oxygen, which is when the oxides start forming again. The surface oxidation color band is not the same thing as the HAZ. 

With a properly prepped and shielded setup, you can make a puddle, not move the torch, cut the arc, and you should end up without any oxide coloring if you leave the torch in place with a few seconds of post flow. Even though there is no discoloration, there is still a HAZ. You just can't see it, because it's structural change in the metal. 

Sorry for the disruption - carry on!


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## BungedUP (Aug 18, 2003)

Regarding the popping and pinging - I almost guarantee that a substantial portion of that is the fault of the hole saw. Some of the other suggestions about truing the back of the holesaw by turning them in the lathe are good - it does indeed help. 

The #1 holesaw you are after is the Starrett 6-pitch hole saw. You can order them up from MSC, and they will be at your door in a matter of a few days. The next in line are Morse and lenox holesaws, but really, try to get the Starret ones. If you true one of those up, they will cut very well, for an amazingly long time. Additionally, they can be resharpened with a careful hand at the grinder, regrinding each tooth (unless the teeth are broken off). I'd be willing to bet that with the 6-pitch holesaw, you wouldn't detect much difference between the QCTP and the 4-position turret toolpost.

RPM should be in the neighborhood of 300 rpm for typical bike related holesaw sizes. I wouldn't go much above 350 rpm - go lower rather than higher for these.


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## thedudeman (Nov 10, 2006)

BungedUP said:


> Regarding the popping and pinging - I almost guarantee that a substantial portion of that is the fault of the hole saw. Some of the other suggestions about truing the back of the holesaw by turning them in the lathe are good - it does indeed help.
> 
> The #1 holesaw you are after is the Starrett 6-pitch hole saw. You can order them up from MSC, and they will be at your door in a matter of a few days. The next in line are Morse and lenox holesaws, but really, try to get the Starret ones. If you true one of those up, they will cut very well, for an amazingly long time. Additionally, they can be resharpened with a careful hand at the grinder, regrinding each tooth (unless the teeth are broken off). I'd be willing to bet that with the 6-pitch holesaw, you wouldn't detect much difference between the QCTP and the 4-position turret toolpost.
> 
> RPM should be in the neighborhood of 300 rpm for typical bike related holesaw sizes. I wouldn't go much above 350 rpm - go lower rather than higher for these.


I ordered the three main sizes of Starrett hole saws that I'll need today- thanks for the tip! I'll face the back of them when they get here. I also had my spindle rpm down to about 90. Bumped it up for todays cuts to around 250 and it seemed to cut just as well, but I was able to feed the tube through quicker.


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## thedudeman (Nov 10, 2006)

TrailMaker said:


> Hey;
> 
> Definite improvement in the welds. This coming from someone who knows what they should look like... not like mine. Nice tube blocks! I would think it would be very problematic to miter on most lathes, which I assume are old and variously tired. Rigidity is very difficult to achieve with so many interfaces. Speeds & feeds are tricky on tubing as well no matter how it is done. You might investigate using your mill, something like this.


I like that idea, but don't think I can afford a vice like that. Seems like I'm getting the kinks ironed out of my lathe setup, but this is definitely a possibility; or just doing it with a hacksaw and file if I have to!


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## thedudeman (Nov 10, 2006)

*More TIG*

With the hole saw setup working decently, I was able to semi-quickly prep my joints for tonight (and the fact that one of the "notches" was already cut from this scrap by Walt). I moved where I'm welding to a higher, more comfortable table which was a nice change.

I almost feel like I've taken a step back, but I'm not sure. No holes in the welds, but I did weld my tungsten to the metal for my first time ever. 
I was having trouble with my Tungsten becoming contaminated when I don't think I had actually hit anything. 
I've been clipping the end of my filler each time I start up again (since I have the bad habit of removing it from the argon immediately). Argon is at 15 cfh, and things are cleaned to bright metal inside and out. Sprayed with simple green, scrubbed then rinsed and dried really well. I really have no clue what is causing it. Any ideas? The only thing I can guess is that I'm closer to the puddle than I think.

I really need to practice keeping my torch angle aligned with where I'm at on the tube. I kept melting off globs of welding rod inadvertently which kinda ruins my whole flow. I believe this is BB material welded to .035 (angled tube) and some sort of very thin butted material through the pierced hole. Not super proud of these guys, but maybe I can learn something from them:


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## TrailMaker (Sep 16, 2007)

Hey;

Your first time dipping the electrode? I'd almost call you a liar on that one.  That's usually the first thing anyone fuses to a tube! Yes, the filler can jump to the electrode if you get an amperage spike, hit an irregular spot, waver in your position, dip at the wrong time, or just get too close. I find that I cannot weld very much at all without having myself braced against the work, and that makes it very difficult. The hardest part from my perspective is being able to roll with the contour of the joint as you weld. Any movement on my part and I lose my distance from the work and my weld wanders.

Practice...

Understand that - in the extreme - all that fancy welding Peter and others can do does make a variously theoretical if not practical difference, but what you are doing now will glue a bike together, and it will probably hold and last to a reasonable degree. Yes, good welding is more structurally viable in the extreme, and overall will be more reliable and long lived, but at a certain point just becomes eye candy and a point of pride for the craftsman. For the rest of we schlubs, well, thankfully, you can make a bike without it. Don't get too hung up on it and let it get in the way of building your bike!


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## dr.welby (Jan 6, 2004)

thedudeman said:


> I also had my spindle rpm down to about 90. Bumped it up for todays cuts to around 250 and it seemed to cut just as well, but I was able to feed the tube through quicker.


At least with a belt drive machine going to higher RPMs means lower torque, which might reduce the tendency of the cutter to dig in and snag. You'll have to feed slower to keep the MRR in the same range.


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## thedudeman (Nov 10, 2006)

Oh I've contaminated my fair share of tungsten from hitting the puddle! Hahaha, this is just the first time I had to undo the collet, pull my torch off, then break the tungsten off my metal. 
I didn't know filler could get on the electrode from amperage spikes or irregularities...

Thanks for the encouragement- I'm going to still try and hit my goal of an hour a day for the rest of the week and see what happens. Looks like the starrett hole saws will be here tonight- that was sure fast!


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## RCP FAB (Jun 15, 2011)

I don't know about the starrets but the lenox (better than starrets IMO) come in 1-7/16" for perfect head miters. Also 1-3/16" for ex butted seat tubes.


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## TrailMaker (Sep 16, 2007)

Hey;

I've had one bad experience with the new design Lenox hole saws. They've changed the design of the slots in the side, hyping them as easier to dig the discs out of or something. I've worn out dozens of the old style straight slot ones, but the FIRST TIME I used one of the new ones, the edge of the angled slot threaded itself onto the edge of the part I was holing and mangled the hole saw, within 10 seconds of hitting the trigger. Pissed me right off. The new design is an answer to a question I was not asking. Your results may vary, but I'm not impressed.


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## RCP FAB (Jun 15, 2011)

Could have been a bad one with a lip on the edge of the slot or something. I've literally used 250-300 of the new style ones over the years with no real issues.


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## BungedUP (Aug 18, 2003)

thedudeman - don't worry one bit about going backwards. It's not really going to happen if you regularly practice. As much as humanly possible, take the desire for what you want it to look like, vs. what it does look like out of the equation. Sometimes it gets better, sometimes it appears to get worse. The big picture though is that practice = overall improvement. It is what it is, and it WILL get better with practice. Don't sweat what happened tonight, vs what happened last night. Try to just enjoy doing it (which you very well may be). 

Much of the process of improvement happens at a subconscious level. Initially, most of the improvement will just happen, and you won't understand why it gets better (you may not even be able to tell what you are doing now that you weren't doing before). 

John is right as well, that what you are doing now will hold a frame together.

-Peter


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## BungedUP (Aug 18, 2003)

Ok, so I'm looking at some of your pictures, and trying to figure out anything that might help you. 

Your base metal is overheating in part due to it's small size. Small chunks are going to heat up quickly, and then can continue oxidizing long after your shielding gas is removed. These oxides can interfere with welding, and stainless fillers are more difficult to control once this happens. I wonder if I'm seeing a little of that in your weld bead. In order to try and wet out a stainless filler on an oxidized metal surface, you need more amperage. Thus, you either don't get the puddle profile you want (poor wetting out), or you put more amps down and all of a sudden the puddle opens up and now you are looking at Lake Superior! 312 or 880T isn't as bad as some that way - it's better than 309L in that regard, but your regular old ER70S# doesn't behave that way. Once you get closer to welding your frame, you could switch back to the 880T if you were wanting to use that.

You might try .045" ER70S-2 or 6 filler, and see if things get a little easier. The bead won't be as shiny, but you may have a more consistent shaped bead. Once you get closer to welding your frame, you could switch back to the 880T if you were wanting to use that. Alternatively, you might keep the total temperature of your work down by giving it time to return to ambient temps, or cleaning the oxides off with a brush or some such. You could also come up with a heat sink of some sort. 

Just a few thoughts, but don't think about them too much.


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## thedudeman (Nov 10, 2006)

*...more TIG, I promise I'll start the frame soon!*

Peter- 
Thanks for taking the time to give feedback! I didn't know that stainless was sensitive to the oxides that are forming, so tonight I really made a point of just stopping instead of trying to power through if things were going south. What you said about it not wetting in, then just turning into a lake was a perfect description of what I've experienced when I really overheat things.

I was looking at some heat-sinks, and I think that's something that I can do without too much trouble, so I'll probably go for it soon.

I was having trouble holding onto my parts before and noticed that you and others have used a bike stand to hold frames, so I got my park stand out and took off the rubber pads to avoid melting them, and it was so much easier to get to each part of the joints!
I tried to take your advice to just not get hung up in how each individual weld looks, and to enjoy myself and keep practicing. I'm thinking that Slayer I've been listening to probably wasn't the best soundtrack for welding, so I went with some more mellow tunes and took my time.

The other thing I tried was to weld a little bit, flip it, weld some, pause to let it cool, then start again. I had been just wrapping around the entire joint, but I liked this better.

I only had one major overheating tonight, and it happened at the bottom of my first DT/HT junction:








On my second DT/HT junction, I welded the bottom first, while the metal was cold, which seemed to help quite a bit in keeping the heat down, but I think heat sink will be pretty helpful here too: 















I think next is continued TIG practice on some CS and SS type joints, sorting out my DT/geometry problem, and getting some heat sinks built or rigged up from Harbor Freight!

Oh yeah, on these joints, the tube welded to the headtube is cut off when I'm done to use for another joint. Usually it's about 4-5" long while I'm welding.

Thanks again!
Scott


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## BungedUP (Aug 18, 2003)

Scott - that middle welding picture shows H U G E improvement! Overall, I can see the overheating is going way down as well. Keep at it.

One thing that worth mentioning is to make sure that your amperage is set high enough that you can create a good puddle in about 1 second. If it takes a few seconds, you aren't using enough amperage to get consistency in your weld bead. I can't remember what you were using, amperage wise, but I'd make sure you can get a good puddle that wets out quickly with you amperage setting. If you have to work it into the base metal with time, rather than more pedal, you don't have enough. 

Great job!
-Peter


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## thedudeman (Nov 10, 2006)

Thanks! I think the hour a day practice is helping!
I have worked my way up to around 80 amps, which if I remember to step on it enough will establish the puddle pretty fast. I still find myself wanting to slooowly build the initial puddle, I guess out of habit!


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## BungedUP (Aug 18, 2003)

80 sounds plenty. I couldn't remember if you were using around 40 or had worked up to more. 

Getting the puddle going quickly is good for heat control. Overall heat input is amps x time, so taking longer than necessary to get the puddle up to size is just heat that starts flowing into the surroundings and it builds up. 

I'll shut up now!


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## afwalker (Apr 26, 2012)

Wow, nice to see such improvement! That "patience grasshopper" approach is working.
You're doing great and really making great strides. Wish my first welds were so pretty.
cheers
andy walker


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## TrailMaker (Sep 16, 2007)

Indeed;

The whole thing is looking better. A more well defined, narrower HAZ, and the colors are coming into range nicely. I can see you are having some difficulty at times with the "ears" of the mitered tube. This is typical. You need to focus more heat into the HT (or larger/thicker "host" tube) at this point to decrease the tendency of melting the tangent exposed edge of the mitered "guest" tube. When you are welding in areas of lesser angle, it is easier to get the arc to visit both surfaces, but out in the flush range of the joint (approaching parallel), the arc always wants to escape to the mitered tube, which often melts it.

I'm way better at talking about this than doing it....


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## thedudeman (Nov 10, 2006)

afwalker said:


> Wow, nice to see such improvement! That "patience grasshopper" approach is working.
> You're doing great and really making great strides. Wish my first welds were so pretty.
> cheers
> andy walker


Andy- Well thank you- now I gotta keep going so I can be consistent! 
Scott


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## thedudeman (Nov 10, 2006)

TrailMaker said:


> Indeed;
> 
> The whole thing is looking better. A more well defined, narrower HAZ, and the colors are coming into range nicely. I can see you are having some difficulty at times with the "ears" of the mitered tube. This is typical. You need to focus more heat into the HT (or larger/thicker "host" tube) at this point to decrease the tendency of melting the tangent exposed edge of the mitered "guest" tube. When you are welding in areas of lesser angle, it is easier to get the arc to visit both surfaces, but out in the flush range of the joint (approaching parallel), the arc always wants to escape to the mitered tube, which often melts it.
> 
> I'm way better at talking about this than doing it....


Thanks for the tip on the ears- I was wondering about that- on some of these I have been consciously backing off the amperage trying not to overheat it, but it looks like when I do that is when I have trouble with the weld just sitting on the ears instead of going on to the headtube as well.

Unfortunately I had to take the night off of welding tonight but I did start tinkering with how I'm going to clamp and miter my chainstays to the BB. Saw some cool horizontal mill attachment setups that I'd never even considered for mitering tubes that have my gears turning.


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## TrailMaker (Sep 16, 2007)

thedudeman said:


> I like that idea, but don't think I can afford a vice like that. Seems like I'm getting the kinks ironed out of my lathe setup, but this is definitely a possibility; or just doing it with a hacksaw and file if I have to!


Hey;

I forgot to mention that this vice cost me about $35! Fleebay special. It did not look that nice when I got it, but the bones of it were excellent - seen through the light surface rust and gunk - and all it needed was cleaning up. I bead blasted and rattle canned it. It seems plenty rigid so far.


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## thedudeman (Nov 10, 2006)

*Starting a CS/SS fixture:*

I've had a little break from TIG due to work and family obligations, but since for my next TIG practice joints I want to simulate CS and SS joints, I figure it's a good time to figure out how I'm going to cut those joints when the time comes. I don't have it completely figured out, but sometimes I do better just putting everything I have in front of me and seeing what I can come up with. I'm attempting to make a jig where I can notch my CS and SS's in pairs. Today I put together a rough fixture that will hold the BB end of the CS's. 
I think for the ends that will hold the dummy axle, I'm going to have to mill a block of aluminum to hold things.
I've also seen a picture of a fixture that had a big piece of aluminum roundstock to simulate the tire, so I think I'll do something like that, but maybe just out of wood. 







