zake

Hi All,

Just thought I'd run my plans past a more experienced group so that I go into this project with more know-how.

My friend has a State Bicycles Trooper 4.0 fixie that he uses as his commuter in Berkeley (CA). It has drop bars and track bike geometry (size 52cm) with a flip-flop hub and horizontal dropouts. The bottom bracket and head tube are threaded.
Geometry can be found online if interested.

I am a mechanical engineer student with an automotive background and have recently gotten a milling machine and oxy acetylene setup in my home garage, and my coworker has a professional-grade frame jig that he is willing to lend me. I have never built a bike frame but I do have some experience with fabrication.
The plan is to swap all of the components from my friend's bike (including fork) onto a new frame designed and built by me. The only significant departure from their design is to include an integrated seatpost-- i.e. one size fits one.

We are planning to copy the geometry of his bike, but use 4130 tubing and brass (bronze???) fillet braze the joints. He is an occasional road/crit racer but being that this is his commuter, frame sturdiness should be paramount to ride/handling/weight.

It would be great to get a nice step by step process of what to do- the best I have found so far is on the Wold Cycles website. (URL cannot be included-- sorry!)
This is more of an overview, so it would be nice to get a bit more detailed- for example how much of a gap should I leave between the mitered tube and the tube it is going to be brazed to?

I want to build this frame to practice my fabrication skills and try something new, so I aim to keep the cost low and design simple.
Given my lack of experience regarding framebuilding, what advice would you give me? Any suggestions would be great. Also, material/parts choice are still in the air, so any comments regarding butted/straight tubing, filler material, flux, vendors, etc would be welcomed.

Thanks,
Zack

JohnDThompson 

Unless you have some experience with fillet brazing, I'd suggest building a lugged frame as your first attempt. Ceeway has a basic frame kit you can buy with pretty much everything you need in terms of tubing, fittings, etc.:

Tube and Parts Bundle

David Tollefson

Before you touch flame to those tubes, get a bunch of tube ends (Aircraft Spruce sells boxes of grab-bag tube ends) to practice with. Practice your miters. Practice fillets on multiple angles. Find out how difficult it can be to control the heat and flow of the bronze. Get comfortable with flicking the flame onto and off of the joint. Use a lot of flux. Then, when you're comfortable with all that, run a set of 10 more fillets before you start in on the frame tubes.

niknak

Since you're a student, maybe you could convince your engineering department to allow you to get credit to take a proper framebuilding class from the likes of UBI, Doug Fattic, Dave Bohm, or Yamaguchi. The classes are typically an intensive two weeks. You'd gain so much more knowledge than poking around the internet. Framebuilding is simultaneously simple and extremely challenging. Getting a proper education is worth it.

fietsbob

1st master the fillet brazing skill . then consider applying it to hear sensitive thin wall tubing..

I built with a more tolerant Columbus straight gage ,

with lugs 1974, took Jewelry and art metalsmithing classes
to practice skills with the torch ..

and make non bike art objects..



...

mrv 

there's a youtube series called Pithy Bikes where the builder outlines his whole process - and he's a beginner at the start. I have NO IDEA (surprised by clueless advice over the internet?) if he's competent or not.
But maybe you can catch some things not to do.

https://www.youtube.com/channel/UCqQ...E0VEy9Q/videos

Andrew R Stewart 

+1 for this bolded comment. I've learned what not to do sometimes when repairing a broken frame Andy

unterhausen

what is it about framebuilding that leads people to try to teach after (or even during) their first frame build? Anyone ever seen one of Talbot's frames in the wild?

Doug Fattic 

Talbot wrote a book on how to build a frame in the early 80’s in the same way someone would approach writing a research project about a new subject. He contacted some American builders like Freddy Parr for frame building knowledge at a time when our craft was in its infancy this side of the Atlantic. He was a writer looking for a subject so he could publish a book. He was not a builder explaining his methods but rather trying out what he heard from others and then adding his own interpretation. The frame he used for pictures in his book was the 1st frame he had ever built. This was a subject with a chance for a decent market because the US bike boom was fairly new (when American adults finally discovered riding bicycles was fun instead of being just for kids before they could get a driver’s license) and there was little information available. I was pretty critical of it at the time and my opinion has not improved over the years. It wasn’t without value but a beginner would not know which parts were not good advice.

unterhausen

somebody borrowed my copy of Talbot and never gave it back. I still resent that even though I didn't like it that much.

It irks me that he used "P.E." in the byline of his book; it implies a level of expertise that he didn't possess. As a bike mechanic, I always laughed at engineers that thought that qualified them to work on bikes, and I laugh even more at engineers that think that qualifies them to build frames. The subtle things about building a good frame are not obvious to an engineer without a lot of study. Pretty much just like everyone else. If I wrote such a book, I would not put Ph.D. in the title, I didn't learn to build frames in engineering school. Although I did study things that would help.

Nessism

Some guy from here stole both my Talbot and Paterek books, along with some lugs. I loaned them to him because he was local and promised to return them and pay me for the lugs. Lesson learned.

I built my first few frames using a Talbot style jig and it helped me quite a bit. I'm a mechanical engineer and don't have a problem with him using his PE designation, although it strikes me as a little egotistical. Getting a PE is no easy feat so can't fault him though.

unterhausen

I am also a mechanical engineer. I would say that a Ph.D. is harder to get than a P.E. and I still don't throw my title around if I'm not working in my field of expertise.

I know I got some ideas from talbot's book, as well as the Proteus pamphlet. Paterek hadn't showed up yet. I have never looked at his book. I asked to borrow a friend's copy of Talbot so I could critique it better, but I think he was put off by my promise to burn it when I'm done. My philosophy is that everyone has something to teach me. I think I was in a sour mood the other day when Talbot came up on facebook. There wasn't an internet around when he wrote his book, so it took some initiative to go out and find a framebuilder to help him. Although, maybe Eiesentraut was teaching classes, that might have been a better start

JohnDThompson 

FWIW, Paterek has an older edition of his book available as a free PDF download on his web site:

https://www.timpaterek.com/paterek.pdf

Doug Fattic 

I dusted off my 1st edition printing of Richard Talbot’s "Designing and Building your own Frameset" that came out in 1979 to give it a fresh look. On the one hand I am impressed that someone with no prior building experience researching a fairly new American craft could do so well with some (but not all) of the concepts. On the other hand what knowledge is available now leaves it very dated and inadequate by today’s standard. Things like printing off mitering templates where not known back then. The worst problem in the book is its explanation of how to build the rear triangle. There is little hope a rear wheel will center following his methods. Other inadequacies include too much detail on some subjects like the many Harris silver brazing rods when only we need to know which one to choose. And just giving us general outlines but not telling us specifically how to align, braze and file. Of course I am probably harsher than many reviewers because of my background learning from a European master that knew exactly what to do and writing and rewriting my own frame building class manual over time. Years and years of refinement is a huge advantage. For example rookies almost always make the same mistakes and it is very helpful to know what they are and how to avoid them. To his credit Talbot did say it is best to learn from a master how to braze. In the appendix he listed 60 American builders including myself. A few others are still around but some have passed or retired. Ultimately this is a interesting historical document but should not be used as primary source on how to build a frame.

unterhausen

Well Doug, the book can't be all bad if it mentioned you. Maybe I'll find a copy at a used book store.

The other day, I was rolling some main triangle tubes on my granite table to find the bow in them wondering if Talbot ever found out you should do that before mitering. Then again, two of my tubes didn't have appreciable bow. Columbus is the best.

Broke Joke

Great advise here! I'm learning everyday on this website. Thanks !!