To continue from the previous blog describing the various processes involved with realising a commissioned project (the bronze bust of a clients flat coated retriever), the completed Plasticine maquette (pictured right) was taken to the foundry about two weeks ago.
Since then, the maquette has had a silicone rubber mold made around it and a glass fibre casing built around that to keep the rubber in place. Once the rubber had cured, the case was taken apart and the Plasticine maquette removed. The now empty rubber mold was put back into the fibre glass case as you can see pictured below.
Molten wax (in this case red in colour) is poured into the void within the mold, sloshed around (in a very skilful way so that it reaches into every cranny without leaving air bubbles) and then poured out.
This process is repeated as many times at it takes to build up an even layer of wax within the mold to a thickness of around 4-6 mm.
Once this wax layer has cooled enough to be handled, the casing and rubber is removed to expose a now hollow wax replica of the original Plasticine.
Before the next stages of casting can take place, this wax replica is checked over for any imperfections (and made good) and any seem lines, that are visible from the rubber mold, are re-sculpted and blended in (pictured right).
The final stages of the casting process will soon be covered in another blog.