Ideas? I picked up some hardware to bolt this thing together, so I'll see what I can do tomorrow. 







The main thing I am unsure of right now is how to get the correct angle between the cutter to the seat stays? Digital angle gauge? Fancy protractor? 
Oh yeah, I'm considering having the main support beam off to the side so I can more easily clamp this thing in a vice for the chainstay cut.


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## thedudeman (Nov 10, 2006)

*Quick update*

First thing is, 38mm 9/6/9 bent 29er downtubes are in stock at Nova, I finally got ahold of them, and they had about 80 of them, but simply were listed "out of stock" on the website. The lady there was very helpful, and it may seem small, but it feels like a big deal to me because completely solves my design dilemma. Bike will be stronger, and I know my fork that I don't have yet will clear the DT!

Also got a longer (115mm) HT on the way so I can keep those tubes away from the ends!

I haven't had a chance to dive into working on the chainstay jig any more, but was curious- would I be better off simply using a template program and hand-cutting/filing these this time around? I feel a bit overwhelmed trying to figure out how I'm going to cut the stays, which end first, and how to notch them without messing up.

Almost out of DT/TT practice material, but here's tonight's practice. Was focusing on getting ears better- pictured side is better, other side was too far into the DT material. Was forced to take a few days off, but I think the time off was a good thing. Plan is to keep practicing to get my consistency better. Finally, I'm pretty excited that I didn't contaminate my tungsten at all tonight!


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## Walt (Jan 23, 2004)

Looking fantastic! IMO you are ready to build a frame (assuming you can replicate that consistently)!

-Walt


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## afwalker (Apr 26, 2012)

Very good improvement, really looking better. I hope some others give some tips on the stops/starts, but what I do on a restart is bring up the heat slowly, and may even back up a "dime" or two, with no filler yet and gradually get the puddle as wide as the weld, then start moving. You still will see the start/start, just they should blend in more. Add filler on the new section. 
You may want to try the miter template first rather than work out the bugs on a jig.
Expect to waste a few stays dialing the new jig in Just have backups ready if you do.
cheers
andy walker


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## TrailMaker (Sep 16, 2007)

Welds are looking good!

There's no reason you could not do your mitering by hand the first time. Not sure that angle iron v-block setup is rigid enough for machining. Hole saws are really chattery/grabby and can wreck a setup that is not pretty well fixed in place. Stare at my stay setup for a while and then ask questions that perc up in your mind. This was created some years ago by _The Professor_. He has since moved on to "better designs" by his estimation, but this rig has performed very well since it has been in my possession. I added the dummy tire holder and the vice block that allows mounting on the mill both horizontally and vertically, in either the flat or angle vice. I find it exceptionally verstaile!


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## JaquesN (Sep 14, 2009)

Advice from a relative noob (~15 frames)

Re your chainstay setup, I spent a while working on mine and I'd suggest just setting that aside for now and hand-mitering. Once you build a frame or two you will have a better sense of what you need. Think about how you are going to hold the stays for tacking instead. As Trailmaker alluded to, it's real hard to get the thing rigid and lined up enough to make it a time saver over hand mitering, especially for a one-off project.

You seem to be a pretty good fabricator so maybe you will have better luck.

Jim


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## ktm520 (Apr 21, 2004)

Nice welding man. You are making much better progress than me, though I haven't had much time to practice since I recently got the welder running.


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## G-reg (Jan 12, 2004)

You'll pull out a ton of hair hand mitering stays.....But you'll learn a ton about how those cuts need to happen, and time come to use the cool toys you'll have greater understanding of what's going on.


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## thedudeman (Nov 10, 2006)

I kinda figured the silent streak with respect to the chainstay "fixture" was a sign. I'm gonna take the advice here and do this rear end by hand until I have time to build a proper fixture. 
Excited/ nervous to actually start mitering my main tubes. Biggest obstacle now is keeping the miter cuts in the proper rotation or timing? with respect to each other. After trying unsuccessfully to figure it out myself it's time to do some research. 
Thanks again everyone for the suggestions. What an amazing resource here- I am very grateful- this is pretty much something I have dreamed of doing doing for waaaaaay too long. Kicking myself for that, but having an absolute blast and so happy to actually be jumping in.


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## G-reg (Jan 12, 2004)

I pony'd up for BikeCad Pro pretty early on in my hack-ery. Being able to print out really accurate mitre templates was (still is) a huge crutch. Scribe a line the length of the tube, any bow or on purpose bending will determine where this line is. Properly line up the mitre templates with that scribe line and you're 90% there. Depending on what type of fixturing you have available can solve those problems too.


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## TrailMaker (Sep 16, 2007)

Hey;

If you were not aware, a toolmaker would use a height gauge on a surface plate.










Set the tube in your mill vice. Use anything suitable as a riser block to get your pen at the right height. It does not have to be on the tube centerline. Lay your Sharpie on the block and scribe a line on either end of the tube. Same idea. Simple. Done!


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## dr.welby (Jan 6, 2004)

thedudeman said:


> I kinda figured the silent streak with respect to the chainstay "fixture" was a sign. I'm gonna take the advice here and do this rear end by hand until I have time to build a proper fixture.


It's pretty close to what I use, with the exception that my top clamping piece is more rigid and I clamp it over 3 threaded rods. I don't have any problems with rigidity and cutting - it cuts the stays like any other tubing block. For accuracy, in the two times I've used it I've had to make a minor adjustment with a hand file to one of the stays, but I haven't tracked down where the error is coming from. My dummy axle is pretty crude so I think that's my first suspect.


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## JaquesN (Sep 14, 2009)

Again, maybe I'm just not good at jig making, but I built the exact same thing, right down to the 8020 and welded V-blocks, and it was too inaccurate for anything but a rough cut.

The stays would twist and move sideways as the cutter hit them. The Vs just didn't seem to keep them in place well enough.

I've since invested in a set of chainstay blocks from Alex Meade, but haven't used them yet.


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## TrailMaker (Sep 16, 2007)

For what it's worth;

Given a mill at your disposal, tube blocks are pretty easy to make. I've just used the appropriate size of center cutting end mill and bored a hole right through. Accuracy has been far better than necessary even with no fuss taken. I have always used a slitting saw to halve the blocks, but some just band saw them.


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## BungedUP (Aug 18, 2003)

For making fixturing blocks of various kinds, you can do as John suggests, but instead of splitting a single block, you can start with 2 blocks clamped together, which when separated, become the two halves. If you insert some paper between the 2 blocks before milling, there is a little room for compression as well. 

$.02

P.s. the tire block system such as what John developed really adds a lot to the stability for mitering stays. Additionally, they can be used to estimate tire clearance, and do some error proofing of your setup, ensuring you DO have the required space you need.


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## RCP FAB (Jun 15, 2011)

Call me lazy, but for $12-18 I'd rather just buy them from paragon. Even assuming you have all the tooling, you have to buy the aluminum and hardware, rough cut, face, drill and tap, center, bore, and part them. When you are done you have spent half the money as they cost and they aren't as nice (tumbled and engraved).


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## TrailMaker (Sep 16, 2007)

OK;

Yur lazy!  I just take every opportunity presented to use my machines to change the shape of metal. At my level, it seems I always learn something every time I do, and I enjoy it! YMMV, of course. The only thing I don't enjoy is sweeping up!

Something else I've seen some people do is machine miter their CSs with no support for the DO end of the stay. This makes little sense to me. Given how grabby hole saws can be, and the vibration they create even when cutting perfectly, I want my DOs tacked in place and my dummy axle installed to stiffen and triangulate the whole show. Beyond keeping everything in place, the extra rigidity must cut down on vibration significantly.


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## thedudeman (Nov 10, 2006)

dr.welby said:


> It's pretty close to what I use, with the exception that my top clamping piece is more rigid and I clamp it over 3 threaded rods. I don't have any problems with rigidity and cutting - it cuts the stays like any other tubing block. For accuracy, in the two times I've used it I've had to make a minor adjustment with a hand file to one of the stays, but I haven't tracked down where the error is coming from. My dummy axle is pretty crude so I think that's my first suspect.


Cool, some good improvents over mine! Maybe I can make it work for this frame. I'm pretty much exclusively focused on the front triangle right now, but I'll come back to this. Thanks!


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## thedudeman (Nov 10, 2006)

*I have offically started the frame!*

So since I received my new tubes (38mm DT, .8mm thick SS, and 115mm long HT) I spent some time this weekend updating my drawing. Adding in the longer HT did strange things to my geometry, so I revamped it a bit to maintain the reach that I wanted. I also slackened the ST angle out to 75 degrees, which I think is still pretty steep, especially since I will likely be running a zero offset post. Most of these changes are input from the people on this forum, so thank you for your help! Below are my updated geometry, tubesets and drawing. I'd still love feedback, but some things will be harder to change at this point.
Updates in geometry or tubing are highlighted in yellow:














Next is the headtube detail. I got a longer headtube so I could space my TT and DT further from the ends (1/2" now), hopefully it's enough! I wanted to maintain a decent gap between the TT and DT for strength an to increase the probability I will be able to do a good job welding in there! 








And now for what I did today: I got my full size print from kinkos (idea from this forum), and got my seatube cut! 














I'm excited because the angle and length came out near perfect, and the paragon arbor plus the starrett cutter worked very well! (almost no chatter , and a smoother final product) As far as timing my cuts with each other, I like the idea of taping the cutouts to the tube, but I need to figure out a good way to reference a center line off of my jig. Maybe an easier way would be tubing blocks and a mill, but I would like to make this setup go if possible. I like that it self centers and has "easy" to dial in angles (if I'm not re-checking myself multiple times).

I think I had more questions, but I am super tired, and already accidentally deleted a more well-written version of this post!


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## thedudeman (Nov 10, 2006)

PS- typo on the seatstays, they're 16mm tapered, .8 thick, straight. Ordered two sets so I can try to bend em myself!


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## BungedUP (Aug 18, 2003)

thedudeman said:


> So since I received my new tubes (38mm DT, .8mm thick SS, and 115mm long HT) I spent some time this weekend updating my drawing. Adding in the longer HT did strange things to my geometry, so I revamped it a bit to maintain the reach that I wanted. I also slackened the ST angle out to 75 degrees, which I think is still pretty steep, especially since I will likely be running a zero offset post. Most of these changes are input from the people on this forum, so thank you for your help! Below are my updated geometry, tubesets and drawing. I'd still love feedback, but some things will be harder to change at this point.
> Updates in geometry or tubing are highlighted in yellow:
> View attachment 877507
> 
> ...


To index the cuts, you can use a tube that is the same size as the first cut, then place a bubble level on the tube (either flat on the end, or parallel with it) to orient the second cut.


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## thedudeman (Nov 10, 2006)

BungedUP said:


> To index the cuts, you can use a tube that is the same size as the first cut, then place a bubble level on the tube (either flat on the end, or parallel with it) to orient the second cut.


That is awesome- can't wait to try it! Excited to get this front triangle together. Thank you!


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## dr.welby (Jan 6, 2004)

You can C-clamp one of your tubing blocks in the center of the tube for reference. Or here's a cheapo phasing block:


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## TrailMaker (Sep 16, 2007)

dr.welby said:


> You can C-clamp one of your tubing blocks in the center of the tube for reference.


Pffff...

I was trying to remember exactly how I did it myself. Tube block of course. Feeble mind. Thanks for reminding me!


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## thedudeman (Nov 10, 2006)

*Downtube is a success! Top tube question please.*

Thanks for the ideas on the blocks- I thought of using my maple blocks, but still ran into the problem with nothing to reference off of my tube cutting setup. Luckily the level idea worked. My levels were so whacked out that I used a digital angle gauge, and it worked! I zeroed it off of the top of the chuck, and used the headtube and the gauge to get 90* for my BB cut. So far so good! Things fit up pretty well in the jig, accept my seat tube arrangement took some guessing and checking, but it's pretty much there now. Fit ups are looking really nice so far, and I was really excited to see if I could get the whole front triangle cut out, but then I ran into a potential problem.

Here's my question:
For my top tube, the absolute shortest it will be, at the deepest part of the notches is *540mm*. I'm using the nova 35mm 9/6/9 downtube for my toptube. I got the length of each butted end off of the website (80 and 150mm).

The distance between where the butts end is roughly *520mm*. If the deepest part of my notch cuts come in at 540mm apart, 







that leaves about 10mm of thick material on each end (at the shortest points only). 
Sticky note is on the ruler at the shortest point of the cuts, and the sharpie lines on the tube are where the butts end:








So is 10mm of butted material on each end enough? I know that internal butts taper-are the tapered portions typically included in the butt length?

It's on hold for the moment while I figure this out- hopefully I don't have to make another order, but if I do, I'm happy to have the opportunity to fix things before this frame is permanent.

Finally, my frame design has this anvil jig almost maxed out- glad I'm not building any bigger! it's funny seeing it come together, it looks like a massive old-school GT performer!
Like this one


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## Eric Malcolm (Dec 18, 2011)

Have you measured correctly? - 420mm TT seems way too short for the drawings given. That cut tube should be a little under 600mm.

Eric


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## thedudeman (Nov 10, 2006)

Eric Malcolm said:


> Have you measured correctly? - 420mm TT seems way too short for the drawings given. That cut tube should be a little under 600mm.
> 
> Eric


Hi Eric,

Thanks for catching that! I just double checked and that length was a typo...

So I still have the same problem/ question- is 10mm of butt on each end enough? 
I corrected the numbers on the previous post, and added a picture for some more clarity.

Scott


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## briderdt (Dec 14, 2012)

I would suggest measuring the butts yourself to make sure. Sometimes the tubes are marked on the wrong end, sometimes the butts aren't quite where they're advertised to be. With only 10mm to play with, you could be getting into the thin section rather easily. Making a butt gage isn't that hard -- I used some scrap steel and a $15 dial gage and fabbed up one in a couple hours (including a lot of hemming and hawing about which pieces to use, getting it lined up, soaking off the flux...).


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## afwalker (Apr 26, 2012)

Straight guage? or this maybe BikeLugs.com
it's 35mm 1.2/0.8 and $11. Don't know if there's a minimum order. Put the thicker end on the headtube.
cheers
andy walker
Walker Bicycle Company | | Walker Bicycle Company
Flickr: afwalker's Photostream


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## Eric Malcolm (Dec 18, 2011)

thedudeman said:


> Hi Eric,
> 
> Thanks for catching that! I just double checked and that length was a typo...
> 
> ...


Scott

I checked the tube out on the Nova site to better understand your question. So you are using a 750mm Down tube for your TT. At 35mm, this has good surface area and diameter strength in a general engineering sense, but I am concerned at the head area being a little too short for its end use. On a road bike -yes, wary on a MTB. I think you would be better advised to look at Nova's 31.7mm (9/6/9) DT at 680mm long with 100mm and 150mm butts. Perhaps 40-50mm at the head tube end would be better, more if possible. Note, it is not so critical at the seat tube connection to have .9mm wall, and you can play with the tapering section down to .6mm OK, at 35mm, you have a bit of insurance up your sleeve, but you've got your Tig skills up to working at .9mm, .6mm could be a different matter.

