# Frame #3



## golden boy (Oct 29, 2008)

Currently under construction. I'll start with the design drawing:









Cripes...does it really look as small as it does in my preview?


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## golden boy (Oct 29, 2008)

Well, at least you can click on it to view a slightly larger version. If you're not too old, you might even be able to read the dims.

The intent of this frame design is an all-around mtb hardtail. It's not a radical departure from frame #1, but I want to improve upon the following shortcomings of that frame:

1. Rear triangle lacks tire clearance. Even with a 2.1 Neo-Moto mounted, the rear wheel has rubbed the stays to a nice, polished steel. As you can see, my drawing does not show the stays. They're difficult to model in Solidworks. This part of the design will evolve on the fly as I build it. I have some stays I *think* will work for me.

2. Rear triangle does not allow for a front derailleur. As the design stands now, the chainstay length is identical to frame #1 (420mm). That might change as the build progresses. What is different about this design is an increase in seat tube angle from 72 to 73. Also, I bought a direct mount doohickey from Clockwork. That, along with the direct mount 2x XT front derailleur I have on order will hopefully provide rear tire clearance. If not, I'll bump up the chainstay length as needed, hopefully no more than 425 mm. I looove how playful frame #1 feels, and I think the short stays play a big role.

Other notable changes from frame #1:

3. My first frame to not use the Nova externally-butted seat tube. Time to grow a little as a builder. I'm using the True Temper RC2ST with external 4130 sleeve. This arrangement allows for a greater range of seat tube length as well as a thicker wall at the seatpost insertion point for increased durability. The slightly-larger diameter will also help at least a little in my quest for increased rear tire clearance, since I can spread the seatstays a tiny bit wider.

4. 44mm head tube. Considered PMW's version, but as per my recent post here, going with the TT version for this one. Time to join the tapered steerer ranks, even though I'm only planning on using a 120mm fork.

5. Larger diameter top and down tubes. Sticking with .8/.5/.8, but bumping up these tubes one size, to 31.8 and 34.9mm, respectively. For me and my riding style, I thought frame #1 rode beautifully, super comfy but not squirelly. It'll be interesting to see if I notice the difference in ride quality. Part of the fun of building my own frames, getting to experiment with all the variables that go into a frame and ride the results.

6. Lastly, first build using PMW low-mount rear dropouts. Cuz I like the look of the brake caliper mounted within the rear triangle.

More to come...comments and questions are welcomed!


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## golden boy (Oct 29, 2008)

*Cutting the head tube to length*

This is how you all do it, right?


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## briderdt (Dec 14, 2012)

Close enough. Then it gets cleaned up with the reamer/facer after the build. Leave a little excess when hacking.


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## shirk (Mar 24, 2004)

The kitchen is the best place for bike building.


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## Eric Malcolm (Dec 18, 2011)

shirk said:


> The kitchen is the best place for bike building.


Many a divorce started this way..........

Eric


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## golden boy (Oct 29, 2008)

Actually, I was going to say...my wife is the best. When I asked her if I could use the kitchen island to hacksaw some steel tubing, she didn't even bat an eye! :thumbsup:


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## cable_actuated (Jun 7, 2012)

We should have another thread for kitchen frame building shots. I have a few!

Frame design looks like it should be fun. I'm a little skeptical that a seat tube sleeve is going to get you significantly more seatstay clearance. I've settled on alternative methods of attachment for my really small frames. Didn't you do a partial capped seatstay configuration on your last bike? Didn't like how that worked?


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## golden boy (Oct 29, 2008)

cable_actuated said:


> I'm a little skeptical that a seat tube sleeve is going to get you significantly more seatstay clearance. I've settled on alternative methods of attachment for my really small frames. Didn't you do a partial capped seatstay configuration on your last bike? Didn't like how that worked?


You're correct, the sleeve won't get me a significant amount. But every little bit helps. Good memory on my last build. That worked out OK. It still doesn't offer loads of tire clearance. I am determined with this build to get even more, whatever it takes. That's part of the reason my CAD model is incomplete. The seatstay configuration is still very much up in the air. I have some Columbus stays that I'm hopeful will help with this goal. Don't remember the part numbers off the top of my head. Stay tuned!


