mold releases/ inhibit x - Kenneth "Super Ken" Calhoun's encapsulated prosthethic question


I am working on my first "encapsulated" prosthetic project. In the "casting your negative copy" chapter in part1. Ken uses "inhibit x" on his master molds made out of 65D. To avoid any kind of issues with the titanium silicone curing due to surface "issues".

Since he mentioned the trick about using the stone instead of the 65D. I was going to make my master out of Hydrostone. I was thinking I wouldn't need the inhibit X in that case. Also seems like this is used mainly when casting from a material that may have sulfur residue (clays or PVAs). Any reason to worry about casting sorta clear molds from a hydrostone master?

Just to be clear:

step1: I pour a hydrostone base in a zip lok of appropriate size (yes, a little Brad Look crossover)
step2: I sculpt my prosthethic in monster clay (oil based, silicone safe)
step3: I use Ultra 4 Epoxy Parfilm *asking, I don't have this yet* spray thin layer
step4: pour my 1/4" thick above the sculpt layer of Smooth On Sorta Clear 37
step5: let cure overnight
step6: mold walls / hydrostone master
step7: create as many needed copies of Prosthethic or just keep master in case the one you create in step4 fails


Andy - Lotek514


  • Hello Andy, 
    This is a great question. I don’t see any reason why you would have any issue running sorta clear in a hydrostone master. If you do have any issues, I’d suggest sealing the stone master with a layer of vasaline, heating it with a hair dryer and then buffing it out. You could even seal the stone with a bit of crystal clear or final seal as well as a cheaper way to prevent any inhibition instead of inhibit X. Let me know how it works out, and if you have any issues feel free to reach out. Good luck. 

    Kenneth Calhoun
  • Hi Kenneth,

    Wow! I really appreciate you taking the time to answer my question! Your class was excellent and I do hope we'll get a chance to see more great content from you soon. The opportunity to see artists such as yourself at work, who are normally behind the scenes is just awesome. Thanks for being so generous of your time and expertise

    I hope to share some progress pics of hands on application of your class soon, 


    Andy (Lotek514)
  • It’s my pleasure Andy! Yes, please feel free to send me photos. I would love to see what you create! 
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