Here are some videos covering vacuum degassing silicone and pressure casting resin. I’ve shown the process in various of my videos previously but I thought it might be useful to have some videos specifically about it for reference. These videos were made at the same time so they’re designed to go hand in hand.
I think there’s often some confusion as to when you would vacuum degas something and when you would pressure cast something, certainly when I first came to start doing this I was a little bit confused as to when you would use both processes. Generally speaking you vacuum degas silicon when you’re making a mould. Pressure casting is used when you are pouring resin into a mould to create a cast and the idea is that you put the mould and casting material within it under pressure. What that does is to cause any bubbles that get trapped in your mould to be crushed down to tiny points, thus eliminating any air bubbles in your cast.