Your call.

Eric


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## thedudeman (Nov 10, 2006)

I would love to measure the butts- but didn't know you could! I'll do some checking on how to do that. I cut the tube this morning, front triangle is successfully together. Managed to stay in the .9mm tubing at both ends all the way around.

Is it important to have a longer thick (butt)section at the ends for strength, or is it all about weldability/ stronger welds with thicker joints? I can't imagine the tube bending or breaking where the butts taper, and if I'm at full thickness on each joint is there a reason I'm missing to have a longer section of thick material?

Number one thing is to make the bike safe and strong, so if a longer tick section at each end is necessary I'm happy to order it.


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## BungedUP (Aug 18, 2003)

thedudeman said:


> I would love to measure the butts- but didn't know you could! I'll do some checking on how to do that. I cut the tube this morning, front triangle is successfully together. Managed to stay in the .9mm tubing at both ends all the way around.
> 
> Is it important to have a longer thick (butt)section at the ends for strength, or is it all about weldability/ stronger welds with thicker joints? I can't imagine the tube bending or breaking where the butts taper, and if I'm at full thickness on each joint is there a reason I'm missing to have a longer section of thick material?
> 
> Number one thing is to make the bike safe and strong, so if a longer tick section at each end is necessary I'm happy to order it.


dudeman - (what's your actual name- I feel funny calling you that all the time)
I think you will be alright with what you've got. The butt 's primarily there for weldability and joint strength,which you've got an adequate amount of. It sounds close, but I think you'll A OK.

furthermore, you can hold a tube up to a bright light, and with a piece of welding rod inserted into the tube, you can get a pretty good idea as to the position of the butt/transition (using the rod as a depth gauge)


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## thedudeman (Nov 10, 2006)

*Front Triangle!*



BungedUP said:


> dudeman - (what's your actual name- I feel funny calling you that all the time)
> I think you will be alright with what you've got. The butt 's primarily there for weldability and joint strength,which you've got an adequate amount of. It sounds close, but I think you'll A OK.
> 
> furthermore, you can hold a tube up to a bright light, and with a piece of welding rod inserted into the tube, you can get a pretty good idea as to the position of the butt/transition (using the rod as a depth gauge)


Hey Peter, my name's Scott- and thanks again for the input!
I'll try that trick for checking out butted sections tomorrow.

If I can get away with this tube safely, I'll have a very light-weight double butted top-tube at least! This has been a great learning experience. Things like ordering the right tube length, AND accounting for butted portions of tubes ahead of time. the input helping me sort out my rookie mistakes is truly appreciated.

I'm pretty excited that the front triangle is together. I've been working on this with most of my free time, but the plan is to start hitting the practice welds a lot again while I figure out fitting up the rear end. Looking at my notching jig today, I am thinking of doing the CS to BB one at a time. Then probably hand-filing the remainder of the joints. 
Anyway, here's what I have so far:







I got so excited to have the front triangle together, I went to roll it around and the TT fell out, pinged off of something on the fixture, then bounced three of four times on each end like a baton.... I gasped and just watched it happen, like a baby falling out of a stroller. Small dent on the underside of the TT, and bent the ears of my joints in slightly. Luckily I was able to tap them back out and re-file them to perfect, but still! :eekster:


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## DSaul (Dec 13, 2012)

This is my quick and dirty tubing butt checker. Just some conduit and a Harbor Freight dial indicator. Pay no attention to the crappy welding, I fillet braze my frames.


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## thedudeman (Nov 10, 2006)

Thanks for the pictures of your gauge- looks like something I could try to replicate in the future! 
I didn't do a whole lot on the frame tonight. I cut my seat tube slot, and did some research on my bottle boss and cable guide silver soldering.


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## BungedUP (Aug 18, 2003)

DSaul - Brilliant! Simple, cheap, functional, and hard to misread. I love it.

Scott, don't feel bad - you wouldn't believe how often you hear tubing getting dropped in a professional shop. It's just ridiculous some days. The worst is when you try to grab it, and knock it 15 feet further than if you had just left it alone.


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## TrailMaker (Sep 16, 2007)

Let me show some ignorance;

I have zero experience with butted tubing. By the clever dial indicator method, I must assume that all tubing is externally butted? 

Ha! There are some days when I just give in and throw a whole bunch of stuff on the floor on purpose, in some variously vain attempt to appease the gravity gods. I think it actually works... once in a while. The bike is looking great! Pretty fancy jig for a first frame there, Scott. That's really cheating... you know...


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## DSaul (Dec 13, 2012)

The tubing is internally butted. I have a small bead of weld to raise the tube up off the conduit for an accurate measurement.









Thanks,

Dave Saul


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## briderdt (Dec 14, 2012)

Mine is brazed, so I just dropped a dab of brass there for the same purpose (and my slider tube is much smaller).


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## thedudeman (Nov 10, 2006)

TrailMaker said:


> Ha! There are some days when I just give in and throw a whole bunch of stuff on the floor on purpose, in some variously vain attempt to appease the gravity gods. I think it actually works... once in a while. The bike is looking great! Pretty fancy jig for a first frame there, Scott. That's really cheating... you know...


Hahahah! I will try the throwing stuff on the floor on purpose trick- I'm sure it could be a nice outlet 

Thanks- I'm pretty excited about how the frame looks- and I am extremely lucky to have access such a nice jig. Problem is, I'll probably come away thinking I need one of my own!


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## thedudeman (Nov 10, 2006)

*mini update*

So things have been busy at work and home, and I haven't done a whole lot in the past week. The one thing I did do is track down my Reba fork, and next is cranks so I have these items to test-fit when the time comes.

So here's my current agenda:

1. Learn to silver braze so I can do my bottle cage mounts. I did the holes in my DT and ST and I read on Anvil's framebuilding guide to braze before welding. Do you guys recommend doing cable guides before welding, as well? Is my hardware store product here going to cut it? (got advice from a plumber friend to try the local welding shop, but they weren't open so I grabbed this):






oh and I have an oxy acetylene setup I can use for this.

2. Tack weld front triangle together! This is one I'm concerned about. Here's my plan, considering my ST doesn't actually weld to BB:

DT to BB, both sides. ST to DT both sides. DT to HT both sides. TT to HT both sides. TT to ST both sides. 
Should I go back and tack at each quadrant of each intersection from here?

3. Weld front triangle

So that's my plans for now- My goal is to be able to do my first test ride by mid-june!


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## A. Spence (Sep 25, 2009)

thedudeman said:


> 1. Learn to silver braze so I can do my bottle cage mounts. I did the holes in my DT and ST and I read on Anvil's framebuilding guide to braze before welding. Do you guys recommend doing cable guides before welding, as well? Is my hardware store product here going to cut it? (got advice from a plumber friend to try the local welding shop, but they weren't open so I grabbed this):
> View attachment 880539
> oh and I have an oxy acetylene setup I can use for this.


You need silver brazing wire/rod. What you've got there is silver solder, which isn't going to have the tensile strength necessary to make a strong enough bond.

Get some Harris Safety Silv 56 from Henry James, or some of the Cycle Designs equivalent.

Alistair


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## G-reg (Jan 12, 2004)

I'll second a few points here.

You really should acquire some proper 56% and appropriate Flux from Henry James s or Cycle Design. 

And it's an extremely good idea (x eleventeen) to do as much drilling/brazing prior to final mitering for the main tubes.


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## thedudeman (Nov 10, 2006)

Just ordered the HJ Harris 56% silver and the flux. Kind of regretting wedding these bottle mounts since its brought things to a crawl. Anyway, I'm committed now! 

A little concerned that I have already mitered my main tubes and have not added cage bosses. But holes are already drilled. Luckily I'll have a chance to tweak my fit up if need be. 

One more question: cable guide braze ons- should I do those befor tacking tubes together as well? I'm assuming ill use the same silver braze technique for these zip tie style cable guides?

Thanks again!


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## thedudeman (Nov 10, 2006)

*Silver Braze practice!*

Alright, back at it! 56% silver braze and silver flux arrived from henry james yesterday. I slathered it on like I saw in the "From Steel" video, and since I didn't have a respirator, I did it outside between rainstorms. I don't have a lot to practice with, but I used one of the actual bottle cage bosses that I'll be using on the frame with a 1/4" hole in a piece of 1-3/8" scrap, .9 thick. 
I got going and expected to see the flux liquefy, or a big cloud of smoke like the "From Steel" video, but instead, the flux started turning black. So figuring things were overheating, I jabbed the silver into the joint, and it wetted all the way around (and then some) so I stopped. 
I'm assuming I overheated it, but wanted to see what you guys think. I don't really understand how the silver goes into the joint instead of just everywhere, but for the most part it seemed to work.







After a lot of cleaning and wire brushing and sanding, I got it to what it looks like below. There are a couple parts that make a perfect little fillet, but others where the silver ran down the tube, and where the fillet is porous. I'm guessing this is from overheating too? Maybe I was too lazy and used a small cutting tip on the oxy-acetylene torch. I just figured I could control the heat, but I think things happened too quickly.


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## thedudeman (Nov 10, 2006)

OH yeah, should I use a reducing flame here? I just went with a neutral flame because that's what I'm used too...


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## TrailMaker (Sep 16, 2007)

Hey;

Think soldering, not brazing. Solder and silver go fast and easy, and at lower temps with a softer flame. Brass needs to be pushed and flowed.


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## dr.welby (Jan 6, 2004)

Yes, too hot.

You're looking for a point between where the flux turns really smooth and shiny (like raw egg whites) and the tube starts to turn red. And I don't mean when the tube is red, that's too hot. You have to get to shiny, then coax it up to where the solder flows, but keep it out of the red zone.


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## A. Spence (Sep 25, 2009)

thedudeman said:


> So figuring things were overheating, I jabbed the silver into the joint, and it wetted all the way around (and then some) so I stopped.
> I'm assuming I overheated it, but wanted to see what you guys think. I don't really understand how the silver goes into the joint instead of just everywhere, but for the most part it seemed to work.


Yeah, you cooked it. Easy to do at first, especially with a short chunk of scrap which is much less of a heat sink than a full length of tubing.

In my opinion, brazing outside in the light of day increases the difficulty a bit too. In my shop I'll cut off a couple of the overheads so as to be able to read the color of the metal better. With silver, in a darkish room, you'll seed just a hint of dull red in the metal (if I flip up my no. 3 shades). Any more than that and it's too hot.

When starting out, don't be afraid to raise the temperature of the joint in steps. Apply some heat, then flick the torch away and take a good look at the condition of the flux and the color of the metal. Apply more heat, then have another look see. When you get more experience you'll be able to just get in there in one shot, flow the filler, done.

Lastly, I would try a softer, slightly carburizing flame. I use a Victor No. 1 tip with oxy-acet for bottle bosses but I know of other builders who use whatever tip is on the torch at the time.

Alistair.


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## thedudeman (Nov 10, 2006)

*Craaap!*

Ok back from vacation, got done with work and was psyched to hop right in there and get my bottle mounts brazed in my seat tube. Thought I had internalized all of the great tips from you guys without more practice :madman: and wound up overheating, with a much worse end product than my first try.

I polished up my tube with emery cloth and wiped it off with a dry paper towel. I didn't do anything to the bottle cage lugs. I also switched to a 00 oxy-acetylene tip. It seemed that the lug turned red rather quickly, and I was afraid to focus too much heat on the tube.









Lesson learned, but now (along with more practice) it's damage control time. It appears that I overheated my tube, is it dead? I sure hope not. Can I pop these out, clean up my mess and try again?

PS- is there a good way to just melt and wipe off my excess silver that's not even on the joint?

Thanks


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## BungedUP (Aug 18, 2003)

Dudeman - you can heat the excess, then use a wire brush to quickly scrub off the excess while it's still liquid. You can scrub away a lot of excess that way, then clean up with files, sanding, and Scotchbrite belts (if you have them and a Dynafile) or pads. 

It does look pretty cooked, but chances are you'll be ok. When you clean things up, check for cracks, then keep an eye on it over time. You can pull bottle mounts pretty easily, though you'll want to be a bit careful and not rip them out before they are ready. Put a screw in, warm up the boss quickly, but do not overheat it, then start pulling while just maintaining the temperature (don't continue increasing temperature or you'll roast things even more).


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## thedudeman (Nov 10, 2006)

Ok, do you recommend taking them out and starting over or just heating it up and adding more silver to where it needs it?


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## BungedUP (Aug 18, 2003)

Now that it's burned, it will be extremely challenging to try and add silver to where it appears to need it. Silver filler is very fussy about needing things to be clean, and it will be difficult to clean it properly without removing the boss that is currently in place. You can fiddle it by taking a small tipped steel tool, and manually agitating the silver against the steel while warming it, but that method really is reserved for trying to fix disasters. I'd pull it as carefully as you can, clean, inspect, then try again.


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## BungedUP (Aug 18, 2003)

When brazing stuff like that, don't move slowly. The tendency with gas torch work is to think that you can move it around slowly, and that it is just a big bludgeon of a tool. Instead, consider making your movements quick - add heat, pull it away, observe, and do this all within the span of a second. Of course, you need to know when to just let it sit there and warm things up, but when things get to the critical point, move that heat in and out as needed to maintain the correct temperature, and do it like a kung fu warrior! Not slow and plodding, but like flame karate chops. HIYA!


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## thedudeman (Nov 10, 2006)

Hi Peter,
Love the karate visuals! Already getting excited to get back in there and give it another go. I'm just glad this isn't built into the frame already!
I think I'll get another tube on the way just in case I can't recover this one. 

You mentioned that silver filler is fussy about cleanliness. Is the sanding/ simple green/ rinse acceptable? I think I under-did my cleaning this time by rushing and not even rinsing. 
Thanks again!


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## dr.welby (Jan 6, 2004)

I would soak off what you can, then go to town with the emery cloth and get all the flux off of there and see what you have. It's possible that you got enough flow around the bosses for them to work (at least long enough for a first bike).

You can pull off excess silver by using brake cable soaked in flux the same way as you'd use desoldering wick. But often when it has just flashed out over the surface emery cloth will take it off with less hassle.

If you clean off all the burnt flux you can reflux it and try to flow out what's already there or add a little if you missed a spot. The catch is that if there is any burnt flux in between the mating surfaces it's going to gum things up. Sometimes with a healthy application of flux you can float some of it out.

Next time, try heating up the tube in circles around the boss until the flux turns shiny. If you heat up the boss the heat doesn't flow out to the tube as well as heating the tube itself, and the boss overheats before the tube is a good temp and you end up with that burnt ring of flux on the face of the boss. Once the tube is where you want it, then a few flicks on the boss to get it up to temp too is all you need.


