wrote in message
...
On Wed, 18 Feb 2009 02:59:41 GMT, John Forrest Tomlinson
wrote:

On Tue, 17 Feb 2009 21:48:28 -0500, "Ed Huntress"
wrote:


"John Forrest Tomlinson" wrote in message
...
I'm trying to make something like this:

http://sports.webshots.com/photo/121...44194919ClRBmi
http://sports.webshots.com/photo/121...44194919EvrnCe

and am not sure what sort of aluminum to use. The person who made
that descibers it as:

"I carefully and gradually bent them over my thigh. The material is
1/4" x 1.5" aluminum that I bought at a hardware store and the bases
are just two layers of 3/4" plywood laminated together. When I bent
them, I just eyeballed the curves and left the ends longer than I
needed, so I could adjust the shape."

I have the choice of buying 2024-T4 or 6061 T6 -- will either of these
work? What would be more durable?

Thanks in advance for any advice.

JT

2024 is roughly twice as strong as 6061, but it doesn't bend well. Just
eyeballing that job, I wouldn't trust 2024 for the application.

Either one is probably a lot stronger than you need. By the looks of the
other photos, the task is limited more by spring flexure than by
strength.
And the springiness (Young's modulus) of both grades of aluminum is the
same.

BTW, bending even 6061 over your thigh may give you more trouble than you
think. Whatever that guy bought at a hardware store was not likely to be
either 6061 or 2024. It probably was 5052 or 3003, or maybe even one of
the
1100-series grades. All of them are a lot weaker than 6061.

Thanks! That's exactly the info I was looking for.

JT

It's generally called "utility grade" or possibly "architectural"
aluminum. Non weldable(generally) and not heat treatable

The decorative and architectural grades are often specialty grades in the
1000 series. They're very corrosion-resistant, bright, and relatively weak,
and they're often chosen for their extrudability (1050, 1060, 1100, rarely
1350, and custom alloys made for extrusion).

But you never know what you're getting in a hardware store. If it's 1100, it
is easily weldable. The same is true with 1060, if that's what you have.
Some of the custom architectural alloys can be more difficult.

--
Ed Huntress