In article , "Steve W."
wrote:

Tim Wescott wrote:
On Tue, 25 Dec 2007 12:40:10 -0800, rgoldner wrote:

I have to put 35° bends in 1" X 1/8" aluminum. I tried a vice and
hammering the end of the bar that sticks out about 1". This looked real
bad and if I bent the aluminum too much and tried to straiten it a
little it broke. Obviously, I don't have a metal brake. Is there a
better way to do this? I have to make eight bends. I do have a CNC mill
and a lathe as well as tooling and other assorted equipment.

Thanks!

You could make a little mandrel with a "V" groove anvil and matching
punch, suitable rounded. Put the part on the anvil, and press the punch
into the part with a hydraulic press. Plan on playing with springback a
bit to get the angle just right.

The "trying to bend it back makes it break" worries me -- you may be able
to control this with the radius on your punch, but you may just be using
the wrong alloy of aluminum. I'd check on the alloy, to make sure it's
kosher to bend it.


If you have a GOOD vice make up a small set of jaws that will act like
a brake. Just use a couple pieces of angle to form the jaws. HF used to
carry something like this. Then mark the bend location and start
bending. Make a bend template out of cardboard or sheet metal so you can
pull the part and check it easily.

IIRC, aluminum bends best cold - dry ice cold

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