If you prefer to make your molds by direct application rather than by pouring, you'll need to modify the silicone you're working with so when you brush it onto your model it doesn't all run off. Viscosil is a chemical thickener that when added to the proper base material will give you nice brushable mixture. Add from .5%-5% by weight to part A of your silicone. Also known at Smooth-On as Thivex!
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