OK here we go. I have just built a strip wood sea kayak which has been fibreglassed with epoxy resin. The weave of the cloth was then filled with more resin until smooth and rubbed down ready for the finish. The fibreglass is completely wetted out during the initial layup which allows the beauty of the wood to show through. The standard practice for the finish is 6 coats of a good quality spar varnish (Epifavnes or similar) to give some protection including UV as the resin will degrade without.
There is a builder in the USA who uses 2K clearcoat and I have also found a guy on a canoe forum who has used it too. Both have achieved excellent results that have lasted for several years before any revarnishing is required etc apart, of course, for any major scratches when it was flattened and recoated. One of these guys sprayed on the lacquer in controlled conditions and the other sent his kayak to a body shop. I have also found a guy who rolled it on and then laid it off quickly with a varnish brush. I have literally just carried out the latter and apart from a bit of dust I have to say it went on a treat and is now touch dry and in the process of hardening.
My question is a relatively simple one to you experts. I need to build up several coats and bearing in mind that it was put on with a roller, how long must I leave it before recoating and does it need to be flattened between coats? Is it a bit like the epoxy resin which has a minimum time between recoats in order to get a chemical bond (touch dry, usually 4/5 hours) or if left longer than 24 hours it must be sanded to get a key for the next coat. I guess if it’s too quick the new coat of lacquer may well interact/soften the first one too much and cock it all up.
Help/suggestions greatly appreciated
There is a builder in the USA who uses 2K clearcoat and I have also found a guy on a canoe forum who has used it too. Both have achieved excellent results that have lasted for several years before any revarnishing is required etc apart, of course, for any major scratches when it was flattened and recoated. One of these guys sprayed on the lacquer in controlled conditions and the other sent his kayak to a body shop. I have also found a guy who rolled it on and then laid it off quickly with a varnish brush. I have literally just carried out the latter and apart from a bit of dust I have to say it went on a treat and is now touch dry and in the process of hardening.
My question is a relatively simple one to you experts. I need to build up several coats and bearing in mind that it was put on with a roller, how long must I leave it before recoating and does it need to be flattened between coats? Is it a bit like the epoxy resin which has a minimum time between recoats in order to get a chemical bond (touch dry, usually 4/5 hours) or if left longer than 24 hours it must be sanded to get a key for the next coat. I guess if it’s too quick the new coat of lacquer may well interact/soften the first one too much and cock it all up.
Help/suggestions greatly appreciated