Monster clay solvents that don’t inhibit platinum silicone

Hey there I was wondering if anyone had any advice on solvents to smooth monster clay that don’t cause cure inhibition issues with platinum silicone (smooth on mold star series) (specific brands you’ve had experience with would be great)  also any advice on how long to let any solvent evaporate from the sculpture before moulding would be awesome as well! 



  • Matt WinstonMatt Winston Admin
    edited March 2023
    Hi @Busted toy box - we passed along your question to Monster Clay creator Arnold Goldman from Monster Makers and this is what he had to say:

    "We get this kind of question a lot.

    I've personally never had any issues using Low Odor Mineral Spirits (LOMS). It flashes off relatively quickly, it's lower on the toxicity scale, and does a great job of smoothing Monster Clay. As far as I can tell, it seems to be compatible with platinum silicone. At least the ones from the Polytek line that I have tried.

    Other solvents work as well including makeup solvents like Isopropyl Myristate (IPM). This is especially nice because IPM in particular has no odor and no toxicity. The downside is that it doesn't flash off Monster Clay. Instead, it does soak into the clay and becomes part of it. With IPM it takes about ten to fifteen minutes to do so on average if used lightly. It's also a really aggressive, strong solvent, so you have to use it VERY sparingly or surface details can get too muted and flooded with clay residue. (You can wash any residue away with 70% Isopropyl alcohol which Monster Clay resists because of its high wax content.) IPM also seems compatible with platinum silicone. I can't say for certain with all brands of platinum silicone, but it has worked well for me with the Polytek PlatSil line.

    So I can recommend either IPM or LOMS as best for safety and compatibility. When in doubt, it is always best to do a small test on a scrap piece of clay before committing to a completed sculptural work.

    Hope that answers your question."

  • Mineral Spirit and/or Naptha...i've used silicone from Silicone INC ( my local supplier)...Gel-0020 (BITY Mold Supply) and Dragonskin (Smooth-ON) with NO inhibitions whatsoever...but then again my castign are done IN platinum silicone..any and all mold making/sleeves i do are done in tin-silicone...and even with that there is no inhibitions

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