making sphere shapes in sheet metel?? I'm new....

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grinch
Posts: 2
Joined: Sun Dec 19, 2004 2:08 pm

making sphere shapes in sheet metel?? I'm new....

Post by grinch »

I'm New to sheet metal stuff or should I say I've never done any of it but am wanting to make some sheet metal 1/2 spheres. I'm thinking the diameter will be just under 1.5in. I'm looking for the end result to be about .093in thick.

I'm wondering if anyone makes off the shelf dies and if so can I do this at home with a press.

I'd like to do this for a resonablr price if possible

Thanks
Grinch
D_R
Posts: 297
Joined: Mon Feb 03, 2003 6:44 pm

Re: making sphere shapes in sheet metel?? I'm new....

Post by D_R »

If you've got some machinery you may get some ideas on how to make your own dies at http://www.bonnydoonengineering.com

They sell dies for use in small presses. I don't think they'll have the size you need or even one with the clearance for .093 material, but you can see how they do their's.

Other than Bonny Doon it's unlikely anyone sells off the shelf dies of this type. The variety of applications would be too great for anyone to carry all styles.

Depending on material, press tonnage may be an issue. It's hard to calculate the exact amount needed, you can easily calculate the absolute maximum that would be needed though. The max tonnage would be equal to the tons needed to shear the same size part. max tons=tensile strength*thickness*length of cut

In your case for mild steel 50,000*.093*3.14*1.5=roughly 11 tons. That's the max possible, so figure, maybe, half that or around 5 tons.
joel_k

Re: making sphere shapes in sheet metel?? I'm new.

Post by joel_k »

If you have a lathe, or even a rigged up turning spindle, you might be able to spin the spheres. Process roughly involves taking flat sheet and working it with a tool over a form as it spins. See the following link for more info:

http://www.chaski.com/ubb/showflat.php? ... o=&fpart=1
Ries
Posts: 208
Joined: Thu Mar 25, 2004 11:05 pm

Re: making sphere shapes in sheet metel?? I'm new.

Post by Ries »

You could press em, using a big ball bearing for the male die, and a sheet of 1/4" or 3/8" plate with an oversize hole cut in it for a bottom die. Or use urethane like the bonnie doon guys do.
12 ga is heavier than you think- takes a fair amount of tonnage. Just to punch a hole that size takes at least 10 tons.
But why not just buy em-
http://www.wagnercompanies.com/ends/balls.html
A little thicker than you want, but cheap and easy.
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