Forming compound curves in heavy aluminum plate

[Bigfoot1]

BillyDoc
Your experiment that gave you a value of 6000 pounds to design an English wheel is incorrect.
The English Wheel works on the principle of producing very small local stresses
in an extremely small area to, ( I hate to introduce a new term) micro deform
sections of plate to produce a curve.

Some theory.

If you have 100 pounds acting on 1 square inch, the stress 100 psi, then if you reduce the area to one half inch, then the stress becomes 200 pounds per square in. ( or 100 pounds per 1/2 square inch) and so on

When you put a cylinder or a sphere and lay it on a plate, the contact area is theoretically infinitely small as only the outer most part contacts the plate.
In a cylinder, there would be an infinitely small line and the sphere, there would be a point.

Lets work with the Sphere

You put a load of 10 pounds on the sphere and the area is infinitely small. The plate underneath, deforms a bit and say that the contact area is .001 square inches
So the load is now 10 pounds divided by .001 square inches or 10,000 pounds per square inch.

So when you run a plate through an English wheel, with very small loads, in pounds, you can get extremely large stresses, in pounds per square inch.
And the deformation is done on a very very small localized area.

In summary, what you did the test on does have any bearing on the loading that it will take to build an English wheel
Cheers

[Guy Brown]

I have just posted my English Wheel for sale. See the Marketplace.
Thanks
Guy

[Stumble]

Billy,

Instead of messing around with this yourself you might want to think of calling Trinity Marine in Pascagoula (i think, near there at least). They make aluminium superyachts and I know they are really slow in the yard right now. They just might be willing to give you access to the yard for an afternoon to bend what you need, or at least tell you where they get it done at.