Making mold of a soft head figure.

Posted in Custom Workstation

Hi, this is SRG I am new to the board. I ran in to a problem. I went to cast a Heman type figure head. You know the soft head figures ( hollow on the inside ). I put in the neck peg and was going to mold it as one solid piece as a hard head. Now her comes the problem. the Silicone I use is Mold Max 15-T from Smooth-on. I have to pressure the pot to about 40lb of pressure then bring the temp up to 200 degrees. When I did this the peg was sucked up to the head leaving no room to mount the figure to the body, and it also squashed the head. Making the face look like it had been squeezed. I understand what happen, but do not know what to do to fix the problem. Do I fill the head with something so it does not depressureized ?? Maybe someone else has come across this before and have come up with a solution. I do not want to do anything to destroy the org. part. Please HELP !!!!