document updated a month ago, on Dec 8, 2022
Mold-making / casting
https://www.makeyourownmolds.com/how-to/ YouTube playlists:
"Molding & Casting 101", by Punished Props Academy (15 videos, channel has 59,000,000 views) [off-site page]
"Basics of Mold Making How To Videos", by Smooth-On (57 videos, channel has 40,000,000 views) [off-site page]
"Basics of Mold Making", by Alumilite Mold Making & Casting Materials (37 videos, channel has 10,000,000 views) [off-site page]
"Basics of Moldmaking and Casting Videos", by Reynolds Advanced Materials (34 videos, channel has 2,400,000 views) [off-site page]
"Moldmaking 101: Beginner Tutorials (RAW)", by Iconic Props (9 videos, channel has 30,000 views)
"Molding 101", by Dor Friedman (27 videos, channel has 300 views)
"Casting, molds, duplicates", by GroundPound MagX (21 videos) — specializes in cheaper / makeshift alternatives (
davidneat.wordpress.com/methods/mouldmaking-and-casting/beginners-basics-mouldmaking-and-casting-explained/ RTV (room temperature vulcanizing) mold rubber
If you want a high-quality finish, then
small air bubbles are a big concern. There are several solutions including compressed air and vacuum degassing, but it seems like most professionals settle on pressure pots as the best overall solution.
The downsides of vacuum degassing include — longer production times because you have to wait for silicone to degas before you can use it, it's incompatible with silicone materials that have a short work time, and when degassing, you have to use a cup that's at least twice the volume of the silicone, and still there's always a risk of overflowing and making a mess.
molds are used
a LOT in industrial settings too, of course, and it's possible some of their literature can be relevant to smaller-scale mold-making