Hmmmmm, I don't have Autocad so couldn't see the design.
I have a beautifull nut cracker I got way back in 1974, and it's shaped like a small fly press, or actually like a horseshoe with a bottom anvil....the screw is in the top.
The body is made from die cast Zinc, and plated with a satin Nickel finish.
It cracks any nuts known to Man, progressively and without shattering the kernel, and will handle Wallnuts too...Brazils are a breeze.
Before I got the press I tried to use a lathe drive carrier....(anyone turning a job between centres will have one of these), and it worked after a fashion, provided you picked the pieces up as they tend to go in all directions.
I have resorted to a pair of vice grips, but after getting the skin on my finger nipped between the side of the jaws....chucked it.
Wear glasses if'n you are tempted to use a toffee hammer, as Wallnuts are lethal projectiles, and Hazels are finger nippers.