Cpes, epoxy---- needing advice

[mnbenolken]

Good Morning,
I have a 37' x 8'0" beam Chesapeake work boat that I'm coverting to a cruiser, It was built in 1956. I have replanked the bottom with 1.25"x 1.25" strips of Junniper. These boards run from keal to chine longest being under 60". They have been glued and nail both to one and another and into chine and kealson. The reason for this was to be able to able to be remove for winter months. I will glass the bottom. Now my question is: The bilge area needs to be painted and I would like to seal it first. The west systems supporters want me to sand and coat with thick epoxy then appy an epoxy paint. To me this seems to be a over kill and I'm wondering if CPES would do the same thing. Also when I get to the coach work is it neccessary to glass the vertical wood, I do plan on glassing all hortizonal surfaces. These boats were built in thier day with loblolly pine and managed to last this long with only being painted. Mind you these were work boats so only mimimal care was given them. How far should I take the epoxy part?? Where does one draw the line? Thanks
Mike

[Ian McColgin]

CPES will penetrate rather nicely and, assuming long enough before you're sleeping aboard, you might even leave it at that. No UV afterall. I'd paint over with KillZee or something oil proof and metalic in the engin room but otherwise, why bother?

Granuaile's hull inside was finished with just normal viscosity epoxy and that worked fine.

With any epoxy work in the bilge and most especially with CPES, invest in a proper respirator providing forced fresh air. Keytones on the brain are not good.

[Todd Bradshaw]

I'd probably suggest CPES to improve moisture resistance and then paint. Epoxy resin really isn't made for trying to stabilize wood that thick (and doesn't do a particularly good job of it) and neither is fiberglass unless you use a hell of a lot of it. I don't know who your "WEST System Supporters" are, but they need some education. Slathering a thick layer of unsupported epoxy on anthing produces an expensive, heavy and often very brittle coating. Once you exceed about 10 mils of thickness (the equal of 5-6 carefully and THINLY rolled-on coats of resin or resin with a barrier additive) you get nothing more than weak, brittle resin. As for sheathing, on a boat that size with planking that thick you probably need a lamination of at least 25-30 ounces of cloth layers set in epoxy to keep the glass from splitting, fracturing or delaminating with seasonal movement of the planks. Expecting a single layer or two of lightweight fiberglass to stabilize planking that's more than an inch thick is dreaming. You will notice that the boats which hold up best combining wood layers and epoxy/fiberglass layers do so by combining thin layers of material, rather than with big hunks of thick wood covered with a coating of epoxy resin or epoxy/fiberglass. There is a reason for this. Epoxy and fiberglass are great stuff if used properly, but pretty darned worthless if not.

Alternative sheathing fabrics which have at least a little more flex and stretchability (Dynel, Xynole, etc.) might hold up better, but even so, thick wood planking mixed with epoxy and thin cloth on an old boat is not a great formula for success.