re molds

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Original poster: "Allan Scott" <ascott16-at-cogeco.ca> 

Hi im the one that posted that info i used to work for a company a few 
years back
we made water fountains , Bird baths ect.
out of concrete or plaster and when we made the molds from various objects 
we used clay to fill in imperfections to make shure every thing was smooth 
then the
object was coated with a lubricant then
coated with a brush on rubber, about 3 or 4 coats.
to make the rubber removable tape 2 pieces of cardboard to the object (on 
edge) close together before coating with rubber. this gives you a seem that 
you can open after drying keep in mind that
the mold creation process gets trickey if you want your finished product to 
be light
and hollow (create a negative and a positive) for example cut a toriod in half
horizontally so you can coat inside and outside surfaces with rubber you 
also have to keep venting in mind to allow flow of poured substance to both 
halves and air to escape from the mold as you pour the substance then when 
that process is complete we coated the whole thing with plaster(making 2 
removable halves again) the reason for the plaster on the outside is to 
give the rubber support to keep its shape the bottom beeing the opening for 
pouring later and air to escape
and to assist in air escaping while pouring we just simply shook and 
bounced the molds
and before we poured we coated the rubber with vassilene or water so the rubber
would be easy to remove to take out the finished piece.
and of coarse you have a reusable mold.
a good pouring substance might be fiberglass resin then when it hardens 
cover with
aluminum tape or possibly plate it