Something I haven’t really found any info about is if there’s any difference in heat affected zone between lugged brazing and fillet brazing.
Can any type of tubing be used for either technique? Are there specific tubesets for one vs. the other? Is there a difference in heat affected zone between small fillets and large fillets?
If I’m gonna have to get a proper oxy propane torch anyway I’d be interested in exploring both techniques and their pros and cons.
I’m pretty sure there was an article covering this in an older BikeTech publication. I’ll see if I can locate it.
Hananas,
If you haven’t done so already, check out Doug Fattic’s posts on Velocipede Salon in regard to Oxy/Propane temperature.
Joint/material failure isn’t just about how hot a tube gets or how far the HAZ extends visibly. It also has to do with how long a joint/material remains at temperature. As a newer builder you might risk “slow roasting” a fillet brazed joint with Oxy/P and end up with a cracked frame and missing teeth.
I don’t want to discourage you, I just mean to say that there’s a bunch of additional complexity to consider.
Alright so as a new guy it would be safer to stick to lugs and silver if I’m not getting acetylene?
You can do either with oxy propane, you just need to practice more to build a fillet brazed frame that won’t break than you do for silver brazed lugs that won’t break, no matter the fuel type. I think you will need to post pictures of some practice joints if you want a more informed opinion than that.
Alright I’ll definitely post some photos, maybe also videos if I can when I start practicing with the proper setup!
It’ll take a couple months tho because I’m saving up for the setup and can only set aside so much each month. Saving up to buy a house is still financial priority no. 1…
Hananas,
I’ve said this in other areas and I’ll repeat it here not to discourage but to make sure you’re aware:
There is always the cost of tuition. You will either pay that by hiring an instructor or by making lots of mistakes and using more materials. They both have pros + cons.
If I were to do it over, I’d actively try to supplement online research + feedback with a few real-world tutorials. Literally, “Hey, can I pay you $100/hour for a brazing lesson?” If you spend $300 in education you’ll save at least $600 in your time and wasted materials.
I would really love to, but I’m having a very hard time finding a teacher I can get to. (Flanders, Belgium or more specifically near Ghent or with a good train connection to Ghent)
Best I’ve found so far is LaFraise in Roubaix but the price for the course just kinda scares me. (Edit: and I see they’re fully booked until 6/2026)
I’ll try contacting the only traditional framebuilder I know of that’s somewhat easy to get to, L’Ecurie in Brussels, maybe I can pay them for some lessons.
I also have contact info for the guy that owned the bike shop that built my Columbus SLX frame in the late '80s in a town nearby, maybe he still knows a guy but it’s a long shot.
Thanks! I found links to them also here on the forum, will be reading through those, and probably all of them.
When I learned TIG welding my first lessons were with someone who built roll cages and repaired panels on cars (roll cage tubing is about 45mm x 2.0mm – other than it being round, it’s not really like bike tubes). It was a start, better than YouTube University, and faster than going to my local college and taking a semester course on welding when all I really cared about was bikes.
I mention this as an encouragement to look outside of the box for solutions. If I were doing this now with minimal accessibility to true frame-building schools, I’d be calling motorcycle fab shops, coach craft biz, etc and seeing if there’s anything I can trade for a few hours of instruction. In my mind, 3-4 hours of broom time is worth 1 hour of 1x1 torch time.
As a bonus, you’ll probably pick up skills that are meaningless now but will pay dividends in a few years.
Oh absolutely!
I’ll continue to look around, I’m busy with other stuff at the moment but definitely not giving up on it.
Check out this thread!
