Navegar

Thanks Howard, you do a great job of sharing and explaining your methods and process.

Thanks Howard, I like your plan for finishing the interior of the CB trunk.

I had not seen these before, very interesting here is a woodworkers review and quite positive: http://www.popularwoodworking.com/woodworking-blogs/chris-schwarz-blog/the-venerable-and-inscrutable-shinto-rasp

this reply is in line with post 136 relating to epoxy amine blush and its impact on gelcoat. I agree with Howard (post 137) that in one off plywood construction, paint ( either polyurethane or epoxy based) rather than gelcoat is the preferred solution to protect the epoxy structural bonds from the ravages of the sun. That said some of us need to repair our polyester/gel coated plastic boats. I prefer epoxy to polyester resin for any structural repair. I have found if I water wash off the blush after the repair has cured, I can achieve reliable gel coat adhesion to the faired and washed epoxy repair. My experience is limited to West epoxy, and Evercoat gelcoat. Wet sand the gelcoat nothing heavier than 400 grit, less is better 1000 if you can get it, and then a 2000 grit rubbing compound on a soft rag, all wet. if repairing white gel coat, only tell will be in the slightly grayer shade of the old white gelcoat. the danger will be cutting into and through the preexisting adjacent gelcoat. If that happens you have expanded the gelcoat fairing task. masking can help reduce this risk. West offers the following guidance on this subject: http://www.westsystem.com/ss/polyester-over-epoxy/

I know you are past this point in your build, but what portion of the centerboard trunk is below the designed waterline? I would think at least a minimum of 20 mil of an epoxy paint film should be applied to protect all wood surfaces routinely exposed to water contact. (a 20 mil film build up is recommended for epoxy bottom paint intended to prevent osmotic blistering on old (pre-vinyl-ester) fiberglass hulls) . 20 mill requires four coats of most rolled on bottom paint. if sprayed, it is probably 3 coats. That will be tuff to achieve if the trunk is first made and then coated. I would be inclined to build the trunk in two halves, fully epoxy finish the interior of both halves, and then epoxy bond the two haves together. how do we get future anti-foulant paint into the centerboard trunk to reduce slime and even barnacle growth inside the trunk?