I usually TIG weld my frames together but I have been practicing the torch brazing quite a bit. I still am not great but I have the concept down. I have done a few seat tube collars and also fillet brazed some bridges and canti bosses that were pretty good. Not great but OK.
I collect vintage bikes also and really like the British racers of the 30's on up. I started thinking about making the lauterwasser handlebars, headclip stem and plate crown fork, I knew i wanted to include a goose-neck style seat pillar and a "hand hewn" look that I love about those bikes. I figured I may be able to find some old cast lugs or take apart an old frame but I decided to make some lugs with the geometry I wanted for this project with 650B wheels and 68 seat angle. I also wanted it to be light and use materials in an efficient manner. I wanted a young wolf in an old wolf's clothing. I love riding the Zona tubes and have a 7/5/7 kit chillin' on the shelf
One of the latest things I thought about was the steering head platform. I have a head tube cutter for 1" and thought about doing that. While digging around for parts for this rig I found a couple of "Italian" type BMX 1-1/8" headtubes with integrated cups. I don't really like this system but I thought it would be cool to use make lugs out of the ends of one of those and slip a smaller tube inside to look a bit slimmer than the fat 1-1/8 head lugs. (1-3/8" fits inside perfect)
I am also planning to use Paragon track type dropouts (In case I end up fixed/flip flop) . For the chainstays, I am thinking of using the zona chainstays after I have re-drawn them back to tapered-round on the front end if they will go without splitting.
I started machining the lug sleeves a while ago. I used 4130. 1018-1020 would have been a better choice.
OK, so here is my question. How will it go if I try to lug braze the pieces I have here and fillet braze the lug joint? I am thing about doing it all during one "heat" but deep brazing the sleeves and switching torches and doing the fillet?
I really don't want to TIG steel in the lug joint and file it all out to make it look like a lug.
Here is what I made yesterday.
29 360 by frankthewelder, on Flickr
29 361 by frankthewelder, on Flickr