Learning to braze

[BevanTaylor]

A couple of my current and recent projects to practice my oxy-acetylene brazing. I'm building a balance bike for my son, hopefully it will be done by the time he learns to walk! Future frames will probably benefit from some less sketchy fixturing, but I'm trying not to spend too much money until I'm working again.
At the other end of the size spectrum, I made a drain grate cover for the guy who owns the shop space I'm borrowing, it's strong enough to hold up my car so I'll call that a success.
Lastly, a little decoration, which will be part of a mobile I'm making for my cousin's new baby.
I'd be interested to know if anyone has any tips on bending round tubing, I'm using .065" wall cold rolled steel, but I'll move on to chromoly at some point when I can find a good source for that.

-Bevan

 

[John Conroy]

Cool, I haven't brazed anything in years. I live in the Edmonton area too so if you need access to lathe, mill, mig or tig welder give me a shout.

 

[BevanTaylor]

Cool, I haven't brazed anything in years. I live in the Edmonton area too so if you need access to lathe, mill, mig or tig welder give me a shout.

Thanks, I may just take you up on that! I've been coping my tubes with my angle grinder, but it's a bit tricky to do, a mill and a hole saw is the way to do it correctly, I think.

I'll add some photos of the finished products next week, hopefully, though the wheels for the bike won't get in until mid March.

 

[DPittman]

Well it looks like you've got brazing figured out. Do you have access to mig weld? Brazing can get expensive with bigger projects. Of course for copper or dissimilar metals it's great. I always love doing a good brazing fix job.

 

[DPittman]

Soft soldering is also a choice for straight copper joins especially decorative stuff

 

[BevanTaylor]

Well it looks like you've got brazing figured out. Do you have access to mig weld? Brazing can get expensive with bigger projects. Of course for copper or dissimilar metals it's great. I always love doing a good brazing fix job.

No, I don’t have one. Eventually I want to learn to tig, and I read that starting with gas welding is a good way to get the technique figured out without spending an arm and a leg on equipment. The I got watching Paul Brodie’s “framebuilding 101” YouTube series, where he does a bunch of fillet brazed bikes, so that’s what I’m practicing to try to do next. I brazed the drain cover because I couldn’t get enough heat into that thick plate to weld it, even after I bought a bigger tip. If I end up doing more heavy-ish stuff like that I will try to buy a mig or maybe a tig/stick machine.
One of the next things I’ll get is some sliver solder, but there are so many types I don’t really know what I should buy!

 

[DPittman]

No, I don’t have one. Eventually I want to learn to tig, and I read that starting with gas welding is a good way to get the technique figured out without spending an arm and a leg on equipment. The I got watching Paul Brodie’s “framebuilding 101” YouTube series, where he does a bunch of fillet brazed bikes, so that’s what I’m practicing to try to do next. I brazed the drain cover because I couldn’t get enough heat into that thick plate to weld it, even after I bought a bigger tip. If I end up doing more heavy-ish stuff like that I will try to buy a mig or maybe a tig/stick machine.
One of the next things I’ll get is some sliver solder, but there are so many types I don’t really know what I should buy!

I do a bit of silver soldering and I wasn't sure exactly what to buy either but ended up and buying some 45% silver (1/16" wire) and white soldering paste. It seems to work. Knowing how to braze will help with silver soldering techniques a bit.

 

[BevanTaylor]

I'll pick some up next time I go by my local welding supply; next part of the balance bike will be the forks, and I think my design will work best with some silver solder rather than trying to get bronze to wick between two fairly tight tubes.

 

[DPittman]

I'll pick some up next time I go by my local welding supply; next part of the balance bike will be the forks, and I think my design will work best with some silver solder rather than trying to get bronze to wick between two fairly tight tubes.

If you don't know yet....silver soldering is really expensive. I think I maybe paid around $45/ounce.

 

[BevanTaylor]

If you don't know yet....silver soldering is really expensive. I think I maybe paid around $45/ounce.

Yea that’s pretty steep. What I have seen about it is that the stuff goes a long way. I suppose I could also fusion weld the joint I need to make, it’s not likely that he’s going to break it either way.

 

[DPittman]

Yea that’s pretty steep. What I have seen about it is that the stuff goes a long way. I suppose I could also fusion weld the joint I need to make, it’s not likely that he’s going to break it either way.

Yes it does go a really really long way. I've only done small intricate joins with it but it only takes a teeny weeny bit for them.

 

[BevanTaylor]

A couple updates to the balance bike project. I built a quick jig to attach the “chainstays”, and picked up some new files which improved my copes quite a bit.
I made a fusion weld on the bottom of the steerer tube to attach it to what will be the centre part of the fork; this also gives me a nice lip on the other side for the headset bushing to ride on.
my first attempt at a fork didn’t work out perfectly, I’ll post the second attempt when it’s completed later this week.
another time I would buy smaller tubing for most of the frame, this stuff is .875 OD and it has a slightly beefier look than I would have preferred.