I can't seem to find a straight answer to this anywhere on all of the whole entire internet, so I'm taking it to the forum... If I've sculpted a head in Monster Clay and i'm about to build a mold around the head in Hydro Cal, do i need to seal the Monster Clay sculpture with Crystal Clear or any other adhering preventative? Or can I just apply the Hydro Cal directly to the Monster Clay?

I ask because while it would be great for the mold to just pull away from the sculpture with a non-adhesive applied, it would also be nice to be able to re-use the Monster Clay for other sculpts and I'm guessing the non-adhesive would taint the Monster Clay for future use.

Can anyone advise? Thanks! 


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    Hey Damion, Did you ever get an answer to this? Or maybe by now you did some tests? I'm wondering the same thing. Also wondering if you do use something like Crystal Clear on the Monster Clay if you have to throw out that top layer.

    I recently made a glove mold using silicone caulk/Naptha over a Monster Clay sculpt. I didn't seal the clay and only a little bit remained in the mold. The sculpt had a lot of texture to it and little bits did cling to the silicone. I scrubbed it carefully using Naphtha and it looks pretty good. I'll be casting it in urethane plastic in the next day or so.
    As far as making a mold- I haven't heard of using HydroCal. I've used UltraCal30, and believe that's pretty much industry standard for "stone" molds. I've used UltraCal 30 molds quite a bit for slush casting neoprene. I don't use a sealant if my sculpt is WED clay and if I remove it soon after the mold sets and before it cools completely, the clay comes out easily. Water based clay itself can be watered down to make a slip for casting in stone molds. For casts like neoprene or latex, it's important to not clog the pores of the stone mold. If you're casting something like silicone though, my current understanding is that you probably do want to use sealing and release agents.

    Anyone else out there have any thoughts?
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    You don't need to seal your monster clay sculpture when making a mold, but it helps a lot with mold clean up, as you'll get a little less clay sticking to your mold.

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    I heard that you have to seal a casted project (like out of latex) too before painting.. don't know if anything is necassary, neither on the sculpture than on the casted product.
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