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## afwalker (Apr 26, 2012)

The humble water boss can be a real bear! Small flame and go slowly, and Dr. Welby's tips to avoid overheating the boss will help. Now wait until you try and do a stainless steel boss! I hate those things!!! Ever so easy to overheat
andy walker


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## thedudeman (Nov 10, 2006)

*Bottle Bosses!*

Peter, Allistair, Andy, Dr. Welby and TrailMaker,

Thank you all for the advice! I moved much more quickly and heated the tubing first as a result. I THINK (and hope) I improved today from the suggestions. A few other mistakes I made yesterday were: 
1. Too hot of a flame (cranked down the acetylene)
2. Mistakenly went to a 00 when I was using a 000 tip to start with, which made things hotter (and worse) for my second try. 
3. Got lazy about cleaning by not rinsing. No idea why I did this on one of the most permanent things I've done to my frame so far, but I learned my lesson!

I think today went pretty well. I cleaned up my ST disaster, checked for cracks, cleaned it again, then tried again. Went much better, so I went for it on my DT bosses:








My question for the day: Should I attach my cable guides before tacking the front triangle? Thanks again!!!

-Scott


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## Eric Malcolm (Dec 18, 2011)

Scott

I would leave the cable guides to later. On the first frame it is enough to focus on getting the mitres at both ends correct. Putting on guides makes this task harder to do as you are locked into keeping the mitres precise (Assuming you have not mitred yet). If you have already settled on a precise mitre, then your call. Some builders will do guides before, others do it after, its a matter of personal preference.

The final brazing of the bosses look good by the way.

Eric


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## BungedUP (Aug 18, 2003)

Scott - NIIIIICE!!! Looks great - big improvement. Nice and smooth, not burned, very little excess. I'd hire you!

I'm with Eric - do the cable guides afterwards.


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## thedudeman (Nov 10, 2006)

BungedUP said:


> Scott - NIIIIICE!!! Looks great - big improvement. Nice and smooth, not burned, very little excess. I'd hire you!
> 
> I'm with Eric - do the cable guides afterwards.


Wow! Thanks! Excited to tack up the frame next, and I'll wait on the cable guides- I did one practice guide today and it looks nice, if a little hot. Got the idea to file to match the tube from the other thread on the topic.


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## afwalker (Apr 26, 2012)

woohoo! that's better heat control. Sorry if I wasn't clearer, I meant get it up to heat slowly, but with fast karate chop moves Watch the flux grasshopper!
cheers
andy


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## TrailMaker (Sep 16, 2007)

There ya go!

I'm no gasser, but they look pretty good to me. I just TID'd my guides on, and used nutserts for my bottle bosses. Quick and expedient. Obviously, it is easier to put the bosses on first, but I would also do them afterwards. I didn't even put them on my first frame. I figured I was busy enough without those details. It wasn't a big deal when I actually did it, of course.

I've done just enough gas work in the distant past to offer one bit of advice; for general brazing, use a tip that allows you to get the heat you need with at least a moderately soft flame. Not only will it be easier to control, but the softer velvety hiss will add immeasurably to the Zen aspects of the experience.


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## thedudeman (Nov 10, 2006)

*weld sequence*

I've been doing some searching for weld sequence on the front triangle, and haven't found a whole lot. One thing I would like to do was what this guy did:
My frame #1

He welded the top of the DT first so there was room to easily complete the weld before tacking in the TT. Is there any reason not to do this? Seemed like a good trick, but I don't know how much things will warp.

Lastly, what makes a good tack for this kind of welding? I know keeping heat down is good, but I was wondering: do I want an actual weld-like tack, or one that is very small? If that makes sense. Walt mentioned in the thread above about tacks possibly causing stress cracks?

Also I read about a "lay rod" technique mention by Peter (bungedup) in another thread showing his awesome work. I've been dabbing along with pulsing- is the lay rod thing what it sounds like? Just kind of "running over" the rod as you weld?


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## BungedUP (Aug 18, 2003)

There are a lot of ways to do it, and it doesn't really matter too much, in my opinion. Sometimes, a certain sequence is necessitated by unusual circumstances - I have encountered tandems that will only go together a certain way - these are usually ones with laterals, and a broken/disjointed top tube. They require a specific, well thought out approach to complete. Standard diamond frame single bikes are a lot easier, and I've never encountered one that required much trickery in order to put together.

I'm not sure how you are doing your fixturing, but if I were to make a suggestion 
(and it is JUST a suggestion), it would be to just tack the entirety of the frame (including rear triangle), then weld it once free of the fixture. I would suggest not trying to pull the frame in and out of the fixture a bunch of times, for different parts of the frame, unless it is necessary to do so (such as it didn't tack up well, and you need to tear the rear triangle off to fix wheel alignment, or something like that).

I personally assemble and tack the front triangle, welding around the back of the seat tube so I don't have to fight that battle with the chainstays in place, then tack the chainstays, then the seatstays. Then I pull it out, and weld the frame, checking basic frame / wheel alignment before welding, and again after. I check alignment before welding to catch any grevious errors, such as those caused by dropouts not seated in the dummy axle all the way, bad fitting dropouts, etc.

I wouldn't worry about coming up with any particular "type" of special tack weld- you can do all sorts of things. Just as a place to start, you could just put a 3 to 7ish puddle weld along the centerline of each tube. You could put small single puddle tacks rolled 20 degrees or so from the centerlines. Some people make really small tacks. I generally don't, even when it is possible to do so. Most of the time, I'll make little centerline welds where I can get to them, and whatever blob I can lay down in areas that I can't. It's worked well for me, and after thousands of frames, I'm not aware of a single one having troubles after the fact due to how it was tacked. Other people get really specific about it, and they may have arguments for doing it a particular way, and I can understand that.

Lay rod/wire is much like what you describe. There aren't many people who make videos that I recommend, but I DO recommend Jodi from Welding Tips and Tricks. He consistently gives correct information and technique. Here's a short video describing and showing the difference:






I'd just continue to practice, and do whatever feels right to you. I like laywire, but I also do a lot of "dip" filler addition. It feels right for certain types of work to me such as below:









Not my best example, but that's beside the point - use what ever technique YOU feel comfortable with, and think is right. There's a lot of ways to skin the cat.


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## compositepro (Jun 21, 2007)

BungedUP said:


> There are a lot of ways to do it, and it doesn't really matter too much, in my opinion. Sometimes, a certain sequence is necessitated by unusual circumstances - I have encountered tandems that will only go together a certain way - these are usually ones with laterals, and a broken/disjointed top tube. They require a specific, well thought out approach to complete. Standard diamond frame single bikes are a lot easier, and I've never encountered one that required much trickery in order to put together.
> 
> I'm not sure how you are doing your fixturing, but if I were to make a suggestion
> (and it is JUST a suggestion), it would be to just tack the entirety of the frame (including rear triangle), then weld it once free of the fixture. I would suggest not trying to pull the frame in and out of the fixture a bunch of times, for different parts of the frame, unless it is necessary to do so (such as it didn't tack up well, and you need to tear the rear triangle off to fix wheel alignment, or something like that).
> ...


Are you saying you use lay wire for most of your welding? and this is with pulse?


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## BungedUP (Aug 18, 2003)

Compositepro - The photo is not with laywire, but with the traditional dabbing method, timed with the pulse. I do however perform a lot of work with laywire technique. I was trying to help Scott understand the process via the video link, but also suggest that since he has been practicing, he should do what he feels is working the best for him, and to have confidence in that.


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## thedudeman (Nov 10, 2006)

BungedUP said:


> There are a lot of ways to do it, and it doesn't really matter too much, in my opinion. Sometimes, a certain sequence is necessitated by unusual circumstances - I have encountered tandems that will only go together a certain way - these are usually ones with laterals, and a broken/disjointed top tube. They require a specific, well thought out approach to complete. Standard diamond frame single bikes are a lot easier, and I've never encountered one that required much trickery in order to put together.
> 
> I'm not sure how you are doing your fixturing, but if I were to make a suggestion
> (and it is JUST a suggestion), it would be to just tack the entirety of the frame (including rear triangle), then weld it once free of the fixture. I would suggest not trying to pull the frame in and out of the fixture a bunch of times, for different parts of the frame, unless it is necessary to do so (such as it didn't tack up well, and you need to tear the rear triangle off to fix wheel alignment, or something like that).
> ...


Peter,
Thanks for the advice! I apologize if I am asking too many questions, please let me know if that's the case. I did some more TIG yesterday, and it was great that I could make it all the way around a tube with a pretty decent looking weld _while _trying different techniques.

Somehow I started pulsing 2-3 times per second, which still made an ok looking weld, but too hot and tons of ripples. Thought back on what you said about stab the pedal, then mooooove, and got a couple of awesome "stack of dimes" spots.

Good to hear I can do whatever works as far as order for tacking. Also glad to hear that I can just take it out of the jig for final welding (which is what I was hoping to do).

Love the welding tips and tricks videos! Thanks for that one- Jody is a kick!

Wife is yelling at me to leave! uh oh!!! Thanks again

Scott


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## BungedUP (Aug 18, 2003)

Heck no you aren't asking too many questions!

You should have confidence to choose your own methods, however, as you are doing a good job of preparing, and spending time practicing and all that.


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## thedudeman (Nov 10, 2006)

*Progress!*

So I got the front triangle welded together!
Overall I'm pretty happy with the welds. Got a couple small tungsten inclusions that I ground out and welded back over, but other than that no real trouble.

Scariest parts was the bottom of the HT/DT junction. I was getting into the thick part of the headtube, and was struggling to get enough heat and wire fed in there even at 90 amps. The other scary spot was the acute angle between the DT and ST. I've never stuck the tungsten out that far, and as much as I had to step on it I was afraid the arc would wander and burn a hole in the side of a tube... That one also seemed like it took a lot of filler! Anyway, super excited to continue, got some cranks on the way to start figuring out the rear end.

Thanks again everyone for the help


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## TrailMaker (Sep 16, 2007)

Ha!

Now for the fun part!

:devil:


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## thedudeman (Nov 10, 2006)

TrailMaker said:


> Ha!
> 
> Now for the fun part!
> 
> :devil:


I've got spare seatstays for the occasion- hopefully enough!


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## afwalker (Apr 26, 2012)

pretty darn good
did you do any heat sinks like that HF tailpipe or make your own?
Doesn't look like the HAZ is bad at all, so good job!
Very satisfying rapid improvement on the welding.
cheers
andy walker


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## thedudeman (Nov 10, 2006)

afwalker said:


> pretty darn good
> did you do any heat sinks like that HF tailpipe or make your own?
> Doesn't look like the HAZ is bad at all, so good job!
> Very satisfying rapid improvement on the welding.
> ...


Andy- thanks! 

I did not get a chance to make a heat sink. It is on my list of stuff to make (planning on taking a look at the tailpipe one at HF next time I get down there). I just switched regions where I was welding frequently to deal with it as best as I could.

Scott


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## thedudeman (Nov 10, 2006)

*CS progress*

Since no CS fixture yet, I decided to try using my mitering jig that I used for the main tubes. Picked up the angle spit out by my drawing:







I tried a few ideas for getting a close representation of the Nova CS, but the best I came up with was basically tracing it to graph paper, then plotting it into the CAD program using cartesian coordinates. it was slow, but worked pretty well.

Notching seemed to go well, and the results seem ok so far. One issue was the excessive stickout of the stay while cutting, which caused some height issues, but I think it's not a big deal (yet):








Next, I decided I need some long overdue practice capping, notching and welding thin CS material to thick dropouts. Here's my cap and fit, which Zoey my golden retreiver was extremely helpful with:








I cranked up the amperage to 125 or so and went for it. Some looks good, but even while focusing heat at the dropout, I managed to melt away my little cap on the stay:








Should the weld be bigger/hotter overall when welding thick to thin, or should I maintain the same size bead as if welding on thin material? I'm going to try colder on my next practice joint, but just curious if a colder bead will attach itself sufficiently to the thicker plate.
Ps- my practice plate is almost 6mm, and my real dropouts are about 5mm I think...


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## TrailMaker (Sep 16, 2007)

Hey;

Hot enough to get a puddle in the plate is all you need. Lay your weld into the plate and wick it over to the tube. That way it won't just melt the tube away from where you want the bead to be.


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## afwalker (Apr 26, 2012)

Question on the cap, they're not silver brazed before you tig no?
That'd mess up the weld, so I'm told.
I'm guessing maybe no, since the higher heat of tig would melt the silver, 6000 to 1500 deg.
cheers 
andy walker


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## thedudeman (Nov 10, 2006)

Hi Andy- the cap was notched out with a hacksaw, then TIG with no filler, then filed into a decent looking shape. About to notch my actual stays now- wish me luck! 

And trail maker- thanks for the tip- if that's the case, I think I feel pretty comfortable welding them on my frame.


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## thedudeman (Nov 10, 2006)

*Tonight's CS droput progress*

After my practice chainstay joint, I decided to go for it on a real stay. It came out pretty good, accept my coping cut to the BB and the dropout slot aren't perfectly perpendicular. I was thinking I'd tack the dropout, then twist it just a hair until the fit is better. haven't decided if I'm going to grind the weld on the caps flush, or just leave em.









Part of the reason it took so long is because it was by hand, and it was all hacksaw and file work. Also I didn't have any flat chromolly, so I just cut a tube in half and flattened it to make my little cap.


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## afwalker (Apr 26, 2012)

Leave em! You did a very nice job on that fusion weld!
Of course you can smooth them out and it would be nice too,
But you did well on the heat control on that thin tubing!
Your notch looks like it should be just great, heat on the dropout, good amount of filler to keep the thin stay from overheating, enjoy
cheers
andy walker


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## thedudeman (Nov 10, 2006)

Andy-

Thanks! It was fun, but getting it to fit was a bit scary! Hopefully I can get the other one done today 

Scott


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## ktm520 (Apr 21, 2004)

You can also weld the caps on last.


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## thedudeman (Nov 10, 2006)

*rear end mock up*

So I'm starting to experience the "fun" of the rear end... Everything was going great, until I tried to twist a chainstay and put a dent in it (even though I used wood to stop that from happening). Wound up tacking the drive side CS in place and twisting from the dropout to get it vertical, which worked. Wheel spins, cranks spin- CHECK!









My main problem I'm going to try to solve for the next hour is that the wheel is too close to the stay on the drive side... Kind of dreading this to be honest. Hopefully it works out- I don't want a frame buzz on every hard corner I take.


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## thedudeman (Nov 10, 2006)

*good news*








So I welded my drive side CS on more securely and went to town with a crescent wrench at the dropout. It seems like these dropouts kind of saved me. I can see where having a fixture for the cutting the rear end would have been nice! I don't think I was too far out of alignment, as much as getting minor tweaks too far in either direction until it finally worked out. Once the dropout sit nice on the dummy axle, I re-mocked up with the wheel and cranks and it appears that the wheel is nice and centered! Thank goodness! 








Next is to tack, align, then weld both stays on. After that, it's figure out how the heck I'm going to bend my seat stays. In the mean time, I need to track down a 44mm HT reamer.


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## TrailMaker (Sep 16, 2007)

Fixtures and jigs are a wonderful thing!

But don't worry, this fight is learning you A LOT!


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## slow (Jun 25, 2009)

The Dudeman, thanks for sharing. It's real fun to follow along.


