Do I need to coat / shellac a plaster Cast before adding Monster Clay?


I'm doing my first mask using Monster Clay and I have a plaster bust to apply the clay on.

Do I need to seal the plaster surface with a shellac or lacquer? Or can I just start adding clay on the plaster?

Any advice or tip is welcome at this point :)

Thanks in advance


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    It all depends on what you have planned for that plaster bust in the future.  Without sealing it the clay will stick in small pores and can stain or discolor the plaster a bit, but if you just plan on using that bust for more sculpting you are fine as-is.  Any bust that I dedicate just to sculpting is raw stone with no sealant, but that's just me!

    Coating it with anything that will act as a release would prevent staining and make the bust easier to clean, but could also prevent your clay from adhering to the mold as well, which is something you want when sculpting.

    Though if you are working with a water based clay you would likely want to seal the plaster to prevent it from pulling the moisture out of your clay, causing it to dry/crack faster.  In that case I would probably seal it with something like Krylon crystal clear.   I rarely work with water based clays (I'm pretty much 100% plasticine like Chavant NSP), so if anyone out there works with water clay a lot please chime in, as I too would like to hear what you think!

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    Brilliant! Thanks for the advice Chris.

    Just one question... With "raw stone" do you mean plaster / gypsum?

    I'm using monsterclay which I guess is more like NSP / plasticine and the plaster bust is only for sculpting the mask I don't mind it getting stained or anything.

    And one additional issue you might be able to help with.

    I'm still waiting for the plaster to dry out though. Which sucks since I would like to start working. It's solid and movable but the surface feels a bit cold / damp.

    Should I wait for it to dry out fully or can I just start applying MonsterClay on it? 

    For the future could you recommend a substitute for using plaster in lifecasts / busts? Maybe some resins / foams etc?

    Thank you again for your reply!
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    Correct, stone is another way of referring to plaster/gypsum.

    You can start sculpting with monster clay before the plaster lets go of all its internal moisture.  The plaster will continue to dry out through any exposed surface, so it will just dry slower once your start applying clay. 

    Plaster is great for busts, but if you want another material epoxy/resin/fiberglass work great and are much lighter, and you can fill them with a 2 part expanding foam to make them more solid while keeping the weight down.  They are just more expensive to make.

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    Thanks Chris. 

    Can't thank you enough for these tips.
    Great to start working on this project.

    I haven't found anyone else doing this sort of stuff in Finland getting info or help locally here is impossible.

    Thank you very much for this and I'll be sure to return on this forum for more help as go on :) Most likely...

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    My pleasure!  I hope you can share some photos of your project here too!

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