Katie, No hazards. But, you can not cast anything that is undercut.
It does and excellent job on anything you can “lift” out of the clay.
You can duplicate someone’s sand dollar earring in excellent detail
in about 5 min start to finish. The video will simplify the casting
for you. I bought mine long before Rio started carrying it so I
don’t know if it is the same video. Your idea for prototypes is
great within the ‘undercut’ limits of clay casting. Good luck,