# Questions about frame building, help a beginner out!



## Hack On Wheels (Apr 29, 2006)

Hi all,

I think this forum is now replacing the lights one as my favourite! Far too much eye-candy and lots of awesome designs! I've actually just joined a student design team at my university and while it is actually for building a small race car, the whole fabrication process in addition to wandering across this forum, has rejuvenated my interest in welding and my dream of building my own bike. Now, I have some specific questions for you guys, but I would also appreciate any wisdom that you think would help me, are there any bits of knowledge or advice that you wish you had been given before you embarked on making your first frame?

-design process: is drawing it out in detail adequate or is there a free or cheap program that you would recommend using?
-materials sourcing: no question at the moment, I don't know enough to start asking
-welding: I am thinking of taking a local TIG welding course, would a more general welding class be better? Also, I don't currently have access to welding equipment, any of you in the same situation what do/did you do?
-jigging/alignment: Currently I think this could be the single biggest obstacle/challenge for my frame building dream. What do you guys do for alignment?

There is much more that I could ask, but I think I will leave it there for now. Any info and help would be greatly appreciated.


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## pvd (Jan 4, 2006)

BikeCAD is what most people use, but since you are a student, you should be learning SolidWorks. Paper drafting is a joke. Rise up and learn the good stuff. this will help you get an internship at an engineering firm at the least.

best bet is to at least find access to any TIG machine you can and practice, practice, practice. A class is really good on top of this, but time on is most valuable.

Nova cycle supply has anything you will need. Paragon has fancy parts.

I wouldn't worry about jigging. Just buy a super cheap tubeset and do your best to hold parts in place and get 'em tacked. It'll suck, but getting the first bike out of the way is priceless.


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## D.F.L. (Jan 3, 2004)

Drafting a full-size paper drawing will work great.


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## rustola (Jan 15, 2008)

No need for a general welding class, just go straight for TIG. I was in your shoes back in the day and went straight for the TIG class, and I still don't know how to stick or MIG (or even braze for that matter). Practice, practice, practice - more than instruction you just need time to get the feel of it. When I was learning, I think I actually got more out of my own practicing/experimenting during open lab time.

My biggest piece of advice is to JUST DO IT. Like pvd says, buy a cheap tubeset (nova has a special on tubeset + BB + dropouts for $85 right now) and just go for it, expect that you're going to make mistakes, and learn from them. I overthought and overplanned my first frame and it took damn near 3 years to finish. Guess what, I still made all the mistakes, but they ended up being precious gems of learning.

Not sure about going totally jigless, but I agree that you don't need to be overly anal about alignment at first. Get some decent measuring tools (don't forget string!), and do your best - unless you make some gross error the bike will ride just fine. And you'll probably end up understanding better the purpose and function of a jig.

Good luck and keep us posted


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## BrendanC (Aug 11, 2005)

Just do it.
I built my first bike with a cruddy jig, with lots of shimming & clamping involved. It was a lot of fun, and perhaps the best way to learn what's what.
Draw that sucker on a big piece of paper.
Measure three times.
Cut once... or cut short, then pull out the files! ;-)
Align it with levers & lots of measurement- you'll need to find a surface plate or something else FLAT.
Be proud of it.


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## dr.welby (Jan 6, 2004)

You definitely don't need a fancy jig. You can do just fine with a good scrap pile of angle iron and some clever thinking. There are enough other things to screw up on that the lack of tolerance won't make a difference.

However, it is worth putting a little time into your fixtures. They don't have to be super accurate but they should at least be stable and dependable.

Here's an idea for something for the front triangle. My personal jigs leapfrogged this design so I can't say much about it in use. But it might give you some ideas.

A few things you'll notice is the use of levelling screws and welder's magnets. The screws let you get everything parallel and level, and magnets give you a way to hold a tube in place and still fine tune the position. The rest is all C-clamps and anything else you can scrounge up.

If you want to step it up a bit then there's my  current design 

It's more of a "real jig" but still stays pretty low-tech in the machining department.


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## Hack On Wheels (Apr 29, 2006)

pvd said:


> BikeCAD is what most people use, but since you are a student, you should be learning SolidWorks. Paper drafting is a joke. Rise up and learn the good stuff. this will help you get an internship at an engineering firm at the least.
> 
> best bet is to at least find access to any TIG machine you can and practice, practice, practice. A class is really good on top of this, but time on is most valuable.
> 
> ...


I have used Solidworks briefly, but I need practice and that trial version has expired. I'm hoping to have access to it again soon.

I think I will at least do some sketching for the time being, if nothing else, just in order to get my creativity going. And who doesn't like sketching bikes?

