I dont use my sizzix with raw polymer clay, because you just end up
squishing the polymer clay from the pressure of the sizzix machine. Besides
it will stick to the foam under the dies and in the dies, and on the metal
blade inside. I don't recommend wasting money on it to play with raw clay.
I do use it however for allready baked sheets of clay for shapes, etc..
works really well.. although I know that sizzix does not recommend its use
for clay, and will probably void the warranty on your machine and dies if
they knew what you were using it for (blah blah blah).
However I'm sure there might be a way to modify the dies (remove the foam
core, and drill a hole through the top to be able to "push" the clay out of
the die once cut) But then again with the cost of the sizzix dies, I think
that you would be better off cutting paper templates and hand cutting raw
clay yourself by hand then reverse engineering the die itself to be used