I personally would hesitate to use wood as a mould, it will require a lot of filler, sanding and preparation. I think Dan has gone to some plastic stuff and for good reason.
Maybe the candle wax treatment or something will get you a release from wood. Someone suggested PTFE film and that will release it. Even silicone coated mylar will probably do, but I am not sure of its availability, we used it on epoxy coil formers. Definitely I would consider petroleum jelly a no go even on well polished metal moulds.
I haven't had experience of vinyl ester but releasing epoxy can be a real pig and it seems as though the basis of vinyl is the same as epoxy so treat it accordingly even if it is less problematic.
Flux[ Parent ]