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## golden boy (Oct 29, 2008)

*Proceeding at a turtle's pace*

Frame #3 is out of the jig now. It's always exciting to hold it in your hands for the first time. Here's a shot of the untouched fillet braze of the head tube junction:


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## Eric Malcolm (Dec 18, 2011)

Nice. Brazing is looking more even. Not too much filing to clean up.

Did you do your 'cooking' in the kitchen? LOL.

Eric


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## golden boy (Oct 29, 2008)

Thanks for noticing, Eric! I do think my brazing's getting more even. Still too much file time for my tastes. I'll post an 'after' photo when I'm done filing this area. Already have about 3 hours in.


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## MMcG (Jul 7, 2003)

I'll take one of these!  Just the right size for me!


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## G-reg (Jan 12, 2004)

shirk said:


> The kitchen is the best place for bike building.





Eric Malcolm said:


> Many a divorce started this way..........Eric


Both operationally tested in my case.

NON-ProTip, downstairs bathtub makes for an OK soak tank.

Even more NON-ProTip, should you decide to do a quick braze-on in the kitchen because you live in ND and it's F'n cold outside don't accidentally drop the lit torch on the linoleum floor....

*Edit* untouched HT looks nice! You should save your thumbs and go un-filed if you can pull that off on the rest of the frame.


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## Eric Malcolm (Dec 18, 2011)

NON-ProTip, downstairs bathtub makes for an OK soak tank. 

Even more NON-ProTip, should you decide to do a quick braze-on in the kitchen because you live in ND and it's F'n cold outside don't accidentally drop the lit torch on the linoleum floor....

Wow.....I got my learning at an early age when I dropped a hot soldering iron onto the floor, my mother taught me real good!!!! I come from an earlier time that was not PC and nanny soft....

Eric


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## golden boy (Oct 29, 2008)

Rest assured, I draw the line at brazing in the kitchen. The kitchen is for cooking hash oil. This is Colorado after all.

G-reg, kinda wish I had left the fillet untouched! How did you know filing makes my thumbs hurt?

Alas, I succumbed to the file. Here's an after photo:









I've since filleted and filed the seat tube/top tube junction. I think I'm getting better at this! More photos soon...


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## TrailMaker (Sep 16, 2007)

And...

You have to learn to only file on the thick brass, and not its parent thin steel tubes, eh?


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## golden boy (Oct 29, 2008)

I'm farther along than this, falling behind on photos, but here's a couple shots of the raw brazed TT/ST junction.


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## golden boy (Oct 29, 2008)

*Acceptable range on rear dropout spacing?*

My frame is brazed together except for the seatstays. Currently the rear dropout spacing measures 131mm. Rear wheel uses a 135mm hub. Is this acceptable? I have tried cold-setting to increase the spacing, to no avail. I have heard of witch-wanding, but even with research I don't feel like I really understand this process.

Even if 131mm spacing is OK now (rear wheel slides in without too much difficulty) I fear that adding the seatstays and bridge will pull the dropouts in further and make it difficult to insert the rear wheel.

Thoughts?


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## G-reg (Jan 12, 2004)

One newb to another... A few mm off on the hub spacing isn't a huge deal. But are you positive that is the only way the drop positioning is out of alignment? Because a being a few mm off on the dropouts in nearly every other plane will be a big deal. 

You should be able to cold set a few mm at the drop, again you have to ensure you keep things centered/in phase. You won't really be able to do this once SS/braces are on.

What are you using for a dummy axle? The Anvil ones are a few mm oversized, my 135 is actually 137mm, and once I pull the axle they usually end up right on 135. If you aren't using an Anvil dummy, just buy one. A bargain at 35$.

There's something about slamming in a rear wheel and having it fit nuts on, no fighting to spread the drops or using the qr to squeeze everything together.


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## golden boy (Oct 29, 2008)

Thanks G-reg. I'm using a 137mm Anvil dummy axle, but here's my confession: I used the dummy axle when I tacked the chainstays in the jig, of course, but I forgot to install the dummy axle when I fillet brazed the chainstays in my cheapo repair stand. Doh! I think that's when the stays pulled closer together.

