Bending aluminum plate

No experience, but my intuition matches yours.

The allowable bend radius for a particular alloy & temper is a multiple of the thickness, and IIRC you can get that multiple out of handbooks -- have you looked?

No experience, but my intuition matches yours.

The allowable bend radius for a particular alloy & temper is a multiple of the thickness, and IIRC you can get that multiple out of handbooks -- have you looked?

No experience, but my intuition matches yours.

The allowable bend radius for a particular alloy & temper is a multiple of the thickness, and IIRC you can get that multiple out of handbooks -- have you looked?

Bob Engelhardt fired this volley in news: snipped-for-privacy@news6.newsguy.com:

Use radius noses on the brake.

Lloyd

If you have enough extra, make test bends on narrow strips. Pay attention to matching the direction as some aluminum shows "grain" from rolling.

I hope you have a big press brake. The Chinese 3-in-1 has trouble bending 1/16" 6061.

jsw

If you know the alloy and temper:

A workaround is building up the radius from several strips of thin stock. It's clumsy and imprecise but works with the existing male dies. jsw

With mystery meta. "Youse pays yers nickle youse takes yer chances!"

Probably going to need a pretty healthy radius of bend for 3/16 anyway.

I have heated 5052 and let it sag to a from, but its really touchy. To much heat and you get a puddle quick. 5052 is a bad example though because it forms really well with bending equipment.

Some types of sheet really only like to bend in one direction. They break if you bend them the other way.

If you have need for aluminum that can be heated to sag into a form, look into the "superplastic" special aluminum alloys. That's what they're made for. Typically they use some vacuum or some positive air pressure, but it doesn't take much when you get them heated into the plastic range.

They may be hard to get in small quantities, but a good supplier may be able to get it.

This is the link I intended:

Weird. I only hit "send" once. Really!

If it is 6061 T6 you are going to want to anneal it first - it will age back to close to T6 in about 3 months.. Vover it in soot, heat till the soot burns off and quench.

Then it will bend like butta. (sorta)

I have a bunch of 7075 probably T6... It seems to be unbendable. Will this trick work on this alloy?

As Bob says, if you know the alloy you can look it up. If you don't know the alloy my first guess would be 6061t6 (highest sales volume for general fabrication) unless you have access to aerospace scrap in which case it might be 7075. The minimum bend radius for 6061t6 is about 3-4 times the thickness, so if that is ok just go with it. If you need tighter, anneal it and the minimum radius goes down to about the thickness. If you are lucky it is 5052 and the minimum radius is 1-1.5 times the thickness already, but it's only going to be 5052 if whoever originally bought it planned to bend it. If you can, cut a test strip and play with it in the press brake.

If it is 6061 T6 you are going to want to anneal it first - it will age back to close to T6 in about 3 months.. Vover it in soot, heat till the soot burns off and quench.

Then it will bend like butta. (sorta)

Clever. Certainly the expedient approach for 1 or 2 bends.

Thanks, Bob

On 8/7/2013 3:37 PM, Jim Wilkins wrote: ...

It's a 20T HF "H" press with home made dies. We'll see.

I don't know the alloy. What's worse is that I don't have any experience with known alloys, so I can't even guess at what it might be.

Bob

That's interesting even without knowing the alloy & temper. It shows that for all alloys, only the highest temper requires 3x or more radius.

Bob

OK - the covering with soot is doable (micro Ox-Acet torch), but the heating part: how much heat do I need? I'd guess that 3/16 aluminum is going to conduct heat away really fast. Can it be done a little at a time?

Bob