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## thedudeman (Nov 10, 2006)

*seatstays round I*

So I have learned a ton from jay_nwtr's thread about his first build. It was my go-to for my seatstay bends, and it was extremely helpful, so "thanks!" if you're still on this forum.

I basically copied his final setup that seemed to work for him, and through some other reading I settled on an 11" radius. I made the form out of the big chunk of maple I still have left after making my tubing blocks. 







As soon as I got it done, I just went for it and to my surprise, it worked! No kinks, and the bend is fairly smooth. No buckling either! I bent to 16 degrees, which appears to be enough, but we'll see after I create a quick CAD drawing of the setup!









I'm actually pretty happy with these, but I'm also curious about what will happen if I move the feet closer together, and also how far it will bend before kinking. Also kind of s-bend curious, but I'm going to try fitting these guys up first before I try anything fancy.

Hopefully this aligns with my previous "up next" section, but I think I'm going to get these to fit, then figure out how to align my front triangle. My Seat tube is roughly 1/8" off to the right at the top, according to the anvil jig. I'm thinking I'll build something bomber to bolt the BB to, and just bend it by hand? Haven't researched it yet, but I just noticed that issue tonight.


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## thedudeman (Nov 10, 2006)

slow said:


> The Dudeman, thanks for sharing. It's real fun to follow along.


Heck yeah! Here's to hoping the end isn't "exciting"!


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## TrailMaker (Sep 16, 2007)

Ha!

Nice bending. That worked out well. It always surprises me that this tubing bends that well using those methods. I never assumed it EVER would. .125 off on the ST? That's kind of a lot, eh? Have to do something about that! I didn't have anywhere near that kind of deviation on mine. I think it was about .0115". I used my BB mandrels, bolted it to my mill bed, and gave it a yank. A "controlled" yank, of course.


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## bikecycology (Apr 26, 2010)

nice work


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## Eric Malcolm (Dec 18, 2011)

Just be aware when pulling the seat tube over that you are also attached to the head tube via the top tube, so you need to be clear that the head tube does not move as well.
So check all variables of alignment....this is challenging I know, but it can be done.

Lots of learning for you, through this frame you will be quite proficient as you have had a few obstacles to overcome.

Eric


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## thedudeman (Nov 10, 2006)

Trail maker- it suprised me that it worked in the bending as well! The main thing I can think is that the 5/8" slot I cut is extra dep so the side walls of the wood keep it from buckling, but it appears others (meriwether?) have has success with a simple v-groove in wood. 

Eric- thanks for the tip. This is one thing I am a little concerned about. I read a document from anvil about "witch wanding"... Since I don't have a bb arbor, but I do have a torch, could this be a better option for pulling my st back? 
Hopefully there isn't a whole lot of feedback to my HT... One step at a time!!
Thanks you guys!

Scott


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## Eric Malcolm (Dec 18, 2011)

Scott.

Not sure how to answer the 'witch wanding' in this instance. I have done this on forks and chainstays, but 'cold setting' is what I have done on a front triangle.

Hopefully someone here who has used heat could help.

Eric


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## BungedUP (Aug 18, 2003)

Scott,

Regarding the tire being too close to one of the chainstays:

Step 1: Have you aligned the stays with a frame alignment type gauge? You can make one yourself. It is simply a rectangular tube that sits on the headtube and seat tube, and is either bent in a z shape, or cut and welded, with an adjustable bolt on the end. You can use this to gauge the outside of the dropout on one side, then the outside of the dropout on the opposite chainstay. Center your stays, then see if the asymmetry is still there. If it is then proceed to step 2:

Step 2: with the tire removed from the wheel, and the wheel properly trued, sight down the wheel and see if the rim is in line with the seat tube, with the seat tube being inline with the head tube (square the front triangle first). If the rim is off center, is it off center and in agreement with the misalignment of the chainstay? If so, then you can file the dropout to make the wheel sit square.

Step 3: Assuming that the the conditions of step 1 and step 2 are met, you can file the dropout with a round file so that the wheel alignment drifts into the correct position. If the wheel is off, it is better for it to be off in the direction of the drive side, as you then file the drive side *forward*, which is the same direction that the wheel is pulled when chain tension is put on it (effectively pulling the wheel into the slot that you've extended). Needing to file the non-drive side dropout is worse, as then you need to file forward, but the wheel will want to slip back when chain tension is put on it. DO NOT FILE DROPOUTS UNTIL SEATSTAYS ARE ATTACHED! Cardinal rule. Don't violate it. 

Wheel alignment is tricky - I find in some ways that tacking the entire frame together, including seat stays and chainstays, is easier than trying to pull it in and out of the fixture multiple times. When you tack it together and check in your fixture that the chainstays and seatstays are balanced, there is structure that helps maintain the proper alignment. When the chainstays are welded up without the seatstays in place, there is no triangulation to keep each tube member in check. Dropouts can twist, chainstays can move up and down, etc.

Regarding seat tube alignment, .125" is off more than necessary. You can clamp the BB shell in the vise and pull on the seat tube, or you can use heat (I think you are using witch wanding to describe that). To move the seat tube, you will want to heat on the side you want the tube to pull, with slight pressure in that direction as well. If you want the top of the seat tube to move to the drive side, heat the drive side of the seat tube near the BB (or in your case near the DT, but don't heat the DT if possible, as that will alter alignment as well). You want to heat until the tube just starts to show dull color (DULL!). Apply pressure during the heating, or at least the end of the heating cycle, maybe starting with about 10-15lbs of force. Hold that steady for at least 20 seconds. Then wait at least 3 minutes to cool. You actually get 3 movement cycles from the heating. It will grow away from where you heat it (and that's when you need pressure holding it to counter that), then it will start to contract, swinging back to where it started, then beyond, as the pressure you applied caused the tubing to swell on that side, thickening it and shortening it. The tube will continue to move back beyond where you started, go for a little ways, and then it will pause. Strangely, it will then AGAIN start to move, for another several seconds (maybe 30?). Then it will be done moving.


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## thedudeman (Nov 10, 2006)

BungedUP said:


> Scott,
> 
> Regarding the tire being too close to one of the chainstays:
> 
> ...


Peter- 
Wow! Thank you for all of the specific details- I'll be studying this post for a while and will not violate the dropout rule 

Re:witch wanding- I read about it in this document (and the name sounded cool):

http://www.anvilbikes.com/wp-content/uploads/2014/02/Anvil_how-to-build.pdf

This is also where I got the idea to do CS only first, but I see (and have now experienced)your point about things moving up down sideways and all over the place without being triangulated.

Looking forward to trying out your suggestions!

Scott


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## todwil (Feb 1, 2007)

Would it be better to put frame back into the jig and capture the HT also before cold setting the ST so you dont pull it out of alignment while fixing the ST alignment?


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## thedudeman (Nov 10, 2006)

todwil said:


> Would it be better to put frame back into the jig and capture the HT also before cold setting the ST so you dont pull it out of alignment while fixing the ST alignment?


That would be nice... I pulled on the ST lightly and the jig deflected, so I decided no-go on that one.


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## BungedUP (Aug 18, 2003)

I think that some people might suggest pulling the frame out and checking wheel alignment before installing the seat stays because they don't trust their fixture, or they don't trust there process. This is completely understandable when you don't make tons of bikes, BUT it's a little like checking on a souffle in the oven. Each time you check it, there's a chance for it to fall. It's not exactly the same, but that's the closest analogy I could come up with.

If you install your dropouts properly, reduce all gaps between joints to the smallest amount you can, check the position of the tubes while in the fixture, and are working with a reasonably square fixture, it is simpler and thus offers less room for errors to creep in, to leave the frame in the fixture from start to finish (until it's ready to weld).

I know that its hard to resist doing otherwise though, and I'm not judging those with a different process. I'm just describing the way I think about fixturing/tacking. 

-Peter


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## Eric Malcolm (Dec 18, 2011)

Just a thought that has not been mentioned so far, have you checked your frame on a surface plate? Might pay to do this if possible, your frame may or may not be as bad as you see as at present. I read the problem as where the seat tube has come off the theoretical BB shell (actually the D/T) at an angle, and if left like this, your crankset when fitted, will not be in plane with the rest of the frame. Do I understand this correctly? If you could more clearly establish which frame item is out would be very helpful, as looking again at the frame with some of that meaty tubing, cold setting could be a challenge too far.

If I am 'off' today just ignore me.....

Eric


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## thedudeman (Nov 10, 2006)

Eric Malcolm said:


> Just a thought that has not been mentioned so far, have you checked your frame on a surface plate? Might pay to do this if possible, your frame may or may not be as bad as you see as at present. I read the problem as where the seat tube has come off the theoretical BB shell (actually the D/T) at an angle, and if left like this, your crankset when fitted, will not be in plane with the rest of the frame. Do I understand this correctly? If you could more clearly establish which frame item is out would be very helpful, as looking again at the frame with some of that meaty tubing, cold setting could be a challenge too far.
> 
> If I am 'off' today just ignore me.....
> 
> Eric


Hi Eric,
I think what has happened (as far as I can tell from the fixture) is that the BB and HT are perpendicular to each other, but the ST is off at a bit of an angle toward the inside of the fixture. It has always been a bit funky, since the ST offset doesn't allow the cone to sit perfectly in the tube like a normal front triangle, but if I clamp the cone just above the ST hole (maybe ever so slightly contacting one edge), you can see that it's off. 







I do not have a surface plate, but maybe I can cobble something together for next build??
Scott


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## thedudeman (Nov 10, 2006)

*Aligning stuff!*

Alrighty, so tonight I started going down the list of some of Peter's suggestions. First thing I did was fab up a frame alignment gauge, which was kind of a fun break for me. Curious that I seemed to have a harder time welding mild steel that is at least twice as thick as the chromo I've been doing, but I suppose that's a practice thing since it's a different setup. Anyway, I thought it would be fun to silver braze a nut in place instead of welding it, since now I can! Pretty happy with the results there, but the thin part of the metal overheated and silver went all over on the thin end. 








Next I tried to cold-set the frame using a milling vice and yanking on the thing. Seemed like it didn't want to budge, and sure enough, it didn't after four separate tries. So I went for the more drastic measure: heat. Tried to keep the heat off of my DT and lower bottle boss, and I think I was mostly successful. It was a bit scary taking the torch to the frame, but I took my time and turned the lights off so I could see the dull red Peter mentioned. Now it sits nicely with the fixture! Super happy that is fixed!!!








Next I used my fancy new alignment gauge to check the frame. It was a bit out, so I gave the chainstays a bit of tweak, and now all is good there. Then I ran out of time 

Looking forward to the next steps and getting these seatstays finished up! Thanks again Peter and Trailmaker and Eric for the help! I wish I lived in the same town as you guys to buy you a bunch of beers!

Out of town again for the weekend, so I'll probably start back up Sunday night. Have a nice weekend everybody


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## Eric Malcolm (Dec 18, 2011)

Hey, that's really cool. I am really pleased this has worked for you. I thought cold setting might not be possible. Glad that the heat worked. I have not had to do that yet in aligning a frame, so good to know it works so well. How does the head tube align with the seat tube now? Hopefully its all good. Well done.

Eric


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## TrailMaker (Sep 16, 2007)

Adapt and overcome;

That's what manly men do. Cue that Cialis guitar.


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## thedudeman (Nov 10, 2006)

*Seatstay madness!*

After barely comprehending how I was going to use printed patterns to get hand-cut notches in phase with my bends, I gave up on that idea and went back to the fixture idea... sort of.

Since my handy 5/8" ball end router bit and maple bit did such a good job of holding the seatstays while bending, I figured why not make a fixed angle (between ss's) seatstay fixture out of maple? It will likely only work for this bike, but I'm ok with that. Variants of this fixed angle setup will be easy to make if I'm still to lazy too build a proper fixture for the next build. Did a test notch on the drill press using some extra tubing from Walt, and it did a passable job cutting. A little bit rougher cut than the setup I used on the lathe, but it did work. No tubes spinning free or crashes, which were my main concerns.









Next up is clean up these joints, and weld them to some thick material for practice. If that goes well, I'll notch my seat stays next. I think I'm simply going to tack weld a bar to the scrap portion of the dropout end to make things a bit more rigid while I cut them. After that, I'll start hand notching for my dropouts.


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## BungedUP (Aug 18, 2003)

While the setup was slightly different, at CM, we used one set block with an angle of ~ 14 degrees(?), IIRC for the majority of bikes. We varied the angle of the stays to the seat tube, but the angle of the seatstays relative to each other was fixed. It sometimes took a bit of massaging to get things to work right, but more often than not, the fixed block was about right. 

Nice work, Scott. I quite enjoy seeing your progress.


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## thedudeman (Nov 10, 2006)

*Looks like a bike!*

I don't have time to post much at the moment, but basically I capped, mitered and fit up my seatstays. Then I tack welded everything. Also found out that the dummy axle of the fixture is not parallel to the BB, which explains some of the "issues" I've seen on the rear end... learning a lot in the process!!

Here's a pic of cutting my seatstays:








...and the frame tacked up:








I can't wait to get this thing built up!

Next up is welding, SS bridge, maybe CS bridge?, then brazeons and HT reamed.


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## thedudeman (Nov 10, 2006)

*dropout weld trouble- not a disaster though...*



BungedUP said:


> While the setup was slightly different, at CM, we used one set block with an angle of ~ 14 degrees(?), IIRC for the majority of bikes. We varied the angle of the stays to the seat tube, but the angle of the seatstays relative to each other was fixed. It sometimes took a bit of massaging to get things to work right, but more often than not, the fixed block was about right.
> 
> Nice work, Scott. I quite enjoy seeing your progress.


That's cool about the fixed block- I was starting to get confused about all of the angles going into the junction, but just going for it helped. I'll definitely have more of an idea of what to do when I build a metal fixture.

I'm glad you enjoy seeing my progress since much of it is owed to you and others on this board 

I was chipping away at my SS bridge tonight, which was my first shot at the printed tube coping and it's working well so far. I keep re-working it, going for the perfect amount of tire clearance, which I'm basically just trying to match my ST clearance.

Anyway, I did some practice SS/ST joints, and I thought they came out good enough to go for it. 







I didn't have any metal as thick as my 1.6 ST to practice on, so welding the real thing is giving me a bit of trouble. I really have to put in lots of heat to get it wet into the ST, but keeping the puddle controlled on the thinner .8 SS has been challenging, but so far so good.

Where I am really having trouble is my SS/dropout joints. I cleaned everything just like I have been this whole time. But I'll establish my puddle on the plate dropout, transfer to the thin SS, and then it no longer wants to wet in on the dropout. I add more heat and it doesn't wet in, then when I stop I have a suity blackish residue. Would hitting this with a stainless brush help? I don't really want to hit with simple green then rinse because of all the water that will go in the frame... 
I had a bit of the same trouble on the other dropout, are these paragon things stainless? Does that have anything to do with it?
Anyway, I'm taking a break until tomorrow- maybe I'll be more fresh then!

PS- I bumped my amperage up to about 100 for these SS welds to thicker metal.


