Fiberglass Molding is the complex process, however is impossible doing at your home. Fiberglass molding and casting process is same to other kinds, with a few alterations for the safety, as laminating resin that is used in the casting is very toxic. Best method for fiberglass mold is through the two part mold that is very strong to hold any kind of shape as well as is made to allow hard fiberglass to very easily separate from fiberglass molding.
Coat the model, generally the finished sculpture or else existing the non porous object, in the mold release agent. In case, your model is the soft clay sculpture, bake the sculpture or else coat it in the Krylon Crystal clear, in case you don’t want to save this model. All along middle line of a model, build up the wall of the modeling clay from a side of base to other. Ensure that fiberglass molding clay wall is as tall as you want the fiberglass molding to be.
Mix together gypsum & water in the bucket to make the smooth plaster mixture, as well as apply the impression coat to each side of model, and all way up to fiberglass molding clay line. So, let impression coat cure, and then apply the second layer of the plaster. Over-wet second layer, and lay the strips burl aping to soak a plaster.
Let second-layer to get dry, and then carry on applying the layers of the plaster & burlap till you have the thick, and strong fiberglass mold. Let one side of this model cure, and then repeat this process on opposite side.
Pull a hardened plaster very carefully far away from the model, and separating that at modeling clay line. Also, clean all of clay out of a mold halves, and then coat an inside of fiberglass molding with the paint which should be dried.
Apply the fiberglass molding release agent to an inside of mold. Polyvinyl alcohol is a best mold release agent for the fiberglass molding. Let this mold release agent to dry prior to moving on to a casting stage.
Casting fiberglass molding
Put on the vapor mask as well as the pair of the latex gloves, and then mix up the small batch of the laminating fiberglass resin with the catalyst, and following product instructions on resin container. Then paint the impression coat of the resin in every mold half & let it get set.
Cut some small strips of the fiberglass mold cloth as well as press them in mold halves, and letting them to cover an impression of the coat. Paint the second coat of the laminating resin over fiberglass cloth, and letting a cloth to soak up resin. Let this resin set.
Then apply other coat of the laminating resin & fiberglass mold cloth strips, and building up cast till you have desired thickness. Let this casting to cure partly, for some hours, till fiberglass is firm, however still flexible. Then pull fiberglass from every mold half, and breaking seal between a mold & the fiberglass, and then replace pieces back in fiberglass molding halves. Let fiberglass molding to cure totally.