u/0r10z

Hi fellow mold makers, I have a very technical question. I am trying to make a mold of a very intricate high detail and deep crevice flower. I used dental die cast cement type IV to make a master and I sealed with clear acrylic spray. I am using A15 platinum silicone to make the mold in a 3D printed molding. The piece is large enough to require multiple demolding cuts. In order to make the silicone softer I added silicone fluid (8%) but end result was A8 hardness and still too hard to use if I am making many copies using same mold. I also use vibrating plate to pour slow so no issues with bubbles. Here list the list of issues:

1. Mold is too hard need A5 but true A5 is $250 and is too expensive
2. Silicon fluid collected at the top of mold in one spot and in deep crevices even though I mixed well and degassed in vacuum preventing hardening and ruining the mold and die cast.
3. How to effectively make demoldong cuts clean at an angle so that liquid does not escape from the mold when used.
4. Any suggestions to improve my process am I missing steps?

Anyone had a chance to review? Looking to buy as emergency go to device but have no experience with plastic elements. Do they break down quickly in high radiation environments?