Hey everyone, first post here and I'm looking for some advice regarding a foam mold I'm making for vacuum laminating a snowboard of sorts. I've attached a pic of the CAD model I've been working for reference. This mold is going to be machined from sheets of rigid foam insulation board and sanded to it's final shape. I'm looking for the best method of creating a stiff, durable surface on the mold with a very smooth finish. This will hopefully allow me to press multiple snowboards without the mold deteriorating quickly, as well as achieve a more true to design shape on the bottom of the snowboard without having to worry about the foam compressing unevenly.

Thus far I'm thinking about laying two layers of fiberglass over the mold, either chop strand or 6oz biaxial cloth, sand down imperfections/overlaps, fill in more imperfections with some type of body filler, sand again, then brush on a gelcoat as the final layer. Is this the proper course to take? I've also considered just doing a couple hot coats over the fiberglass as well but I'm not confident I could achieve the even surface I'm trying for.

Thanks for the help!