Morgans wrote:
"J.Kahn" wrote in message
.. .
I need to make bends of about 30 degrees in a 3/4 x .049 longeron tube,
with a tight bend radius, no more than 3 inches. Can I do the bend hot
without wrinkling the tube by free bending or do I need a supporting die of
some kind? Anybody have any specific techniques?

Good luck, without a die bender.

I have heard of some people bending tube by packing it, very tight, with
sand. I have never done it, personally.

We're only talking 30 degrees here guys. Sheesh!

Mark on either side of your 30 degrees. Heat the inside of the bend in
the area between the marks to a dull red, then each of you grab a side
and bend it into the hot area as if you were back peddling a canoe.
Don't add a lot of pressure. You're just "assisting" the torch heat.
Let it cool completely, and do it again if you don't have enough bend.