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matt matt is offline
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Default Bending 1" X 1/8" aluminum bar

On Dec 25, 1:40*pm, 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!


The suggestions that have been made already are pretty much in the
ballpark, but the job you are describing really isn't very clear to
me. Is the angle you are bending a.) 35 degrees from the straight-line
bar condition, or b.) a 35 degree included angle for the bend? If I
were doing a.), I would clamp the short end in the vise, and take
advantage of added leverage of more material sticking out. Be aware
also that you cannot create a zero-radius bend with sharp corners,
even in the commonly available hardware store aluminum strip which I'm
guessing you are using. Too tight a radius will lead to cracking and
failure, either during your process or later while in use.
I have often done this kind of thing using a standard V-block (90
degree V, some kind of stupid import grade is fine, obviously) as the
bottom die, then cobble something together maybe with a mason's chisel
or some other kind of at-hand tool to adapt for a top die, and a
couple of hours later, you have a custom press brake. It's much easier
to do if you have a hydraulic press, or even a good-sized arbor press.
A 3-ton arbor press is a fine thing to have around for small sheet
metal forming work, as long as you can set it up with your own home-
made dies. A 12 or 20-ton hydraulic H-frame press gives you a little
more ability and working room.