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## DWF (Jan 12, 2004)

Always put the seat stays on AFTER you're completed the joinery & checked/corrected alignment of the rest of the frame. Once the seat stays are on, any correction you make in the frame is communicated to the dropouts, doesn't matter if you're witch wanding or cold setting. Making corrections to the frame is very easy as long as the seat stays aren't on also. Read this doc for more info: http://www.anvilbikes.com/wp-content/uploads/2014/02/Anvil_how-to-build.pdf


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## thedudeman (Nov 10, 2006)

DWF said:


> Always put the seat stays on AFTER you're completed the joinery & checked/corrected alignment of the rest of the frame. Once the seat stays are on, any correction you make in the frame is communicated to the dropouts, doesn't matter if you're witch wanding or cold setting. Making corrections to the frame is very easy as long as the seat stays aren't on also. Read this doc for more info: http://www.anvilbikes.com/wp-content/uploads/2014/02/Anvil_how-to-build.pdf


Thanks! that's actually the doc I followed while building the rear of this bike. Everything is aligned now so seatstays were tacked and I'll do any if any final minor tweaks with a file at the dropouts if needed.

Anyone have any ideas why my dropouts resist wetting in while welding from a couple posts above?


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## BungedUP (Aug 18, 2003)

Scott - Can you post a picture of the dropouts/SS connection you are working on?

Thick to thin joints can be more challenging, and the base metal and fillers matter. Do you know what the base metal for the dropouts is?

Also, some basic things to check right now are:

1) do you have gas, or is your bottle running out?
2) clean gas lens?
3) sufficient gas coverage (suitable cup size, tungsten stick-out minimal)?

I understand that Scott is now beyond this, but regarding Don Ferris' (Anvil) approach to bicycle rear triangles:

I respect Don's work, and I also appreciate that there are different approaches to constructing bike frames. I do want to elaborate on my methodology, which differs in philosophy from both Don's, and probably many others as well. Part of my difference in philosophy probably comes from working in frame production, where you are trying to minimize the amount of time spent with each frame, and maximizing the accuracy so that people downstream are not having to fix your work. After reading Don's statement about alignment, it appears we are ALMOST in agreement, but not quite. Don's statement eludes to the need to weld everything but the seatstays first, _assuming that there will be a need to adjust alignment of the wheel_ (that's what I'm reading into his statement, anyway). My approach is the tack the entirety of the frame (including seat stays), then weld it. Don suggests not attaching those, but then welding the entirety of the frame, then putting the frame back in the fixture, then attaching the seatstays.

The more you fiddle with anything, the more chance there is for errors. I believe this is true for almost anything. The only reason to preemptively check alignment prior to attaching the seatstays is because you believe that either your equipment is faulty (fixturing), or your process is faulty (poor fitting joints, incorrect assembly into fixturing device, welding too much while in the fixture, etc.). As an example of things that can go wrong: when you pull the frame from the fixture, align it, then assemble it back again, you introduce the potential that your dropouts are not seated in the fixturing axle. If you weld, then align the frame, and it doesn't want to sit in the fixture in the same manner it did before (why would this be, if the frame is aligned*? I'll explain later  ), it can be difficult to place the dropouts back into the fixturing axle. And even if they ARE seated back into the fixturing axle, any adjustments that you made to them out of the frame fixture are now null and void. The position of the dropouts in the frame fixture is fixed - it cannot properly be in more than one plane. Welding the chainstays to the BB, when the chainstays have nothing to support their position at the dropout is asking for trouble! What is there to help keep the chainstays from moving up and down?

*Aligning the front triangle around the BB: If you align one side of the frame around the BB, it is very difficult to identify true flatness. The BB warps, and affects the seat tube and down tube differently. The seat tube will be properly "aligned" when it actually drops by some amount, that is symmetrical when flipping the frame from side to side. This assumes that warpage of the BB was the same from one side to the other, which is not necessarily true. Furthermore, this then will affect how the reference surface (side of BB) will interact with the frame fixture when you put it back in.

You can spend an ENORMOUS amount of time trying to puzzle you way through fixturing and tacking a frame by pulling it in and out of the fixture. On the other hand, if you know you are using a good process, have checked the likely places where things go wrong (bad fit, improperly seated parts), you can end up with a better aligned frame that took much less effort to construct. The complete frame itself helps to keep the various members in correct orientation for the very same reasons that the design of a bike frame is so strong for such a light structure.

Again, I understand that others have a different way of doing it, and I'm not saying do it MY way, not their way. I am just trying to present an argument for another strategy, and this strategy is based off of my experience from welding literally many, many thousands of frames, of varying types.


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## afwalker (Apr 26, 2012)

On your practice plate for the chainstays to dropout weld you said you used 125amps.
Is that what you used for the cs/dropout and it wetted out fine?
More power Scotty!
I'm curious about the sooty problem, I've had some of that recently, turned the gas up to even 30 cfh no help, cleaned the gas lens and it seems a bit better. I've just been wire brushing it off then acetone and going on. Curious to hear if that's just fine or a no-no.
Paragon has both steel and stainless drops in your style, just make sure you file/sand/emory the surface oxidation on both styles.
cheers
andy walker


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## DWF (Jan 12, 2004)

BungedUP said:


> Don's statement eludes to the need to weld everything but the seatstays first, _assuming that there will be a need to adjust alignment of the wheel_ (that's what I'm reading into his statement, anyway). My approach is the tack the entirety of the frame (including seat stays), then weld it. Don suggests not attaching those, but then welding the entirety of the frame, then putting the frame back in the fixture, then attaching the seat stays.


My statement alludes to the fact that the fixture's job is to locate the critical contact points of the frame within certain spatial and geometric relationships until the frame is tacked together. A fixture can't compensate for poor mitering, poor joinery process, poor heat management, etc. That's the builder's job and the fixture is not the builder.

The primary reason to build out and complete the frame prior to attaching the seat stays is simple: it affords the bespoke builder their last chance to easily correct any errors they may have made in any of the processes up to that point. Chainstays sucked in and need respacing? No problem as long as the seatstays aren't attached. You welded too many inches on one side of the bike and you have head tube twist? No problem as long as the seatstays aren't attached. Etc., etc.

Of course the goal is to have zero issues, but checking alignment is one of the final QA/QC checks a frame is subjected to post build. If you have an issue that needs correcting (and as I mention in the doc, the builder makes the call on what his acceptable tolerance is), then correcting it sans seatstays is straightforward, relatively easy, and much less stressful on the frame.



BungedUP said:


> The more you fiddle with anything, the more chance there is for errors. I believe this is true for almost anything. The only reason to preemptively check alignment prior to attaching the seatstays is because you believe that either your equipment is faulty (fixturing), or your process is faulty (poor fitting joints, incorrect assembly into fixturing device, welding too much while in the fixture, etc.). As an example of things that can go wrong: when you pull the frame from the fixture, align it, then assemble it back again, you introduce the potential that your dropouts are not seated in the fixturing axle. If you weld, then align the frame, and it doesn't want to sit in the fixture in the same manner it did before (why would this be, if the frame is aligned*? I'll explain later  ), it can be difficult to place the dropouts back into the fixturing axle. And even if they ARE seated back into the fixturing axle, any adjustments that you made to them out of the frame fixture are now null and void. The position of the dropouts in the frame fixture is fixed - it cannot properly be in more than one plane. Welding the chainstays to the BB, when the chainstays have nothing to support their position at the dropout is asking for trouble! What is there to help keep the chainstays from moving up and down?


I'm not sure what you mean by "what is there to help keep the chain stays from moving up & down? Are you talking about them rotating around the centerline of the BB, i.e., changing the drop dimension? The tacks or welds keep them from moving up and down. Ideally the dummy axle travels with the the frame and the dummy axle should be in place when the rear is being welded. The only time it's removed is to check rear spacing. Reseating the dummy axle, and ensuring it's reseated properly, is a very simple task.



BungedUP said:


> Aligning the front triangle around the BB: If you align one side of the frame around the BB, it is very difficult to identify true flatness. The BB warps, and affects the seat tube and down tube differently. The seat tube will be properly "aligned" when it actually drops by some amount, that is symmetrical when flipping the frame from side to side. This assumes that warpage of the BB was the same from one side to the other, which is not necessarily true. Furthermore, this then will affect how the reference surface (side of BB) will interact with the frame fixture when you put it back in.


I agree. The BB shell distorts with every weld pass, be it seat tube, down tube, or chain stays. This is why I encourage builder to not bother checking alignment during any of the intermediate stages if building in a documented fixture. In other words, builders often check alignment after attaching the seat tube to the BB shell, then again after the front harp. Facing & chasing the shell does not ensure flatness and new shells can't be trusted to have parallel faces. I've measure many brand new shells that were more than .010" out of parallel. The fixture doesn't care as long as the control surfaces rest/contact where they're supposed to on it. It's only when you start trying to force things on the fixture that problems occur.



BungedUP said:


> can spend an ENORMOUS amount of time trying to puzzle you way through fixturing and tacking a frame by pulling it in and out of the fixture. On the other hand, if you know you are using a good process, have checked the likely places where things go wrong (bad fit, improperly seated parts), you can end up with a better aligned frame that took much less effort to construct. The complete frame itself helps to keep the various members in correct orientation for the very same reasons that the design of a bike frame is so strong for such a light structure.
> 
> Again, I understand that others have a different way of doing it, and I'm not saying do it MY way, not their way. I am just trying to present an argument for another strategy, and this strategy is based off of my experience from welding literally many, many thousands of frames, of varying types.


Again, I agree. The difference here is that you have "many, many thousands of frames" behind you and you learned your skills in a shop environment; I would assume under the tutelage and mentorship of others who've already become competent builders. 99.9% of these folks don't have the luxury of that background and the internet is a poor substitute. Most of these folks are doing their best (I would hope) to learn in the bubble of their solitary efforts.

When I give seminars on building, I push that new builders first frames will be both better and worse than they imagine. You should have seen Walt's first frames!  Mistakes will be made, **** happens, they will never be the first or the last to dick something up in any particular way, and there are as many ways to build a frame as there are builders. The initial goal should be to have a safe & ridable frame and that comes long before the goal of producing a salable frame for those that wish to follow that path.

Basically, the steps on that doc are the distilled processes of what I've learned during my own career to date and from working with many of the established successful builders prospering today. As you say it's not the only way to build a bike&#8230;or as my Dad used to say, "there's more ways to skin a cat than stepping on his head and jerking on his tail.


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## DWF (Jan 12, 2004)

thedudeman said:


> Thanks! that's actually the doc I followed while building the rear of this bike. Everything is aligned now so seatstays were tacked and I'll do any if any final minor tweaks with a file at the dropouts if needed.
> 
> Anyone have any ideas why my dropouts resist wetting in while welding from a couple posts above?


1. Sooty residue is often the result of poor surface prep/cleaning but it can also be the result of having too much tungsten stick out; keeping too big of a gap between your tungsten and your work; holding the cup at too much angle to the work (which means the flow of the shield gas starts pulling/entraining air over the weld), and too little or too much flow on your shield gas. Make sure all your basic settings are correct first and try again on materials other than the bike you're building. If you're using any kind of lubricant when mitering, make sure it is completely removed before welding. Wiping the OD with acetone or denatured alcohol is not enough as oils can be captured in the pores of the parent material and then migrate out as it's heated up.

2. Never weld stainless dropouts without back purge or you'll get sugaring (black grainy surface on the stainless) and it's guaranteed to break. Know the materials you're using before you use them. 304 stainless is not very magnetic but 17-4 stainless is and Paragon has used both in their dropouts over the years so a magnet test may not tell you anything. IIRC, Paragon is only using 17-4 for their stainless dropouts now. Check your invoice for what they sent you. You can always do a spark test by taking a known piece of 4130 or bike tube and hit it on a grinder and then grab the dropout and hit it on the grinder someplace it won't show. You'll know right away if it's stainless or not. Stainless will spark yellow at the wheel and white at the end with big straight sparks. 4130 will spark mostly white with lots of volume and the tails won't be as long. Sparks are cool.


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## thedudeman (Nov 10, 2006)

DWF said:


> 1. Sooty residue is often the result of poor surface prep/cleaning but it can also be the result of having too much tungsten stick out; keeping too big of a gap between your tungsten and your work; holding the cup at too much angle to the work (which means the flow of the shield gas starts pulling/entraining air over the weld), and too little or too much flow on your shield gas. Make sure all your basic settings are correct first and try again on materials other than the bike you're building. If you're using any kind of lubricant when mitering, make sure it is completely removed before welding. Wiping the OD with acetone or denatured alcohol is not enough as oils can be captured in the pores of the parent material and then migrate out as it's heated up.
> 
> 2. Never weld stainless dropouts without back purge or you'll get sugaring (black grainy surface on the stainless) and it's guaranteed to break. Know the materials you're using before you use them. 304 stainless is not very magnetic but 17-4 stainless is and Paragon has used both in their dropouts over the years so a magnet test may not tell you anything. IIRC, Paragon is only using 17-4 for their stainless dropouts now. Check your invoice for what they sent you. You can always do a spark test by taking a known piece of 4130 or bike tube and hit it on a grinder and then grab the dropout and hit it on the grinder someplace it won't show. You'll know right away if it's stainless or not. Stainless will spark yellow at the wheel and white at the end with big straight sparks. 4130 will spark mostly white with lots of volume and the tails won't be as long. Sparks are cool.


Heh heh, sparks are cool.  this is the one I ordered, which says 4130 like I thought:
www.paragonmachineworks.com - DR2010SteelRearDiscBrakeDropout

I will try tracking down my invoice just to double-check. Someone here a while back mentioned that they were stainless, and I thought they were wrong. However, after the trouble I'm having it made me second guess myself...

I did practice welds on similar material, and have done the exact same cleaning process, although I could have messed that up, so I'll try cleaning again. My tungsten was pretty far out, coming from the SS/ST joints, so I'll check that. Thank you for the tips!


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## thedudeman (Nov 10, 2006)

afwalker said:


> On your practice plate for the chainstays to dropout weld you said you used 125amps.
> Is that what you used for the cs/dropout and it wetted out fine?
> More power Scotty!











that is a good point about using more heat on my practice joint and having it wet in without issue. I just thought it was a bit too hot then, but maybe that is the answer... I'll give it a shot! Thanks Andy!

Scotty


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## thedudeman (Nov 10, 2006)

*dropout wetting issues round 3*



BungedUP said:


> Scott - Can you post a picture of the dropouts/SS connection you are working on?
> 
> Thick to thin joints can be more challenging, and the base metal and fillers matter. Do you know what the base metal for the dropouts is?
> 
> ...


Hi Peter,
Here is a picture of the one that is giving me trouble (which is kind of embarrassing to be honest), then the identical one I haven't tried yet. Soot has been wiped off. On the second pic it looks like a gap, but that's actually just the cap filed flat.

















To answer the things you suggested to check:
1. Bottle is very big and has lots of gas.
2. I have never checked the gas lens for being clean. I suppose now is a good time!
3. My cup size is #6 off the top of my head with 1/16" tungsten. But the tungsten stick-out could be an issue, coming off of the SS/ST joint where I was trying to get closer in the acute angles.



