aulrich Posted February 9, 2015 Report Share Posted February 9, 2015 So , I was making a mold of commercial swim bait (the Karma infraction) and it seems this gulpy plastic had some sort of reaction with the silicon and a very , very thin layer did not cure. the detail is 99.99% intact, is there a way to wash out the uncured silicon. I guess a POP mold would have been the better option, if I was to tempt Karma again Quote Link to comment Share on other sites More sharing options...
mark poulson Posted February 9, 2015 Report Share Posted February 9, 2015 I've never had that happen, but, if the rest of the silicone is truly cured, and only a surface layer is uncured, I'd probably try and wash away the soft layer with a solvent like acetone. Acetone shouldn't hurt the cured silicone, if you don't let it sit. I would do a small test on the outside of the mold, just to be sure it won't hurt the mold. If it does hurt the cured silicone, I'd try a lesser solvent, like denatured alcohol, then maybe paint thinner, and lacquer thinner next, testing each one first so I don't ruin the mold. I'm sure you're not the first one to encounter this, so maybe someone who has already solved the problem will chime in. Quote Link to comment Share on other sites More sharing options...
aulrich Posted February 9, 2015 Author Report Share Posted February 9, 2015 You know sometimes common sense comes and smacks you on the head , I have a few options solvent wise that I will test on the bottom of the mold. The rest of the mold seems sound, I guess it all depends on the boundary layer between uncured and cured if it is nice and distinct then I still probably have a useable mold. If I had to guess it would be equivalent to using a clay with sulfur in it in a two part mold setup, sulfur is supposed to inhibit the curing of RTV silicone. Quote Link to comment Share on other sites More sharing options...
mark poulson Posted February 10, 2015 Report Share Posted February 10, 2015 You know sometimes common sense comes and smacks you on the head , I have a few options solvent wise that I will test on the bottom of the mold. The rest of the mold seems sound, I guess it all depends on the boundary layer between uncured and cured if it is nice and distinct then I still probably have a useable mold. If I had to guess it would be equivalent to using a clay with sulfur in it in a two part mold setup, sulfur is supposed to inhibit the curing of RTV silicone. Nowadays, it seems like common sense is a very uncommon thing. Just look at our government! Hahaha Let us know if you are able to salvage the mold. Good luck. Quote Link to comment Share on other sites More sharing options...
aulrich Posted February 10, 2015 Author Report Share Posted February 10, 2015 As it turns out, the mold works, once cleaned out the surface is a bit "tacky", so I expect long term durability is shot at least on the details, I'll have to find some worm oil that should help. The details are rounded but pretty much intact. Quote Link to comment Share on other sites More sharing options...
