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plaster mold question

updated thu 21 mar 02

 

Chris Stanley on tue 19 mar 02


Try using a cold-water dip on the plaster. Immerse the plaster until there
are no more bubbles and then pour in the wax!

This is the traditional method for wax casting on a plaster mold.

Chris

Scott W on tue 19 mar 02


Hello, I'm not sure this is the right way to send my question to the
list, but I'm giving it a try. I'm currently working with several
plaster molds and pouring a gel wax into them to form the final shapes.
I'm wondering about what kind of Mold release I can use with this type
of project to make the gel wax forms release from the plaster mold
alittle easier. Will something like pam work for this? Thanks

Scott W

Working Potter on tue 19 mar 02


GO TO WWW.PINKHOUSE.COM OR CALL TO ask technical questions, phone (802)
524-7191.
Misty

> Hello, I'm not sure this is the right way to send my question to the
> list, but I'm giving it a try. I'm currently working with several
> plaster molds and pouring a gel wax into them to form the final shapes.
> I'm wondering about what kind of Mold release I can use with this type
> of project to make the gel wax forms release from the plaster mold
> alittle easier. Will something like pam work for this? Thanks
>
> Scott W
>
>
>
>

Snail Scott on wed 20 mar 02


At 09:29 PM 3/19/02 -0500, you wrote:
>...what kind of Mold release I can use with this type
>of project to make the gel wax forms release from the plaster mold
>alittle easier...


I don't know if this is related to what you are doing,
but I pour wax into plaster molds, to make sprues and
gates for lost-wax casting. (I use urethane or silicone
molds backed with plaster to pour the wax for the art,
but I don't need that kind of thing for the sprues.)

A well-soaked plaster mold will release wax very easily.
Fresh plaster requires hardly any soaking, while an old
dry mold may need to be immersed or hosed for a while,
'til it can't absorb any more water. No standing water
should remain in the mold, though, as it disagrees with
the hot wax and causes faults in the wax casting.

I would avoid getting anything oily or waxy stuck to
the molds, as is will actually cause the wax casting
to stick.

-Snail