BungedUP said:


> I understand that Scott is now beyond this, but regarding Don Ferris' (Anvil) approach to bicycle rear triangles:
> 
> I respect Don's work, and I also appreciate that there are different approaches to constructing bike frames...


I don't have much to add here, accept I am having a blast learning some of the ways professionals go about building cool stuff, while attempting to apply whatever I can!

Scott

PS- here's what I did tonight between working on lawnmowers hahaha


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## BungedUP (Aug 18, 2003)

Hi Scott,

I have a possible theory explaining the soot, which may or may not be the actual cause, in your case. 

When you cleaned your seatstay material, did you happen to see inside the tubing and clean it? Sometimes, tubing from certain sources carries a LOT of oil. True Temper comes to mind foremost. It's possible that even if you cleaned out an inch or two of the ends, that overnight, or however long it's been, oil from the inside of the tube has dripped down near your joint. That oil might cause the sooting that you see, even with a well cleaned exterior. I've seen TT tubing so oily, that even after trying to clean the ends very thoroughly, there is so much oil inside the tubes that it literally weeps out tacked joints left overnight.

The issue with the dropout plate not wanting to wet in - I think I have an idea of what's going on, but without going out to the shop and trying to replicate it, I can't quite figure out how to help you fix it (it's close to bed time). The root of the issue is heat control (that's so generic, it's sort of a dumb thing to even say). It would appear that you are attempting to penetrate really deep into the dropout plate, and using more filler in the attempt to do so. I need to either see you work, or try and replicate what is happening (I might be able to try and do that tomorrow after work), but my guess is that you need to bias the torch towards the seatstay (counter-intuitive), and use less filler. By canting the torch, you will be trying to penetrate less deep into the plate, and working more on managing the heat input of the seat stay material. It sounds counter to what you might be likely to want to do, and it IS counter, except on occasion. I'll try to experiment tomorrow, if I can remember though.


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## BungedUP (Aug 18, 2003)

DWF said:


> The primary reason to build out and complete the frame prior to attaching the seat stays is simple: it affords the bespoke builder their last chance to easily correct any errors they may have made in any of the processes up to that point. Chainstays sucked in and need respacing? No problem as long as the seatstays aren't attached. You welded too many inches on one side of the bike and you have head tube twist? No problem as long as the seatstays aren't attached. Etc., etc.
> 
> I'm not sure what you mean by "what is there to help keep the chain stays from moving up & down? Are you talking about them rotating around the centerline of the BB, i.e., changing the drop dimension? The tacks or welds keep them from moving up and down. Ideally the dummy axle travels with the the frame and the dummy axle should be in place when the rear is being welded. The only time it's removed is to check rear spacing. Reseating the dummy axle, and ensuring it's reseated properly, is a very simple task.
> 
> ...


This difference in procedure is interesting to me, and I'm not trying to be belligerent or difficult, just so you know. I like discussing some of these things, as it helps me to try and formulate the way I work or think. Please don't take this to mean I'm trying to say I am right and you are wrong, but I do want to make sure that what I'm saying is understood.

Chainstays welded without seatstays, can and do move up and down and left and right and all over the place. The amount of movement is related to the amount of gap in the joint. A good fitting joint doesn't move much. A bad fitting one moves more. When working with a frame that is largely of welded construction (as opposed to lugged or brazed), it's still relatively unlikely that you can adjust for a chainstay that has pulled in (changed length relative to it's mate). It's still an operation by which you need to either remove the dropout, or remove the chainstay, and that doesn't change whether the seatstays are attached or unattached (it's not an "easy" thing to fix, no matter what). You can't tip the wheel or align the frame in such a way to fix that.

What you gain by fixturing and tacking the frame in it's entirety, is a more rigid structure that helps hold itself in position while welding due to complete traingulation. Welding the chainstays without that triangulation leaves them without any support, and much less ability to counteract the effects of Mr. Shrink. Furthermore, if you do find you have to adjust something, the seatstay itself can act as an extra hand to keep the chainstay from just going where ever it wants to - it restricts it's position somewhat, in a beneficial way (again, I know this unfortunately from experience).

If the frame has minimal gaps, then the relative position of the members does not change much during welding. It constitutes so little change as to be considered negligible in most cases, when fitment is good, in my experience. That doesn't mean the frame will come out perfectly aligned when you are finished with welding (though it certainly can mean that). What it does mean is that when you return the front triangle to a good alignment, the rear triangle will seat the wheel in the proper alignment and square behind the seat tube when the rear triangle is aligned (wow, does that sentence sound weird).

Regarding my experience level: while it's true that I have had mentorship in metalworking in various forms since the early 90's, much of my philosophy has come from my own observations and dogged pursuit of figuring things out. One of the most valuable things I ever learned about building frames came from Hanz Scholz - if you didn't measure and write it down, it didn't happen. It's amazing the difference between what you think you thought you knew, and what the data tells you. I've found that kind of tactic is exceedingly rare in the professional frame building world, but it really shouldn't be.

I've watched people who've struggled to weld in a classroom setting, make enormous improvement (much more than what the class was able to do) due to the help of people in an internet forum. If someone is motivated, the internet can be an enormous boost to one's knowledge, which can translate to figuring out how to overcome incorrect procedures, bad habits, etc, plus offer encouragement to boot (which I found to be extremely rare in fabrication shops). These days, there are a lot of experienced people who enjoy sharing with others. Just look at this particular thread that Scott started - he has you, me, and several other knowledgeable people all offering him help! And not only that, he likes it! Can you imagine if we were all sitting around in person? That would probably be one of the most annoying things in human history, and he'd have told us to all go sit in the corner while he worked it out. As it is, we get to have the fun of helping someone who wants it, and he gets help from experienced people who want to give it to him. It's just a tremendous win-win for everyone involved.

I'm glad to read your posts about the issue, and to have a chance to express my own thoughts on the matter.

-Peter


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## BungedUP (Aug 18, 2003)

Oh! And I almost forgot:

You'd think that putting a dummy axle back into a frame is an easy thing to do, but we managed to cock it up quite often. It can be harder than you think, especially depending on the configuration of the axle and dropout. The worst ones were axles with what I call a "D" shape. These ostensibly offer the advantage of indexing, which is great for mitering stays, but can cause all kinds of issues when fixturing a frame. Trying to get the axle in the idealized correct position is hard enough the first time, let alone the second time. Most of these issues are really complexes with other issues - namely dropouts that don't exactly fit the "D" shape, pre-welded dropout/chainstay members that don't want to sit where you want them to, etc. I eventually started replacing our "d" shaped axles with round ended ones to alleviate some of the issues we were facing, and it improved the repeatability of wheel alignment on frames.

Typing it out, I feel like I'm just asking for someone to tell me the reason I couldn't do something as simple as put a dummy axle in place is because perhaps I'm just a consummate idiot! However, it really can be screwed up, even by relatively intelligent people. It actually took us quite awhile to realize where some of the troubles were coming from. We didn't know we were shifting the dropouts forward and back relative to each other as they rocked on the corner of the "D" shape. The round ones don't do that - the dropouts will more reliably sit concentric with the dummy axle.


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## Eric Malcolm (Dec 18, 2011)

I am surprised at the durability and length that this post has so far brought so many of a frame build's little issues all in one continuing dialogue - thankyou Scott. I for one am an old school lug frame builder, and find this forum a great place of learning and sharing, and the diverse experiences given by many is really appreciated. A day after stating that I had never 'witch wanded' a front triangle I found myself in a position where I had to do that very thing. I was passing a cable guide tube through a .5mm walled tube using silver only to find that the tube warped badly and sagged. I have never had that happen before, so the sag is now gone and I have a cunning plan to cover the warping. You never know when sharing that appears on this site can be very useful.

Scott, keep up with your updates as your journey covers many tricky aspects that subtly appear. It makes me feel young and a beginner again and its fun to feel like that.

Eric


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## TrailMaker (Sep 16, 2007)

Oh...

Stop gushing, you old goat. You're plenty young yet, and still full of beans! 

Here's another perspective. When I built my grand total of two bikes (so far), I just built them. Sure, I have 35 years of peripheral and fairly wide ranging experience with metal, and I just about wrote a book on bike building and machining with _The Professor_ (BungedUp) before I even got started (I copied and saved every e-mail!), but once I did start, I just built them. I checked my BB/ST for square after welding, and never measured them again. I mitered key/difficult nodes like the BB/ST, BB/CS, and ST/SS in fixtures on my mill, but all the rest were done by hand/eye with nothing but files, die grinder, and belt sander. I tacked it all together and welded them up in relative ignorance.

Everything fits, nothing needed filing or twisting, they never required any fiddling to get back into my fixture, and the eye ball says they are quite good enough. Granted, they are mountain bikes, and Fat at that, but they ride just as good as anything I've owned.

I took Walt's advice. "It's just a bike."


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## thedudeman (Nov 10, 2006)

*mini update*

Hi guys, this is mainly to save Peter some time experimenting with a similiar joint if he hasn't already (and thank you for thinking to go to all that trouble to help me!): I'm working on the frame right now, and cranked up the amperage to 125, changed out the diffuser and cup (same size, just fresh) re-cleaned the metal, and minimized tungsten stick-out...it worked a lot better. I even wetted in the crazy puddle I posted earlier so it looks better. However, got my most overheated part of my entire build under the SS.  I over cooked the meat in the area the size of a pea. but still!  It was just in one area, so I let it cool, repositioned and tried again and cleaned it up as best as possible. Full range of emotions so far tonight. hahahah

Will post more when done.


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## BungedUP (Aug 18, 2003)

Scott - I went out to the shop and tried to make a close approximation to what you are doing (thin sheet joined to plate at an angle of around 30 degrees) from little bits of scrap I had around.

I found that working with no pulser, that 100 amps was PLENTY of amperage to weld .250" bar stock to .035" tubing that I hammered into sheet. I started at 125, and while that worked, I was only 2/3 to 3/4 of the way into the pedal. At 100 amps, I still had room to feather the pedal in and out.

I varied the torch angle, and found that while I could get good results by making the angle fairly acute relative to the plate, (pointed more to the thinner sheet), it worked best with the torch 90 degrees to the sheet (not the bar stock). The technique of angling the torch relative to the thicker plate used to work well for me when welding 4130 plugs to stainless steel plate (dissimlar metals using 309L filler). The change in angle for that application helped me with bead consistency and resistance to cracking. This seemed to behave in a more traditional manner though.

I think that the amount of filler is critical though - I think that minimal filler to get to a filled joint, but not overfilled is key. Once the bead is over filled, I think you'll have trouble getting the bead to stay a consistent width once it has overfilled, which I _think_ was what resulted in the shape of your bead, which you were unhappy about.

John - excellent points! I was getting caught up in my alternate view of fixturing, which is really about minutia that doesn't matter to the majority of people. There really are LOTS of ways to do things that all end up with good results. I will say, your "eye-ball" is probably much like that of my former co-worker, Bob, which is to say about as good as a decent vernier caliper.


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## thedudeman (Nov 10, 2006)

BungedUP said:


> Scott - I went out to the shop and tried to make a close approximation to what you are doing (thin sheet joined to plate at an angle of around 30 degrees) from little bits of scrap I had around.
> 
> I found that working with no pulser, that 100 amps was PLENTY of amperage to weld .250" bar stock to .035" tubing that I hammered into sheet. I started at 125, and while that worked, I was only 2/3 to 3/4 of the way into the pedal. At 100 amps, I still had room to feather the pedal in and out.
> 
> ...


Peter, 
Wow that is really above and beyond- thank you for doing that! I see what you're saying about getting too much filler on there. Once that happened it was very difficult to continue the weld. I did try your suggestion of more angle towards the thinner metal and I think that helped as well. Probably near 90 like you just mentioned.

Man- these dropouts and .8 to 1.6 SS/ST joints (all thick to thin joints) were challenging! I feel like it knocked me down a couple levels as far as what I was getting on practice joints of the bigger, more concistent thickness materials. I think more practice joints of these types would have helped, and I'll do those before my next frame.

Good news is the frame is welded out save for the SS bridge which is only tacked in.

Eric- I'm glad you're enjoying watching me slowly get through this build! I was hoping by detailing all of my problems that it could help others, but I never expected this kind of response from everyone- very grateful- and back to Peter's point: I KNOW these tips, suggestions and encouragement have brought me a LONG way. It makes me a lot less cynical about the internet, experiencing first hand the positive impact a community like this can have on a guy like me /mushy rant.


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## afwalker (Apr 26, 2012)

Good job working it through, maybe I shouldn't have said warp speed
Now there's a lot to be said for just silver brazing those pesky SS bridges.
Warning: thin tube to thin tube with wonky angles ahead!!
I can't tell you how many times I've burned holes on those.
Use less amps, try some practice pieces thin to thin.
It may be one of the toughest welds
Totally different mindset, but you've handled everything else so far!
cheers
andy walker


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## TrailMaker (Sep 16, 2007)

Scott;

Regarding cleaning, I went through a very difficult period when it seemed that I simply could not get anything to weld without contamination, popping, fizzing, inclusions, etc. This was mostly with aluminum. I almost gave up on it completely. After replacing my torch that failed me... well... actually, I smashed it to bits in a fit of rage after yet another total failure... I gsve up being an individualist outlier and started to seek advice from real welders. The surprising consensus of these guys who do it for a living was to "screw the cleaning crap. Scrub it with a wire brush and weld it!" OK... they backed off that a tad, but they pointed out that ANYTHING you do to the surface is adding something to it. Chemical cleaning can be a contaminant in itself, and often times is just thinning out oils and such and moving them around. "Fine," they said. "Do your chemical cleaning, but the last thing to touch the part should be a stainless brush. Scrub it up REALLY good and get to it." I've not had to look back since taking that advice.

I think a really good welding test for you might be to try and FUSE thick to thin material with NO filler. Creating a puddle in the thick part and coaxing the thin to fuse into it. It's quite a game! Fusion welding definitely has its place and is quite proper for some applications, like welding two flanged stampings together, or when attaching edges of heavier stock. There are many times that I TIG pieces together, only using filler when I have a gap that is just a bit too wide to fuse, or doing fillets on inside joints. In the case of welding dissimilar thickness parts, it REALLY highlights the concepts of torch angle and heat placement. It is somewhat akin to gas welding where you are trying to "draw" the filler to where you want it.

For my own part, I never varied the amperage on my machine - a utilitarian Synchrowave 180SD - to do the DOs. I had no problems getting them welded at all. Perhaps it was my familiarity with playing torch angles and aiming the heat into the most advantageous spots. Or... perhaps it was just the dumb luck I frequently take advantage of!


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## thedudeman (Nov 10, 2006)

*head tube reaming*

So there are some good (and frightening) threads about reaming these 44mm PMW headtubes. I don't have a manual reamer/facer tool to start with, but through poking around I found that some do this operation on the lathe.

Here is my proposed plan, and I'm posting just to make sure it's somewhat sound:

1. Buy this reamer, since it includes the facing portion, and is in my budget:
Amazon.com : ICE TOOLZ Ice Toolz Headtube Reamer For Cane Creek Zs CANE CREEK ZS 44MM : Bike Hand Tools : Sports & Outdoors

2. Turn roundstock in my 3 jaw chuck until it's a good snug fit (without removing from chuck), make threads on the end and bolt the reamer to the chuck.

