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Re: Skin-on-Frame: epoxy the plywood form edges or
By:Paul G. Jacobson
Date: 3/23/2011, 1:14 pm

: Wood will never completely dry out, it doesn't need to. I am not
: looking for a debate. It's your boat and your money. I just know
: what happens on a encapsulated boat when the seal is broken and
: water gets in.

I'm not too sure about how "the seal is broken" on a part where the epoxy has saturated in about 1/8 inch on each side. Seems like anything that did that much structural damage would create an immediate problem, and be replaced or repaired many years before it could rot.

Unlike the earlier fiberglassing-over-wood projects which used polyester resin, epoxy is more flexible and goes in deeper. Polyester just kinda sits on top of the wood.

: Doesn't always happen but if it does the results
: are worse than if you didn't coat it. Go over to Wooden Boat
: forum and search some of the past posts. It stirs a lot debate
: but there are examples of boats rotting that were sealed in
: epoxy.

I have to wonder if some of these were sealed in epoxy, or in fiberglass (polyester based). I've seen a lot of people get confused about what they were buying, and some refer to whatever plastic they they use as "epoxy" even if it is a urethane or a vinyl-ester. Pettit's line of boat paints called "Poly-Poxy", for example suggest that they are epoxy based. But they are a single solution--no hardener-- so they can't be setting up the same way that true epoxys do. Similarly there are urethane coatings for garage and bassement floors which are marketed as "epoxy floor systems". There is a lot of confusion in the market. I would be surprised to find problems in boats that were truly encapsulated (covered on all sides with at least two coats) with a brand name epoxy.

: Once the water gets in there is no way for it to dry and
: they rot from the inside out.

Actually, one of the "faults" of epoxy is that trapped air can form bubbles under the glass. Trapped moisture does the same thing if the boat is exposed to hot sunlight. The water turns to vapor and forms bubbles. Popping those bubbles and filling them seems to be a common repair. Once they are gone, they are gone.

PGJ

Messages In This Thread

Skin-on-Frame: epoxy the plywood form edges or not?
Todd O -- 3/21/2011, 1:29 pm
Re: Skin-on-Frame: epoxy the plywood form edges or
Dave Gentry -- 3/21/2011, 1:50 pm
Re: Skin-on-Frame: epoxy the plywood form edges or
Foster -- 3/21/2011, 6:04 pm
Re: Skin-on-Frame: epoxy the plywood form edges or
Charlie -- 3/21/2011, 6:20 pm
Re: Skin-on-Frame: epoxy the plywood form edges or
Kudzu / Jeff Horton -- 3/22/2011, 8:24 am
Re: Skin-on-Frame: epoxy the plywood form edges or
Charlie -- 3/22/2011, 2:30 pm
Re: Skin-on-Frame: epoxy the plywood form edges or
Kudzu -- 3/22/2011, 2:45 pm
Re: Skin-on-Frame: epoxy the plywood form edges or
Charlie -- 3/22/2011, 3:40 pm
Re: Skin-on-Frame: epoxy the plywood form edges or
Bill Hamm -- 3/23/2011, 1:50 am
Re: Skin-on-Frame: epoxy the plywood form edges or
ancient kayaker -- 3/23/2011, 9:13 pm
Re: Skin-on-Frame: epoxy the plywood form edges or
Bill Hamm -- 3/23/2011, 9:20 pm
Re: Skin-on-Frame: epoxy the plywood form edges or
Bill Hamm -- 3/23/2011, 1:45 am
Re: Skin-on-Frame: epoxy the plywood form edges or
Paul G. Jacobson -- 3/23/2011, 1:14 pm
Re: Skin-on-Frame: epoxy the plywood form edges or
Bill Hamm -- 3/22/2011, 2:21 am
Re: Skin-on-Frame: epoxy the plywood form edges or *PIC*
Tom Yost -- 3/23/2011, 11:37 am
Re: Skin-on-Frame: epoxy the plywood form edges or
Todd O -- 3/23/2011, 12:26 pm
Re: Skin-on-Frame: epoxy the plywood form edges or
Bill Hamm -- 3/23/2011, 1:59 pm
Re: Skin-on-Frame: epoxy the plywood form edges or
Bill Hamm -- 3/23/2011, 2:01 pm
Re: Skin-on-Frame: epoxy the plywood form edges or
Todd O -- 3/23/2011, 3:12 pm
Re: Skin-on-Frame: epoxy the plywood form edges or
Bill Hamm -- 3/23/2011, 4:04 pm
Re: Skin-on-Frame: epoxy the plywood form edges or
Foster -- 3/24/2011, 12:56 am
Re: Skin-on-Frame: epoxy the plywood form edges or
Bill Hamm -- 3/24/2011, 7:38 am