Latex Rubber molding

[heath54]

I am real new to this and wondered if anyone could tell me if a "release compond" is needed when trying to make a mold over raw plaster or any other materials. Thanks - heath54

[the Bach-man]

Dear Heath,
The rubber mold should peel away with no release.
Have fun!
the Bach-man

[Seasaltchap]

If it will not damage the original, I would sieze it with shellac judiciously applied, to ensure the latex compound does not pull away any of the original.

[Bill Baker]

Heath,

I've used rubber molds and the only trouble I've run into is not allowing my plaster to dry sufficiently to remove it from the molds.  Every now and then the plaster rocks will crack when I remove them, but for the most part I have never had any problem.  Another thing to keep in mind is NOT to make your plaster too thin with water.  If it is too thin, your casting doesn't have sufficient strength to remove it from the mold and it will crack.

[heath54]

Thanks to all that replied on the latex rubber molds.  I have some portals to make and will now be able to make them.
Heath

[Seasaltchap]

Bill : I think this reads as making a mould of an original: not making copies from the mould itself.

[Bill Baker]

Hey, I think you're right.  You can sort of read his post both ways.