Posted by Joe Lorenzino [216.197.153.67] on Monday, March 11, 2013 at 21:31:24 :
In Reply to: Metalurgy question posted by Tim Holloway [69.54.28.229] on Monday, March 11, 2013 at 19:13:23 :
When working copper, we were tought to heat it up until the torch flame (using propane/MAAP gas) turned orange around the edges of the piece, then quench quickly in cold water. On steel, this treatment would make it hard and brittle, but leaves the copper dead soft.
At one of the shops I used to work at we had some sort of low temperature alloy that you could melt with boiling water. We used to cast it inide of thinwall tubing, form the bend, then melt it back out again. It works Very Well.
If you only have the one bend to do, maybe just slide a solid bar of aluminum or something insde the copper, bend it, and just leave the suppoert bar insde.
You might be able to do a nice bend using one of the benders the electricians use for conduit. Have used their Greenlee power benders for this sort of thing in the past. Conduit benders are usually a "draw" type rather than a "compression" type bender, and so are less prone to deform the material the way a muffler machine does.
Follow Ups: