Moldstar 15 problems! Bad batch of silicone?

[Kylash]

so I've been using smooth On moldstar 15 for a while now, but recently I got a trial sie batch that is giving me a lot of problems and I'm not sure it's the silicone or not. everything cures reptile where it touches the piece being molded. Now I know this usually means the paint or surface of the piece has sulfur in it or something else inhibiting the silicone from curing.

I've tried at least 5 different paints, acrylic sealer, enamel, model master primer, tamiya spray, etc, and nothing is working. Ive even used paint that has worked fine on prototypes for molding before. has anyone had this happen recently, is the silicone defective? like I said everything around the piece cures, but the surface touching the prototype doesn't cure at all and is nearly liquid after 8 hours.

Net I'm going to try a small surface that is unpainted to see if it is just be paint and if so, I'll have to find me that it doesn't react to.

 

[Yodajammies]

It could be the base material you're molding against. I've had silicone inhibition issues from a urethane tooling board even when it was epoxy coated, sealed, painted, and hosed with mold release.

Or it could be the paint - I might try just a standard acrylic clear coat and then force cure it in an oven at low temp for a couple hours just to make sure everything is on the up and up.

Or you could have a bad batch of silicone. These things happen from time to time.