I have a few cool shaped containers I’d like to use as molds when I pour the polyester resin. Are there certain plastics/metals I shouldn’t use? Right now I have some clear plastic circular bead containers I was going to try out. Thoughts? 🙂
The question comes down to whether or not the plastic is flexible enough to release the casting. If the plastic isn’t polypropylene, it’s unlikely it will work well as a resin mold.