Re: Faux Teak and Deck Paint
Mark,toggle quoted messageShow quoted text
That is not a stupid question, in fact it is a great one! It is certainly possible to recoat gelcoat with new gelcoat. In general however it is important to understand that the gelcoat used for boatbuilding are “air inhibited cure”. This means that the exposure to air prevents a full cure so the surface remains soft and tacky. This is a benefit when boatbuilding since this increases the bond between the gel coat and the layers of fibreglass being added. The gelcoat against the mold itself cures nice and hard since air is excluded. So there are additives that can be used with regular gelcoat or coatings that can applied allow the gelcoat to fully cure. One is simply a wax additive which floats to the surface and helps exclude the air, another option is to spray the fresh gelcoat with PVA which is poly vinyl acetate, it just forms a film over the gelcoat to exclude the air. You can just wash the PVA off with water later after the gel coat is fully cured. There are also some specialty additives that you can purchase from major suppliers of polyester resins, some of which work well when patching gelcoat. So you want to use one of these options to help your gelcoat cure properly on the surface if you are using regular boat building type gel coat. There are also non air inhibited gel coats and I have used one called Simtec Prestec which can be tinted to any colour. The material cures hard as glass without any additives but for some reason the UV resistance is inferior. I have never looked into the reason but there could be other non air inhibited gel coats that have better UV resistance. New gelcoat will bond pretty well to old gel coat if you really roughen up the surface and do not have any contaminants on the surface. 60-80 grit would not be too coarse. I am absolutely sure that if done correctly that gel coat will outlast any one part paint and possibly even the two part paints. Unfortunately gel coat is not too easy to brush on. So you have to apply it smoothly since It does not self level like paints do.. Adding some styrene thinner can help with brushing some but mostly you need to apply it as smooth as possible via your technique. The good thing with the gel coat is that if you have thick or uneven spots you can come back and sand and polish out those areas but what a lot of work that would be if you had a lot of them! So yes, this is actually an excellent idea IMO.