Once the front of the mould is finished it's flipped over and the clay is removed.
The clay at the base of the sculpture is replaced - this is where the core will uptimately sit so we don't want any mould making material to fill that void just yet.
If we were to start adding resin and fibreglass immediately for the second half of the mould it would stick to the front of the mould, so we need to use a release agent. I've found that vaseline works pretty well in most situations so this is brushed into the edges of the mould.
The second layer of fibre glass for the back of the mould can now be applied.
Once dry this can be cracked open with a screwdriver.
Once the clay is cleared out it looks like this. It's worth giving the edges a trim with a dremel or similar as fibre glass splinters can be really painful!