I need to flatten some lengths of copper tube for a project, and haven't figured out the best way to do it. I want to start with some 3/8 or 1/2" copper tube (in 3 or 4 foot lengths), flatten it to into an oval/ellipse that's about half the original diameter, and then braze or solder it to the rest of the radiator/heat exchanger. Anybody done this before? I need to make a few of these, so I thought about having some dies made for a Pexto-type bead roller--maybe make two sets, one to go halfway, then another to finish it? I'd like to do this with a hand-crank machine, but maybe I'll need hydraulics? If anybody has pics or links of something they've made or bought, I'd love to see it.
A bead type roller will curl it. If you are only doing a one time deal go to a local fab shop and let them hit it in a press brake with flattening dies. I can't imagine it would cost very much.
The success of the flattening will depend on the type of tubing you start with. Unless you use some 'dead-soft' material you may find that the tube will develop some cracks on the new very-short radius. I would suggest talking with someone in a copper supply company for recommendations. http://www.copper.org/applications/plumbing/techref/cth/cth_1stand_type.html .
Great--thanks guys. I hadn't even thought of it stick-at-a-time in a press brake. I need to do a bit of this so I'd hunt around to find some dead-soft stock...