by Rodney Syverson » Tue Apr 11, 2006 5:03 pm
Dan:
Your concern with utilizing epoxies is valid. Usually encapsulation of wood with epoxies is the kiss of death for a wooden boat, even though it is touted to be an acceptable procedure for salvaging wood boats by some boat restorers. The term epoxy is a general term applied to any two part component where the combination creates a solid or semi solid product, weather it is paint, primers, sealers or adhesives. People call anything they have to mix together an epoxy.
CPES appears to be unlike any other epoxy in that it does not get hard and it supposedly breathes, which you might guess allows the migration of moisture into the wood. The key is, water molecules are larger than gas molecules. Hence a greater barrier for water to get in and gas to get out. A hard epoxy like a polyester resin or epoxy resin will offer a permanent barrier that will not allow passage of water until it cracks. And on a boat or anything that flexes it will crack. Then the water molecules have clear passage to wick into the wood which will eventually become saturated and the uncracked areas are sealing perfectly and will not allow the moisture to gas out. Eventually the wood turns to punk.
I had the same questions you have until I started reading Danenberg's articles in Classic Boating magazine and his two books. Everything he says appears to be spot on in my book. He bristles at the thought of encapsulating wood with epoxies, even though it is done by big buck restoration shops, but he stands by CPES and has had enormous experience and success with it.
The original manufactures did not have the products available to them that we have now. We just need to decide what is best with the information we have. I firmly believe Danenberg is right and have followed his recomendations.
The underside of your deck no doubt could get by with out sealers as that is high and dry but any area exposed to serious moisture really needs to be sealed. The original manufactures I firmly believe did not go overboard on this as it no doubt was a significant factor in manufacturing, schedules and costs for a boat not expected to have more than a 6 year life span. I often wonder how many years more I would have gotten out of my 62 Sea Lancer ribs had the backside of the ribs had they been properly sealed. There was virtually no sealant on the back sides and with out exception they all exhibited some signs of deterioration. Sure they gave probably 30 years of useful life but I have to believe they would have gone further if they had not been wicking moisture out of the bottom of the boat.
Rod