+x+x+xMade mould,dry nicely but still can see through gelcoat.I mean it not went completely " milky". I used 3 layers.One for coupling coat and 2 after.
Should I apply another layer of fiberglass?
picture was taken before full cure.
You need a minimum of 4 layers of 450g CSM when using tooling resin, NOT including the coupling coat. Hopefully the layers you have already done will still cure properly, as tooling resin actually needs to bake itself with the heat it generates from its exotherm during cure to achieve full mechanical properties.
For a one off the mould will probably be ok, so just sand the surface with 80 grit before adding another 2 layers of 450g.
What can you suggest for mould reinforcment?
After all layers I was planning to fibreglass in wooden frame in to mould stiffen mould and be able to stand mould.upside down.I was thinking about some kind of ribs to make reinforcment (what kind of material can be used?).
Wood will work.
To be honest, I don't like to use supporting structures, they can cause a lot of problems. I prefer my moulds to be rigid enough to not need them, and in cases where it would require a lot of reinforcement to get that rigidity I like to add a 50mm return on the flanges to add natural stiffness.