Cambering aluminum angle 1

[kennewton]

Would like to uniformly camber a 3"x3"x.25", 10 foot aluminum angle the hard way (flange in). Camber height would be 5% of the cord 6". Material grade to be determined. Need 5 pieces.
How could this camber be formed without heavy equipment? For starters, two lengths may have to be clamped back to back, while forming, to minimize off plain curves. Suggestions and comments appreciated.

 

[berkshire]

kennewton,
Find a guy with a Buffalo roller and give him the job.
B.E.

 

[Ron]

Agree with Berkshire. Don't try to do it with heat, as you might for steel. Aluminum gets all screwy in strength when you heat it.

I would probably not use a terminal heat alloy (for instance, T6 in 6061 or 6063). I would use a lower treatment such as a T4 or T5, to cut down the potential for cracking. You can always treat later for strength.

 

[kennewton]

Don't know anyone in the area with a roller. Was considering a press and multipule small bends every few inches. Not shure how to do this without twisting or off plain bends.

 

[MikeHalloran]

For angle half that size and half that thickness, you could use a metal shrinker or a ring roller, both of which you can buy at Harbor Freight.
... you might buy them, or download and study the manuals, just as a learning experience.

For angle in your size, you really need a three-ring roller, a fairly big one. Nobody gives them away. Even used ones in decent shape can be expensive. Ask your local used machinery dealer.

Incremental bends in a press brake will require that you fabricate some kind of slotted fixture to support the flange, and even with an experienced operator, the result is not going to be pretty.

Luckily, you don't need extreme curvature, so you might be able to clamp one flange to a steel table, and induce the curvature by beating sideways on the free flange with a block of steel and a big hammer. Make a checking template from plywood to guide you. Work out the technique on a piece of smaller angle first.

If your labor is worth anything, it will be cheaper to buy the ring roller, even a new one...


If you can't find anyone local who routinely bends AL angles and such, you may be able to flush one out, somewhere, by making a sketch and putting it up for bid on mfg.com.



Mike Halloran
Pembroke Pines, FL, USA

 

[berkshire]

kennewton
The other thing you might look at for this job is stretch forming the parts. This is not something you can do in house, but for a person with a stretch forming machine, the tooling can be simple, even crude, a couple of 3/4" plywood plates cut to the curve you need can suffice.
Try stretch form USA inc or if you insist on rolling them this company has several plants in the USA , one of them may be near you.

http://angleiron.net/Augusta

B.E.