Best place to source scrap tubing to practice brazing

[AnthonyLubetski]

Well, I have a long winter ahead of me and I want to try my hand at frame building. I have some experience with O/A welding, but I don't want to jump into building a frame without brazing a couple (hundred) joints first.

Where do you guys inexpensively source your scrap tubing for practice? Should I just cut up an old bike frame?

[David Tollefson]

Aircraft Spruce has grab-bag tubing ends that you can buy on the cheap.

[Doug Fattic]

What kind of brazing practice do you want to do? My suggestion would be to buy 4130 steel tubing from Aircraft Spruce or Wicks in 0.035” wall thickness (about .9mm). It costs less than $4 a foot. Get 1” and 1 1/4” OD and maybe some smaller sizes as well just to get started. It is way too much bother to cut apart an old frame and clean off the paint and rust. And tubing on a cheap frame is probably too thick anyway.

My suggestion would be to use a 2’ long piece of 1 1/4” OD tubing as a base. Use short (maybe 30mm) 1” OD stubs mitered to fit the 1 1/4” tube. The advantage of using a long tube as a base is that it can be moved around to put the joint in the ideal position while brazing the short stub to it. Then multiple short stubs can be brazed onto the end of the long piece.

Doug Fattic
Niles, Michigan

[buildyourown]

I bought a grab bag from Aircraft Spruce when I started my latest cargo bike. I figured I was going to be doing enough weird stuff shooting from the hip that having large selection of drops would be nice. They send you a lot, but most of the sizes and wall thicknesses aren't bicycle appropriate. Good to have around but your are better off just buying a stick of whatever is cheap.

You also dont need to do hundreds of joints. I did maybe 5 and felt very confident in my ability to get a good fillet braze. You'll be amazed how much you can improve joint to joint after you cut them apart and see the issues.

[e-RICHIE]

http://www.velocipedesalon.com/forum...rum-36866.html

[waterlaz]

Usually you can get a broken non-butted frame for free (if you don't have one already) and just cut it into A LOT of practice tubing.