I think I did improve the spread somewhat with cold setting, but without some sort of mechanical assistance I don't think I can cold set any further. I don't have an alignment table, but I do have and use the Park *** and DAG tools. True confessions part 2: assuming the head tube and seat tube are aligned, the *** indicates the rear dropouts are skewed to the drive side by 2-3 mm. I'd like to claim this was intentional, based on Walt's recent discussion of offsetting the rear to improve chainline, but alas, it was not. With respect to each other, I have used the DAG tool to align the dropouts very well.


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## golden boy (Oct 29, 2008)

Hah! I've been censored. Apparently MTBR doesn't take kindly to homosexual slurs. That would be the Park "frame alignment gauge." My apologies if I offended anyone.


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## DSaul (Dec 13, 2012)

I agree with Greg on making sure they are not out of alignment in any other plane. I know from experience that it will show up when you add the seat stays and there is no correcting it after that without cutting things off. My experience has been that chainstays are pretty easy to cold set as long as you have a fixture to hold the bottom bracket securely while you pull on them. If something is not right, now is the time to cut it off and fix it. Close enough, but misaligned, will annoy the heck out of you later.


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## Drew Diller (Jan 4, 2010)

golden boy said:


> Hah! I've been censored. Apparently MTBR doesn't take kindly to homosexual slurs. That would be the Park "frame alignment gauge." My apologies if I offended anyone.


You don't need to apologize for a bone-headed name. I like Park and whatnot for the most part, but they should have seen the implications of this product name when they created it, and should have chosen something else.


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## dr.welby (Jan 6, 2004)

golden boy said:


> I think I did improve the spread somewhat with cold setting, but without some sort of mechanical assistance I don't think I can cold set any further.


Got a 2x4?


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## golden boy (Oct 29, 2008)

dr.welby said:


> Got a 2x4?


Thanks, Dr. Welby. I wasn't sure how to go about cold setting. Man, I love Sheldon Brown. He belongs in the bicycle hall of fame, if there is such a thing.


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## golden boy (Oct 29, 2008)

*An update on alignment issues*

One of the things I love about being a beginner builder is that with every frame I build, I learn a lot. I don't have an alignment table. But I do have a Journeyman frame jig. I figured that putting the frame back in the jig would show me where any alignment issues were. Please weigh in if my thinking is flawed.

So I faced and chased the bottom bracket and put the frame (sans seatstays) back in the jig. I positioned the seat tube cone and upper head tube cone so that they just hovered over the top of their respective frame tubes. Then I used a metric ruler to measure the amount of misalignment. It turns out the seat tube if off center 3mm to the non-drive side at the top of the tube; the head tube is 1.5mm off center to the drive side at the top of the tube. A big surprise to me was to see that the rear dropouts were actually perfectly centered, although the spacing is a bit on the narrow side. _So previous to this, when I used the Park frame alignment gauge, I mistakenly thought the rear dropouts were not centered, when in fact it was actually the twist between the head tube and seat tube giving me the wrong impression.
_

What a great lesson to learn! Using the Park tool by itself doesn't actually pinpoint the problem. Sooo glad I thought to use the jig as a stand-in for an alignment table. Now I need to decide if the head tube/seat tube twist is substantial enough to be concerned about (I think "yes"), and what to do about it. I'm still wanting to know what witch-wanding actually is. I think a trip to Anvil is in the cards this week.


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## dr.welby (Jan 6, 2004)

golden boy said:


> I'm still wanting to know what witch-wanding actually is.


There's a pictorial about it in Bicycle Quarterly Vol. 12 #4.

It's not that hard of a process - you heat a small section of the tube on the side you want it to move towards. More heat and area result in more movement.


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## golden boy (Oct 29, 2008)

dr.welby said:


> There's a pictorial about it in Bicycle Quarterly Vol. 12 #4.
> 
> It's not that hard of a process - you heat a small section of the tube on the side you want it to move towards. More heat and area result in more movement.


Love Bicycle Quarterly! You seem to have excellent taste in all things bike-related, Dr. W. I wish they featured more mtb content though.

So I think I'm ready to wing it on the witch-wanding. Do I need to flux the area to be heated? Seems like a good idea.


