Subject: epoxy bottom
Date: Mon, 30 Oct 2000
I purchased a 1965 60' custom built boat in 1998. It is 1 1/8 mahogany plank on mahogany frames. The bottom (from waterline down), is covered with multiple layers of epoxy and cloth about 3/8 inch thick. I have pictures of the job being done in Florida in 1988.
I had it out of the water in Port Townsend last year and replace several planks. One plank was half way covered with the epoxy cap. The only rot was above the cap. The wood underneath the epoxy cap looked brand new. Also, when trying to remove the portion of the epoxy on the plank I had to cut a border with a grinder and then apply heat with a torch to remove the piece. Prior to the grinder/torch method, I tried using chisels and large grinders, they all failed to remove the cap. It seems that most shipwrights that I talk to claim the epoxy cap will delaminate over time. I am concerned for safety reasons but also for resale problems.
I would appreciate your opinion and any experience you may have had with this type of situation.
I am located in Raymond, Wash. When I finish the restoration, possible plans for the boat are to take it to mexico. Do you think the warmer climate would be a problem for the boat?
P.S. Great web site.
When the shipwrights say "delaminate over time" I would guess they
really mean "separate from the wood hull over time". The epoxy sheathing
itself should not delaminate in your lifetime.
Since this work was done in 1988 and, as you indicate, the wood looks
fine under the laminate, then I wouldn't worry about it at all. ANYTHING
can happen over enough time, but if there were any built-in problems
they would have showed up on your hull by now. The secret to successful
epoxy sheathing is having absolutely dry wood. Sounds like whoever did
it in Florida did a good job. Be very careful when replacing removed
epoxy sheathing to have dry wood and a premium epoxy to re-make the
Since this boat has been in southern waters and is showing no signs of
significant deterioration, then I wouldn't worry about it too much in
Mexico. Mexico is generally fairly dry. Believe me, if a boat can
survive in Florida it can survive anywhere. I've had boats in Florida
and it's a brutal climate for wood boats.
Because Mexico is warmer, you can expect an increased vulnerability to
above water-line dry rot. Just keep your eye out for it, and get on any
soft wood as soon as possible. I highly recommend that you keep CPES
(Clear Penetrating Epoxy Sealer) on board, and whenever you notice
suspect wood you get after it with the CPES. If CPES had been available
when I had boats in Florida and the Carib and the South Pacific I would
have saved myself a lot of grief. I would also suggest that if you ever
wood the topsides, before applying a new final coat you seal things off
with a coat of CPES. Pay special attention to the sheathing/wood
boundary, because that's where the deterioration will get started -- as
you have already discovered.
Stay in touch with us, and if you have access to a digital camera you
can send us pictures using the jpg format. We're always happy to look at
these and offer any suggestions that come to mind.