No idea where I can get access to a TIG welder, maybe if I am lucky I will be able to access one through the program I will be in next year.

Nova Cycles = standard stuff, Paragon = bling bling... good to know, thanks!

Don't worry about jigging? Yikes, that goes against all of my perfectionism... I would like to have at least a decent system for aligning pieces. It might be my first bike, but I want it to be rideable so I can use it and then tweak the geometry for the second attempt. A crooked frame would be annoying as heck to ride. I don't care how nasty the first try looks, but I want it to at least be decent function-wise.

Thanks for all the advice, pvd (and everyone else)! This is a great help, and any further input is very welcome!


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## Hack On Wheels (Apr 29, 2006)

dr.welby said:


> You definitely don't need a fancy jig. You can do just fine with a good scrap pile of angle iron and some clever thinking. There are enough other things to screw up on that the lack of tolerance won't make a difference.
> 
> However, it is worth putting a little time into your fixtures. They don't have to be super accurate but they should at least be stable and dependable.
> 
> ...


Brilliant! Thank you very much, this is exactly the kind of thing I was hoping for!

I'm definitely not planning to invest in an expensive jig right away, but this sounds like a great option.


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## dr.welby (Jan 6, 2004)

Your university may have welding classes. Sometimes they're part of engineering, sometimes they put them in the agricultural departments. If your school has an art center, they may have torches for metalworking classes that you can use too.

Also don't forget to check at the nearest community college.

If you need a free 3d Solid Modeler, try Alibre. It's pretty darn good for free.

Also, you did read the FAQ (first post in the forum), right?


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## Hack On Wheels (Apr 29, 2006)

dr.welby said:


> Your university may have welding classes. Sometimes they're part of engineering, sometimes they put them in the agricultural departments. If your school has an art center, they may have torches for metalworking classes that you can use too.
> 
> Also don't forget to check at the nearest community college.
> 
> ...


Unfortunately, no welding classes that I am aware of, I will double check though. Luckily there is a technical/trades school nearby that offers many welding courses, not cheap though.

I might just try Alibre, thanks. However, after thinking about it a bit, Solidworks ( might be more of a pain than a help for a simple hardtail.

Oh dear, no, I didn't read it. I think that would have been a bit too obvious. I read a lot of other threads and did a search for jig stuff, yet I didn't think to look at the sticky! Thanks for pointing it out.


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## CBaron (May 7, 2004)

Hack-

This topic came up on one of the local forums I frequent. Below is a cut-n-paste of the info that I left on the other forum.

-----------------------------

_Where do I begin......

I lived in Dallas from 02-05' and I regularly frequented this board. So here I am back glimpsing through the forums just to see whats up. I'm now in Austin and began building bike frames part-time (with 2 other partners) about 2 years ago. If you want to learn more details about our story then go here... www.truefabricationbicycles.com

I'd be very willing to give you some pointers and tips on how to accomplish your frame build. Since I don't come here to frequently it would be best to email me offline or feel free to call. There is so much more to it than I had ever imagined. But here are a few nuggests:

-We learned to weld with TIG and started wthl small thin tubes so I have nothing to compare it to. It took us over 6 mos of "playing" before we thought we had the skill to weld a rideable frame. I've heard MANY say that welding plate, or thicker gauge is no where near the same as thin tubing (sub 1 mm walled tubes). We've are now capable of .6 mm walled tube welding with no issues. FYI- TIG is pretty much the only way to build a "quality" frame. MIG is possible but it will look like poo.

-A good jig is important, but a cheap one could be made for a single use purpose of getting 1 frame built. A frame will spend an alarmingly short time in the jig. Just to check fitment, angles, be tacked and its done. The welding happens out of the jig. This leads me to welding sequence. We forged our own from MUCH trail and error. Every place you apply heat (1400 degrees) with the torch, the frame will bend to that direction. Each junction gets about 4 weld sequences (1/4 turn each pass on a tube equals a completely welded junction). Therefore there are about 16 passes alone on just the front triangle. Each pass resulting in the frame being "pulled" in that direction from the heat. THUS MOST EVERYONE ENDS UP WITH A BENT TWISTED PRETZEL OF A FRAME THEIR FIRST TIME. Once you learn how to play the bend you then end up with (Semi) straight frames. Remember I"m only talking about front triangle. Same goes for rear end but you also have to deal with alignment parameters from the front axle plane, heat tube plane, ST plane, and rear axle plane. So even if your welding sequence is down you need to make sure your "alignement" is sound.

-Miters and filing are very important. If your trying to weld joints that have big gaps then you will have much greater issues with the above stuff. Everything could be hand filed and many do it this way. But be prepared to spend enormous amounts of time filing. We have 2 mills and all of our touch up is done by hand filing. Once you get down to the final filing strokes its amazing how liitle of a stroke can remove material in the wrong place...thus causing gaps...welding issues....frame fab deflection.

My suggestion would be to practice welding thin walled tubes, work on mitering different angles, working to get the welding torch into tough places (HT/TT/DT junction is a mutha to weld), make a basic cheap jig (wood is even possible to use) and last DO NOT EXPECT to ride your first frame. Once the first one is complete....move immediately into the 2nd. You will have learned so much via the first one that your 2nd frame will be 300% better (and still not straight, pretty, or light)

Side note: 
Frame building schools- One of my partners when to UBI and did the multi-week TIG course. He came back with what we consider our *first* frame. He learned a lot and had the chance to go soup-to-nuts with it. However, he (we) had already been welding and mitering for over 6 mos by then. He was a head of the curve based on the other students.

Summary, I had been a 12+ year cyclist and student of bicycles, I had been a competitive racer, worked at 3 different shops over the years and thought I knew *something* about bikes. Once we actaully started frame building I realized just how little I actually knew. We've come a long way and can turn out quality product but it has been a painstaking road. If I can help you short cut any of your learning curve feel free to drop me a line. _


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## dr.welby (Jan 6, 2004)

Hack On Wheels said:


> I might just try Alibre, thanks. However, after thinking about it a bit, Solidworks ( might be more of a pain than a help for a simple hardtail.


I think PVD was suggesting Solidworks not for designing your frames, but for a skill you should gain a lot of competence in before you're done with school. For designing frames it's overkill.

You should probably learn Autocad too, since it's still used a lot across a lot of industries. You'll find it much more useful for laying out your frames.

This all assumes, of course, that you're majoring in mechanical engineering....


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## pvd (Jan 4, 2006)

CBaron said:


> _I had been a 12+ year cyclist and student of bicycles, I had been a competitive racer, worked at 3 different shops over the years and thought I knew *something* about bikes. Once we actaully started frame building I realized just how little I actually knew._


It really is funny how much people think they know about bikes untill they have to actually make some real decisions while designing one. I hear all the time about how things 'should' be from people that have never 'done it'. They think that they know about it since they have been around them for so long. Once you start realizing how little you know, then you can truely start learning. Frame design starts that process.

It's funny. I had one of our physics phd's in the shop today. We were talking about dry ice production. He said he came down to see what we thought about it since we tend to have good insite on the real world. I jokingly said that I had all the answers and that he didn't since he is actually so much smarter than me. It really is funny. The more you know, the more you know you don't know. Bicycle design becomes more and more a mystery to me the more I know about it.


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## Hack On Wheels (Apr 29, 2006)

Thanks CBaron! If I decided to buy a cheap jig, what are the options?

dr.welby:
That would make a lot of sense, good observation there.

Hmm, Autocad would be good, not sure where I would get a copy though. 

I'm aiming at mechanical, though I might go for mechatronics.


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## BeatAFool (Jan 14, 2008)

Do it jigless!!!!!! You'll learn SOOO much more. A jig won't keep a frame straight. I built my first frame on a granite countertop with blocks and shims. It's not that bad outa aligned....really. All my problems had NOTHING to do with the setup and everything to do with my miters and welding...................... Frame #2 is closer and I hope #3 is even better.


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## pvd (Jan 4, 2006)

I would spend the money to buy a student version of SolidWorks long before buying a jig. It's a waste of money for your first frame and learning to use a parametric CAD package is an investment in your future that will pay you back with unlocked doors and some spending money. These days, nobody is using AutoCAD unless they are a dinosaur or an architect. It's nice to know (especially for cleaning polylines for laser or water cutting) but it's really a waste of time in the modern era. Parasolid files are just too dam usefull and parametrics save so much time and improve design quality.

If you are in school, you should be able to purchase several CAD packages at education prices. Talk to your instructors.

Again, a concrete floor and super cheap tubes are fine for #1. Just design well and measure things better. A nice 1000mm flexible steel rule make a ton of difference.


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## indrek (Feb 16, 2004)

Here is my latest jig design (SolidEdge). It has all the necessary adjustment possibilities and is made of standard U beams, Al and steel plates. Should be very accurate








And a little pic with a bike attached








Although to be honest for the first jig I'm actually planing to build something similar to dr.welby's design.


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## surlytman (Nov 9, 2005)

I see red X's


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## indrek (Feb 16, 2004)

...should be ok now


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## Hack On Wheels (Apr 29, 2006)

BeatAFool said:


> Do it jigless!!!!!! You'll learn SOOO much more. A jig won't keep a frame straight. I built my first frame on a granite countertop with blocks and shims. It's not that bad outa aligned....really. All my problems had NOTHING to do with the setup and everything to do with my miters and welding...................... Frame #2 is closer and I hope #3 is even better.


