On Sat, 8 Oct 2011 23:50:36 -0700, "anorton"
wrote:


"Steve B" wrote in message
. ..
I have some 3/8" copper tubing that I need to bend at a tight radius. Like
2". I have the spiral bender, and another hand held type, but can't find
either. Next week, I gotta get organized. In the meantime what's the best
way to bend it? I've heard of putting it full of sand. If I do that, do I
bend it around something round, or just bend it slowly and cautiously?

Steve

I have tried the sand method and it did not work well for me. The classic
way to make the sharp bends on trumpets and such is to fill the pipe with
melted pitch and let cool. Another method is to fill with a water-detergent
mixture and freeze it. The detergent keeps the ice from becoming hard enough
to burst the pipe. Don't ask me what the right detergent concentration might
be.
Instead of sand I read about brown sugar used for bending. I tried it
and it worked well. Hard to get it into the 1/4 OD tubing though. It
took a really long time pounding it in with a 1/8 dia rod. But removal
was easy, just soaked in warm water.
Eric