A mold release, also known as a parting agent, is used to allow parts to be easily removed from the original plug or mold. It also adds a durable surface finish to the part.
It is important to use a mold release when working with molds. The two most popular mold releases used are a wax and a PVA (polyvinyl alcohol). When used together, they form a great release system.
A mold release helps the mold last longer and protects against damage. Even though it can be time consuming to add a mold release, it is worth it.
A mold release wax can be rubbed on evenly similar to waxing a car. It should dry between layers but not for too long, as it will be more difficult to wax off. Several layers are recommended.
Next a PVA solution of water-soluble, film forming material can be used. It can be brushed on but it is ideal to use a spray gun when applying it. PVA needs to have at least three layers (more can be used if desired). The PVA needs to dry completely between each layer. PVA will clean off easily and leaves a tack free surface.