Contaminated silicone due to contaminated thinner?

Christina Whiting

Hi all,
  I’m going to ask one of those age old questions you hear again and again in different forms.  Once a platinum silicone cast has been contaminated by thinner during patching, how do you move forward? I have stripped contaminated layers, applied a thin coat of silpoxy and then continued, only to find contamination again.  

Some background info
cast poured in Eco 10, several months old.  All new silicone and thinner purchased and used.  Patch work done with silpoxy base coat and psycho paint on top since the cast is too old for eco to stick to properly.  

Thanks so much for any help.  I’ve watched all silicone patching tutorials and have been molding and pouring for a bit under 5 years.  There must be a way to save to the cast. 

Chris Ellerby

Contamination can be tricky.  Sometimes surfaces can be cleaned with solvents if you need to go back and apply more silicone, but once you have a contaminated surface all bets are off.  Sometimes you can make it work, other times you just end up fighting it.  My own results with contamination have been so mixed that I can't really say any one thing that did or did not work.

Anyone else have success recovering post-contamination with platinum silicones?

/Chris