The masters for the sides of new Super Barn 119 are made and cooking in a bath of rubber solution.
Beneath all that pink goo, which takes around 24 hours to cure, the masters are glued onto a piece of thick styrene and a box is built up around them.
It is important that the master is bonded properly, that it's completely flat and there are no gaps beneath it that the RTV can flow into because that would ruin the mould.
For that reason I glue it with a generous wash of limonene, which is a very gentle solvent that takes a few minutes to make a sold bond, and squash it under a tower of heavy hardback books to try and ensure there are no gaps.
To save on precious stocks of thick styrene I double up so there is a master on either side.
Obviously enough you can only use them one and a time to make a mould otherwise all the liquid rubber would run out when you turn it over and make rather a mess....