Powdering the inside of the mold prior to casting can improve your pulls. It will help achieve smoother surfaces but will also prolong your mold life a bit, too. Even on silicone, resin tends to want to really grip and pull at the rubber as you demold, and a little talc powder can reduce deterioration.
I would also recommend buying/using a palm sander to help remove air bubbles. This was a trick I used in college with rubber molds meant for plaster/plastic casting. You simply remove the sandpaper square and use the sander for its vibrations. If you hold it against the mold (carefully, of course) the vibrations will cause a lot of those bubbles to rise up to the top of the pour.
Granted, your molds are likely much smaller, so a palm sander could be overkill, but it works great on larger molds for standard masks and other objects. You could maybe try a piece of foam between the sander and the mold to help cut back some of the power. But Iām sure anything that causes pulsations like a palm sander, maybe on a smaller scale, would really help reduce the bubbles youāre worried about.
Also, as far as paint goes, if the heads are cast in resin, thereād be no need to do a latex/acrylic ratio. You could just go straight acrylic. Hand painted in light layers would work nicely with subtle weathering added, or you could try airbrushing your first couple of base layers and then going in and adding the details by hand afterward.
Really looking forward to seeing how this turns out all finished up. Really like the sculpt and seeing on a body form really sets it off. Nice work, man!
Thank you for the tips! Will have to try it out. Yeah I am not a painter yet! I definitely want to paint and hair my own work when I am good enough but I need time and practice for that. Donāt have a whole lot of time though