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Anybody here have press brake experience? I was to start with 3x3x.375
6061-T6 aluminum Tee extrusion, 4 inches long, and bend up the top of
the Tee on each side 30 degrees. So the part will then have a Y shape.
Can 6061-T6 be bent that much without cracking? And how much tonnage
should the press be to do this work?
Thanks,
Eric
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For flat sheet the minimum inside bend radius for 6061 is roughly equal to
the thickness for a 90 deg bend, without annealing, but for .375" thick
material I'd probably try to keep the inside radius at 0.5" or more, just
for safety. Nothing worse than bending a radius that you knew was too
tight, seeing some small surface cracking, telling yourself "it'll be fine,
I can barely see that", and then coming back the next day and seeing the
cracks go half way through :-). It also matters whether you are going with
the grain or perpendicular to it; with the grain is better. You will be
going with the grain and only going 30 deg so you might be able to get a bit
tighter than 0.375" inside radius. I assume you will make a die with a deep
slot to accommodate the bottom leg, and come down from the top on center
with the punch to basically make both bends at once, just like it was a
single bend in flat stock? I did a quick google search for bend force
calculators, and http://www.custompartnet.com/calculator/v-bending-force was
about the first hit and says you will need 6-12 tons to make the bend.

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Regards,
Carl Ijames