3. Use tailstock to center HT and use lots of cutting oil and a slow speed.

My main concern is having it catch, then flopping the entire frame over to the other side of the lathe then bending and destroying it. Any tips to avoid this? Or do you guys recommend just buying the cutter and using a shop manual reamer/facer? I'm a bit concerned about using a shop version, due to what I read about some of the park reamers going oversized for no good reason...


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## thedudeman (Nov 10, 2006)

Not a lot to update on the 44mm reamer issue, accept searched a lot of the shops where I would feel comfortable using their tools, and came up empty handed. Ordered the icetoolz reamer/facer, and mounted up the 4-jaw chuck to the lathe. Hopefully I can turn a good arbor and dial the whole shebang in with little runout. 

For some reason I was envisioning needing a live center from the tail stock, but I certainly don't want the frame spinning! Anyway, the outside of the Jacobs chuck has a nice taper that fits the 44mm headtube no problem, so I'm going to use that for support. 

I think I'll install my cable guides while I wait for this reamer to show up!


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## thedudeman (Nov 10, 2006)

Update- may add some pics later 

So the reamer showed up today. I machined an arbor that it presses onto, and used the face of the four jaw chuck for it to butt against. I used a huge 5/8-18 nut to cinch it all down. Then I used the dial indicator to get to where I had less than .001" runout on the back rim of the cutter. Was scared to smash my frame on the lathe under power, so I put it in neutral and used one hand to turn the chuck/ cutter, and the other to slowly feed the tail stock in. It turned into quite the workout! 

Anyway, first one (top cup) came out perfect- reamed, faced and a nice fit. Only complaint with the cutter is that it's a bit shallow for the cups, but I know how to solve that! 

Did the lower in the same way, went a bit faster, and the cup just dropped in! NOOOO!!! Before screaming, I tried the top cup- perfect fit in BOTH top and bottom. This is a brand new cane creek 40, 44mm headset. 

Grabbed the dial caliper, and I know they aren't the greatest, but showed .003" difference between top and bottom cup!

Anyone had this before? Pretty annoying since its a special order from my local shop. 
Not too excited about knurling or using loc-tite if I don't have to, so looks like I'm gonna be the annoying guy measuring headset cups at the bike shop!


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## BungedUP (Aug 18, 2003)

I've never, ever seen that, and I've installed a lot of headsets. I'm really surprised. Not even with super duper cheap OEM headsets that come in huge flats slathered in cosmoline have I seen something like that. I'll be curious to hear the explanation!


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## thedudeman (Nov 10, 2006)

I've been messing with bikes my whole life, and I haven't seen this either. 

The headset is bought as a top unit, and a bottom unit, which was new to me. But both CC 40, 1-1/8" flush mount top, 1.5 external cup lower.


Ill measure again, but the top one fitting well in both is what makes me think its real.


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## thedudeman (Nov 10, 2006)

I called Cane Creek today after re-measuring everything. I checked the ID of my headtube, and it's 1.732 (44mm), which is exactly at the top of Cane Creek's reccomended range. 

Lower Cane Creek HS cup OD is 1.731, upper HS cup OD is 1.734. .003" difference, which showed when I used a 1-2" mic as well. 

Cane Creek's explanation was that there is a tolerance range for these cups, but the guy I talked to didn't know what that is. So he suggested either measuring cups at a shop, or using loc-tite. 

I think I'm on the upper end of size, so I'll just have to do some searching. I suppose measuring could be off, putting me outside of the range that meshes with Cane Creek's tolerances.

Just suprised to see .003" difference in cup diameter. Seems like a lot to me.


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## thedudeman (Nov 10, 2006)

*Long overdue update!*

Sorry to anyone who was paying attention and especially those who have helped me so much for the huge delay. Learning how to do house projects like new hardwood floors, and actually riding bikes have taken priority for a while. TL;DR: scroll to the bottom for pics of where I'm at 

So here goes:

*Headset issues*: if you remember previously, I was having issues with my headset reaming. I thought I did a good job, but it appears that I am on the outside range of acceptable, perhaps even slightly oversize. The thing that got me though, was that within cane creek's headset cup tolerances (apparently plus or minus .003"), some of their cups fit, some didn't. 
So I did some hunting- had a top cup that fit, and a bottom one that didn't. Tried a second at a shop, didn't work. Shop owner was a jerk about it, so moved on. Ordered one online, pretty much resigned to using Loctite or knurling, but lucked out! The same 40 series cup I ordered fit perfectly. Dodged a bullet on that one!

My thought for the reason it happened is this: My setup on the lathe was solid, but the pressure against the cutter was feed by me, by hand. Although I was super careful, I figured any lack of pressure could allow the frame to drop out of alignment ever so slightly, then remove too much material as a result. Not catastrophic, but I think I'm going to try and figure out a spring loaded feeding system in the future.

*Tungsten issues:* So here is a link the "purple" Radnor e3 tungsten I've been using this entire time: Radnor E3 Home

If you remember, I was having some trouble with apparent cleanliness and (lack of) heat issues on my dropouts. With some of these ornery welds still incomplete, I ran out of tungsten. Forced to buy from the only shop that was open, I went with what they had: 1.5% lanthinated tungsten. Expecting more of the same, I started finishing up some of these difficult welds. All I can say is that it was a HUGE, HUGE difference. The puddle would go right where I angled the torch, it seemed much less finicky, and WAAAY less prone to random (no contact) contamination which I had been struggling with. I basically can't believe it. So I don't think I'll be using the purple e3 tungsten the Airgas store sells anymore. I wish I would have found this out sooner!

*Bike Assembly:* The bike assembled pretty easily. I wound up filing the driveside dropout slightly to align the wheel as Peter suggested a long time ago! The brakes aligned easily, and the derailleur seems to hang straight and shifts well! This was initially meant to be a super cheap build, but the more I got into it, the less I wanted to hang really bad parts on something that I have worked so hard on. So I reverted to my budget oriented, but functional building ways. One place I saved money was on a NOS sram x9 shifting setup. Probably ten years old, it shifts pretty well. I rigged (by grinding a bunch of tabs off) a 40t wolftooth sprocket onto the back of an 11-34 shimano cassette, and it's running about as smoothly as one could expect.

*First ride:* I took it out on some local xc trails, and must say it was pretty gratifying to ride a bike that I built! It was also a bit anti-climactic, since it doesn't completely blow my socks off geometry-wise. With a 70mm stem, the top tub is long feeling! I designed it that way on purpose, but still surprised me! It absolutely hauls butt on flattish to uphill sections and is comfortable on the downhills, but without much give, I'm not sure how useful the aggressive geometry will be. However, these trails are pretty techy, so I'm thinking it will be a better fit for some of the smoother downhill options.

*Next Steps:* When I stand up and crank hard (one of the big things I want to do on this bike) I can really feel the rear end flex. I'm thinking about adding a gusset behind the ST to BB to help with this.

Also was able to see that my cable guides need some slight adjusting, so I'll be tidying that up a bit.

After all this, I think the final step is paint?

Here's a couple of pics!:

















Thanks again for all of the help. As always, love any input from you guys- looking forward to getting some paint on this bad-boy!


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## KENdaman (Jun 30, 2014)

*Wow!*



thedudeman said:


> Sorry to anyone who was paying attention and especially those who have helped me so much for the huge delay. Learning how to do house projects like new hardwood floors, and actually riding bikes have taken priority for a while. TL;DR: scroll to the bottom for pics of where I'm at
> 
> So here goes:
> 
> ...


Awesome bike! Just read a majority of the pages, and was really impressed. For the past year I have thought how it would be really incredible to build my own bike, now im just pumped to do so. Thanks for the inspiration to complete my idea! 

What color are you thinking of doing?


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## thedudeman (Nov 10, 2006)

KENdaman said:


> Awesome bike! Just read a majority of the pages, and was really impressed. For the past year I have thought how it would be really incredible to build my own bike, now im just pumped to do so. Thanks for the inspiration to complete my idea! 
> 
> What color are you thinking of doing?


Well thanks! I must give all credit to the amazingly generous people on this forum who kept me going- I'm fairly certain I would have scrapped a frame or five without these folks.

I like how it looks, so for color, I'm actually thinking silver. I could be swayed, and may be at the mercy of what I'd available for powdercoat around these parts!


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## Eric Malcolm (Dec 18, 2011)

Scott

There is nothing more satisfying than riding your own hand-built bike, and it looks good too.

Regarding the flex, I would say, relax, its the nature of steel to move a little. The idea of gusseting in the manner that you suggest is flawed, don't do it.

While I have not used this particular Chainstay that you have used, I will explain in general what is going on.

Firstly, a 25mm C/S is pretty meaty, and at .9/.6mm wall, larger than anything you're likely to come across in general. The .9mm section is at the BB end, and the .6mm usually is found in the tapering part of the stay. With a profile of 33 x 15.5mm cross section, the vertical plane is under no threat as flex would be very minimal, keeping in mind that this area is fully triangulated. The 15.5mm part of the oval is where you will find potential flex, which translates to sideways flex. (Please note that when riding, a wheel with poorly tensioned spokes and a tire that is low pressured can mimic frame flex). If you happened to give the drop-outs a wee squeeze together to feel the tension after you welded the CS to the BB you will have noted a real nice tension. Now that you have a completed frame you can still remove the rear wheel and feel for that resistance. Compare it to other bikes you can try out and see how it compares. I would almost bet that your frame will compare well against others. An experienced builder will be able to establish this feel if they follow an interest in such things. This is one of those acquired over time experiences, so you will need accept what you have. I am not sure if you could have made it much stiffer with what is available however. If you do some testing, take note of the movement along the stays length, being tapered it should be consistent through-out the length, but if you feel that it is a bit bendy at a certain point, mark it with a pen and picture the area for us to look at. I do feel that you will be fine though.

Eric


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## Eric Malcolm (Dec 18, 2011)

Hey Scott

Just looked back over this whole thread (should have done that fully before above answer). DUH!!! Old age blowing the memory like a sieve. To recap, you attached the seat tube to the DT just above the BB shell. That does change the scenario a bit. Help, I wasted all that learning for nothing, LOL. 

Now to contradict myself, as I love to play with non-conventional approaches, and say Yes, do a gusset. I suggest tubing over a plate as you're trying to stop a likely BB rotation rather than a CS flex. Do you have any 16mm material/off-cut you could mitre in similar to the way rear disc brake supports are done? As noted above, your CS's are pretty meaty, and orientated to attach a gusset readily, and the ST is also able to take this load. The ST is intended to do this load task anyway in a conventional layout.

Eric


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## thedudeman (Nov 10, 2006)

Hi Eric- thanks for the input! I like the idea of gussets you have- I'd never thought of that... I was actually considering making a 1.375" tubular gusset that hits the ST/BB/DT and is a couple inches long- kind of restoring where the ST would normally hit the BB. It looks like it would be a bear to create all of those coping cuts, but is a relatively small amount of tubing. 
I believe I do still have some 16mm tubing to do gussets like you're talking about, so I'll look into doing them that way as well. It will be kind of nice with the bike together, since I'll be able to just hold stuff up to it and see what I can patch on there! (kidding, not a huge gusset fan, personally, but I think it could help a lot in this case)

Scott

edit- I think bent seat tube would be the way to go in the future.


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## Eric Malcolm (Dec 18, 2011)

Quote: I think bent seat tube would be the way to go in the future.

Yep, but you got to start somewhere.

Eric


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## thedudeman (Nov 10, 2006)

*longest frame build ever?!?*

So my "test build" phase lasted waaaaaaay longer than it should have... But I got to ride the bike a bunch, and ride my other bikes during summer, so that was great! 
Anyway, I finally got back to addressing the two issues I had: 1. cable guides in the center of the TT and 2. adding a gusset to reduce flex at the BB. I decided to go with a tubular gusset to keep the look of it fairly inconspicuous, and it was pretty fun/challenging to build with all of the different tubes intersecting at the same place. Next up is powdercoat, and I'm not putting it together until that's done!


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## ktm520 (Apr 21, 2004)

Nice work man! Have you rode it since adding the bb gusset?


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## thedudeman (Nov 10, 2006)

Well thanks ! I haven't ridden it yet, but I'll definitely report back whether or not I can notice a difference with the gusset.


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## thedudeman (Nov 10, 2006)

*Paintttttttttt*

I just picked up my bike from powdercoat, and had a blast putting it together using the proper cable clamps, etc. Pedaling hard around the driveway I can a noticeable reduction twisting/flexing at the BB, so I think the tube gusset did some good!


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## Eric Malcolm (Dec 18, 2011)

Hey, great build, lots of learning and well done.

Eric


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## thedudeman (Nov 10, 2006)

Eric Malcolm said:


> Hey, great build, lots of learning and well done.
> 
> Eric


Thanks Eric, 
And thank you for the help along the way 
Scott


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## cable_actuated (Jun 7, 2012)

Interesting that you think the gusset added significant stiffness to the bike. I have a similar configuration for the seat tube on my last frame save for a straight 35 mm 9-6-9 down tube. I don't feel a lot of flex from the BB shell or rear end, but I don't usually push frames to their limit at my weight. I was thinking that those massive Nova chain stays spread wide on the BB shell and paired with a short rear end would cut down on flex. So far, that's what my experience is. 

Looks great with paint!


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## thedudeman (Nov 10, 2006)

Most of the trails I've ridden so far are pretty techy and short climbs/descents, which makes quick out of saddle efforts pretty common (not to mention I'm a LEAN #200, well kind of...). 

I may not notice it as much if I was on smoother trails where I could just spin more often. Previously, under me, it was pretty flexy. It still flexes, but I can definitely feel that it's reduced with the gusset.


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## ru-tang (May 20, 2009)

I am curious about the geometry and how you like it. I've been thinking of a bike with some similar numbers. If I remember from reading your thread a while back: A slack short travel 29er? 

I wonder if a slack HTA needs to be paired with more travel . . .


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## thedudeman (Nov 10, 2006)

Here are my thoughts on why I went with the 67 HA paired with the 100mm fork:

I designed the 67 HA assuming roughly one inch of sag, ending up at a roughly 68 dynamic angle, to put in the range of the full suspension bikes I like in the category. 

I went with 100mm since I figured I could run a little less air to get more compliance without feeling like the front end is diving a ridiculous amount (compression on these xc forks seems to be about equivalent to adding air pressure in my opinion). Basically, I view this fork as a tool to take the edge off, not really be great suspension.

From the riding I've done on it, I feel like it does what I want it to. It's compliant, but the feel of the bike doesn't change too much as I ride. 

I actually like the feel of a slack HA with that wheel way out there. It's confidence inspiring, and I never view it as much of a hindrance. However, how necessary is it? I don't know. Lack of travel is going to start to be a limiting factor for going fast through rough, and where does the added stability benefit stop mattering because the rider isn't willing to monster truck over rough at high speed with 100mm travel?


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