Hi there, I was wondering if anyone has ever tried to make moulds of their work?
I have a couple concepts that I am perfecting and when I get to the version I like, I’d like to be able to replicate it using a mould. So couple of questions:
anyone with mould making experience want to teach me what you know? I know some shapes will be harder than others
has anyone in the studio used plaster, and is it better/worse/same than slip casting?
2a) can we fire glazes on plaster in our kilns?
Are you looking to use plaster to create a slip cast mold, or are you trying to make a slump/hump mold?
I’m unsure what you mean by “is using plaster better.. than slip casting”. Plaster is used to make the molds for slip casting. They’re different steps of the same process, not standalone processes.
Plaster is used as a mold for ceramics because it’s very porous and wicks water out of the clay quickly. This allows for a relatively quick release from the mold if using them for slump/humo style work, and is the very principle by which slip casting works (plaster dries out a layer of clay around the mold, allowing the excess slip to be poured off)
2.a Plaster cannot be fired, it would crack. It is like cement, and cures in an exothermic reaction with water. It expands when it cures. Ceramics are kinda the opposite, being turned from “mud” into glass when fired at high temperatures. It shrinks while this happens.
There are a few of us here that have made molds for ceramics before. Once we have a better idea of what you’re looking to do I think folks will be able to help you out!
I guess I assumed I would make a mould from rubber and pour plaster into it, and get out of it what you would at one of those places where you have a kids birthday party and paint a piggy bank etc.
But what I’m gathering from your response is that I need to use plaster as what I pour slip into.
It also seems that the shape probably dictates if its slip cast or slump/hump?
Essentially I want to create a more elaborate/quality version of a wall planter (unfortunately it wont let me post a link or embed an image
Good to know there are folks who have done this.. I’ll work out my idea and reach out when I am fully ready!
Ahhhh, yes. You’re correct in that the rubber/silicone mold is only used in the first part of the process, to make the plaster mold to then make the object out of clay.
Also correct re:slump/hump or slipcasting. They’re different processes, but the shape of what you’re looking to do does dictate which one you could move forward with.
Looking forward to learning more about what your plans are!
I would LOVE a class on mold making for ceramics. I have a BFA but was never taught this and even bought books on it which aren’t an easy guide. Several things I’d love to do with slip casting for adding elements to my works.