I'm still not sold on going jigless. I'd like to have at least some kind of system to assist with alignment and holding tubes in place when tacking. I'd imagine that the rear triangle would be especially difficult without any kind of assistance. If I can eliminate a source of error, then so much the better.

On a sidenote: How much will/would I have to worry about warping the frame with TIG welding?


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## Hack On Wheels (Apr 29, 2006)

pvd said:


> I would spend the money to buy a student version of SolidWorks long before buying a jig. It's a waste of money for your first frame and learning to use a parametric CAD package is an investment in your future that will pay you back with unlocked doors and some spending money. These days, nobody is using AutoCAD unless they are a dinosaur or an architect. It's nice to know (especially for cleaning polylines for laser or water cutting) but it's really a waste of time in the modern era. Parasolid files are just too dam usefull and parametrics save so much time and improve design quality.
> 
> If you are in school, you should be able to purchase several CAD packages at education prices. Talk to your instructors.
> 
> Again, a concrete floor and super cheap tubes are fine for #1. Just design well and measure things better. A nice 1000mm flexible steel rule make a ton of difference.


Well, I'm hoping that I will be able to get a license for Solidworks via the team that I am on. It should happen in a few weeks if all goes well.

Concrete floor? My inner perfectionist just fainted at the thought... 
I think I will see if there is any simple and (relatively) cheap way to get better accuracy, or at least assist it.

The ruler would be great to have though, thanks for mentioning that! I guess some flexible and not very stretchy string/wire could also help with some more awkward measurements.


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## pvd (Jan 4, 2006)

The thing about making your first frame is that there are lots and lots of special tools and skills that are needed: bb taps, seat tube reamers, head tube reamers, brazing torches, special filler wire and silver. It's going to all add up and get pretty overwhelming at first. That's why you should not get too worried about too much perfection at each stage. A concrete floor really is good enough at this point. Better is of course better, but getting too bent out of shape about it is going to take any fun out of the project.

Getting a functional, ridable bike is going to be tough enough. Keep things as simple as you can for the first bike. figure out what needs to be made better later and make all the mistakes you can. On #2, then you can start going more nuts, but overcoming the inertia of the project is the most important thing about #1.

On TIG welded bikes, reaming the seat tube is going to be your #1 challenge.


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## Hack On Wheels (Apr 29, 2006)

pvd said:


> The thing about making your first frame is that there are lots and lots of special tools and skills that are needed: bb taps, seat tube reamers, head tube reamers, brazing torches, special filler wire and silver. It's going to all add up and get pretty overwhelming at first. That's why you should not get too worried about too much perfection at each stage. A concrete floor really is good enough at this point. Better is of course better, but getting too bent out of shape about it is going to take any fun out of the project.
> 
> Getting a functional, ridable bike is going to be tough enough. Keep things as simple as you can for the first bike. figure out what needs to be made better later and make all the mistakes you can. On #2, then you can start going more nuts, but overcoming the inertia of the project is the most important thing about #1.
> 
> On TIG welded bikes, reaming the seat tube is going to be your #1 challenge.


Oh geez, I see what you mean... I guess I might just have to get started to really see how to do it (which will have to wait at least a few months unfortunately).

Ridable would be awesome as my old hardtail frame is done, but I don't get the sense I will be likely to make a ridable bike very soon...

Excuse the ignorance, why does it need to be reamed, and why is this the biggest challenge when dealing with TIG?


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## heeler (Feb 13, 2004)

Needs to be reamed to size it for the seatpost (distortion from welding, etc...) The hardest part about Tig is developing talent.

I am a pipe engineer by trade and a welding inspector as well. I worked in a plant for a long while and we did a TON of stainless tig welding. During X-ray I would try to tig on scraps or cut outs with the help of expert welders on nice thick stainless piping, which has to be easier than thin wall tubing....ummm, no can do. It requires that you have two right hands apparently. If I ever build a bike it will have to be out of well casing and joined with SMAW...cuase that is all I can weld.


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## Treybiker (Jan 6, 2004)

I'd like to guess. Probably because you are welding 3 tubes to the seat tube (top tube, and 2 seatstays), which will cover about 75% of that tubes diameter in the same area. Tig welding will cause the tube to deform form all sides in that area so you would probably never get a seatpost in it otherwise. I know I've seen on some aluminum frames where it was welded that it seemed the weld penetrated the inside of the tube.


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## rustola (Jan 15, 2008)

pvd said:


> overcoming the inertia of the project is the most important thing about #1.


word.


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