bending metal tubing

[davy B]

so im planning on building a concept bicycle from scratch and in my drawings the seat-stays are going to arc down like most cruiser frames do, i talked to my dad and he told me that he sold our metal bender several months ago, so as of now i dont have to many ideas.

do any of you have clever ways of bending metal tubing you would like to share? any help would be greatly appreciated, Thanks!

 

[Rockit!]

The old school trick is to ram sand into the tube and weld a cap on it....It keeps the tube from collapsing as you bend it.

 

[DougC]

The other way to bend [round] tubing without it kinking is to bend it around a pulley that has a groove that is the same OD as the tube. Conduit benders use this principle, and hardware stores sell them pretty cheap. Those will work up to an inch or so.

Another easy option if you have larger-diameter thin-wall tubing to bend--like, 2 or 3-inch diameter, the easiest way is to phone around to a cheap muffler shop and ask if you can bring it by at the end of the day and have them bend it for you for $20 or whatever. The bends tend to be rather tight and wrinkled, but at least they won't be kinked and are still strong.

 

[Sinner4]

It all depends on the old school way of bending, sand works inside the tube. I have bent 1 and 1.5 inch between 2 large branches in a tree, not to tight but it worked.. For some short stuff, one end on my step and me at 230# in the middle and stood till Ibent it the way I wanted. Now I need to get my lazy butt down to harbor freight get their tubing roller and go to work.