Luckily the process went pretty smooth thanks to this book that really taught me everything there is to know about mold making
I chose to use Lego pieces for the containing walls instead of clamps and wood.
So here's the first photo. The head is made of polymer clay resting on plasticine and sprayed with PAM oil (the "extra virgin" is not required! It's what I had in my kitchen...)
Second head...... looking worried! LOL
Third photo: the plaster has set and I removed plasticine and part of the wall, now I'm ready for pouring the second part (and I'll need to re-build the wall and re-spray with Pam)
It took a good 24 hours despite resting under the fan and the AC on.
5th photo: My first porcelain pouring went well
and here are the green pieces that I roughly cleaned and are drying for a first soft firing in the kiln.
If you want to get into mold making, I strongly recommend the book I suggested above.
I bought other books before this but none of them helped me out as much.
This is specific for doll makers. Most other books will teach you how to make molds for pots and cups which is about the same thing but you really get the hang of it when you see another doll maker doing it.
I'll never be a fond mold maker but now I know I can do it.... :-)