Now, we mix up our silicone. For the mould itself, we're using a low-viscosity silicone that mixes at a 10-1 ratio. It's much firmer than Gel-10 and has much more resilience. It can even handle up to 500 degrees Farenheit temperatures (in case we feel like making some items out of metal). If you want a mould to last, this is just the kind of material to use.
Once the silicone is mixed, it's a good idea to put your mix into a vacuum chamber. If you don't have access to one, it's okay. But a vacuum chamber helps release any air bubbles in the silicone you just mixed. In the following image, you can see how the silicone froths up. Once a majority of the bubbles have popped, you can release the vacuum and take your silicone ...
