Making a fibre glass head

Once all the pieces of the various fibre glass jackets had been separated from the original head cast they needed to be cleaned up as a lot of the dried shellac, plaster and clay had transferred onto the inside of the silicone, and any loose pieces of silicone from the base trimmed off.
It was also recommended to us that we use a small amount of super glue to tack the edges of the silicone into the fibre glass jacket to ensure that it stayed tightly in place during the fibre glassing process and did not lift up, warping the overall shape of the finished head and creating a step on the seam.
When it came to fibre glassing the inside of the mould we made the decision to pigment the resin and gel coat with white so that it would be easier to sculpt on at a later stage. We followed through with our plan to apply a thin layer of chopped strand into the face first, then a finer fibre glass layer and then two layers of the thicker fibre glass. I was slightly concerned about any air bubbles appearing in the nose as it was a very tight space so was forced to spend a little extra time on this particular area getting it all down.
Once all of the layers of fibre glass were completed on both sides of the jacket the two needed to be pushed back together, tilting them upwards gradually from the keys at the top of the head to prevent the fibre glass from sagging down as the process needs to be completed before the fibre glass is dry. M620 screws were then used to secure the jacket and wound very tightly to ensure that the edges of the silicone were as close together as possible. Finally thinner strips of fibre glass were cut out and needed to applied (2-3 layers) to the inside of the closed mould to cover the seam. This was a very frustrating task as it was obviously very difficult to get good access to the area being fibre glassed through the small hole in the neck of the mould and a lot of the strips had a tendency to lift up once they had been patted down. As an additional consideration we applied a finer layer of fibre glass around the inside of the base of the cast (shoulders, neck, etc) so that there would be no sharp shards of fibre glass sticking out when we handled the finished head.

The finished heads were left to dry and then removed from their jackets where they could then have any rough edges sanded down and any dents/seams filled in with car body filler which was then also sanded down with wet and dry paper. I did notice that on John's head his nose appeared to have a sizeable dent in it, however, it is difficult to tell how much of this is due to the fibre glass sagging and how much is actually his nose, which has been broken a number of times in the past. The head is however, perfectly usable and could have clay sculpted onto it immediately.