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## dr.welby (Jan 6, 2004)

golden boy said:


> Do I need to flux the area to be heated? Seems like a good idea.


The guy in BQ doesn't, and he's a master Keirin frame builder. I've never used flux in this application either, for whatever my meager credentials are worth.

It certainly wouldn't hurt, and it would only cost you a little flux and a little cleanup time. You can't flux the _inside_ of the tubing at this point so you're missing half of the 'protection'. And what are you accomplishing in the long run? A little surface oxidation isn't a big deal since it's not getting in the way of anything.


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## golden boy (Oct 29, 2008)

'kay then. No flux! Tomorrow I'll make the attempt and report back.


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## golden boy (Oct 29, 2008)

No pics, but the witch-wanding worked pretty well. Seat tube started out 3mm off-center to the non-drive side, and ended up .5mm off-center to the non-drive side. I did it in the frame jig so I could monitor the movement. One minor downside was that the fully fillet-brazed bronze at the BB junction slumped a bit. Overall though, I'm happy.


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## golden boy (Oct 29, 2008)

Oh - once I got the seat tube pretty well centered, I shut off the torch and immediately dropped the seat tube cone down into the top of the seat tube. Not sure if this helped keep it in position as the frame cooled, but it seemed like a good idea.


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## dr.welby (Jan 6, 2004)

golden boy said:


> One minor downside was that the fully fillet-brazed bronze at the BB junction slumped a bit.


Where did you put the heat? On the joint?


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## ktm520 (Apr 21, 2004)

Yes, more details please.


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## dr.welby (Jan 6, 2004)

You can just heat the tube. Near the joint probably gives you the most bang for your buck but you don't need to heat the joint itself (it's not going to go anywhere). But if you can't (like because there's a brazeon in the way) you can do it further towards the middle of the tube. What you're doing is inducing a little bow into the tubing. 

The technical details - when you heat up a spot, it wants to expand. But the colder tubing around it hasn't expanded so the hot spot has nowhere to go. So it distorts by expanding in the only direction it can - inwards and outwards. It might also 'smush' some of the less warm tubing around it. This is a permanent distortion, so when the metal cools down and contracts, the 'hole' it used to occupy is too big, and the cooling spot pulls the tubing in. This will cause a little bow in the tubing, and if it's done near a joint the majority of the tubing will stay straight. I've had to to do it in the middle of the tube and by spreading out the heat to distribute the adjustment I can't visually see any bow in the tube. YMMV, of course.

This also works for things like seatstay bridges. I don't think the bridge pulls in the dropouts closer - it can't unless it gets shorter. But the hot spot around the bridge causes the stay to bow inwards. A heat cycle on the outside of the stays can balance that out and return the dropouts outwards.


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## golden boy (Oct 29, 2008)

Yeah, I put the flame right on the fillet on the drive side of the BB junction. Cuz that's what I thought I was supposed to do. Turned out pretty well, I think.

Thanks for the info on the seatstays, Dr. W. That's the last piece of the puzzle for me.


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## briderdt (Dec 14, 2012)

Yeah, I wouldn't go re-heating a joint, but just up the tube a bit. No flux needed as you're not (or shouldn't be) heating the tube that much -- just a little up the orange color range, not molten at all.


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## golden boy (Oct 29, 2008)

Sorry for the lack of posts. The chainstays came out asymmetrical, and I cut the drive side seatstay in the wrong place and don't have tire clearance. Feeling discouraged...


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## life behind bars (May 24, 2014)

golden boy said:


> Sorry for the lack of posts. The chainstays came out asymmetrical, and I cut the drive side seatstay in the wrong place and don't have tire clearance. Feeling discouraged...


 You could make an attempt to salvage it with a wishbone or segmented seat stay possibly?


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## Christo (Mar 27, 2004)

I had a similar misalignement issue lately, and after reading this post i tried this witch-wanding solution. I don't have access to Bicycle Quarterly here in France, so it was really a new way to me. Front triangle came out really nice, you can see the pics on

Messy fillet brazing and (bad?) solution...

Cheers

Christophe
There's a pictorial about it in Vol. 12 #4.


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