Ultracal 30 molding problems?

Hey guys! How is everyone? I just recently made an Ultracal30 mold for my Halloween 4 mask that I sculpted, but I’m running into a few errors. My main priority is that after every pull there seem to be a crap ton more bubbles present. I’m aware that it’s likely to have bubbles and cavities form after the more pulls you do, but after the 4th or 5th one just doesn’t seem right. Am I doing something wrong, or is it really that normal? Thank you! Excited to see the replies here. Is it possible to mix in dental stone to fix this? If so, how much? Thanks guys! 


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    You can mix in some dental stone to make it a bit stronger, but I don't believe that will help you with air bubbles.

    One trick to help with bubbles when making the mold is to brush on thin layers of Ultracal 30 at first and use an air compressor or straw to blow them around on the surface.  This will pop bubbles and push the material into small details.

    You can also use a shaker table or shake/bump/tap the mold a lot to try and release air bubbles before the Ultracal starts to set.  It's also good to mix things carefully so you are not whipping more air into the mixture.

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