iains123
New member
has anyone experience of marine ply decks / coachroofs that have been epoxy encapsulated - shrinkage/damp ingress or any other problems??
epoxy encapsulated marine ply-any views?
- Thread starter iains123
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jamesjermain
Active member
Do you mean encapsulated or do you mean impregnated/saturated? If the former, then water ingress and rot are serious problems. If the latter, then it is the way to go to preserve wooden decks etc.
JJ
JJ
chas
New member
If you really mean encapsulated, my experience (with a sailing dinghy) is fine until the first bit of damage - then, if not treated immediately, rot, delayering etc. I do not think I would have another one!
oldharry
Well-known member
Many of us have had major bad experiences of 'sheathed' marine ply, and success or otherwise depends on how carefully the work was done. You specify epoxy encapsulation, which if done properly is reasonably effective - provided , as James G points out, the sheathing is never damaged.
As an aside, the old 60's/70's practise of using polyester GRP to cover old plywood hulls and decks to cure leaks is a guaranteed way of hastening the demise of the ply. Polyester does not adhere at all well to wood unless the moisture content is around 15% max. And no boat that has been in the water can easily be dried to that level! The end result of a higher moisture content is failure of the resin/wood bond. Water then enters and rot ensues within months.
The same rule applies with epoxy. The timber MUST be of very low moisture content before epoxy is applied. Ply direct from the store is dry enough. Ply that has been in the water can be assumed to be too damp unless force dried.
If this rule is observed, epoxy sheathing of new hulls and decks can be entirely satisfactory, and with care older hulls may also be preserved.
But James G's caution about damage must still be observed - any point at which water can penetrate the encapsualtion - whether by damage, or by fittings and fastenings that have not been thoroughly sealed, is immediately suspect as the timber underneath will rot out very quickly.
If by encapsulation you mean impregnation with epoxy resins, then this is a totally differnet ball game, and is a highly effective means of preserving timber if done properly.
As an aside, the old 60's/70's practise of using polyester GRP to cover old plywood hulls and decks to cure leaks is a guaranteed way of hastening the demise of the ply. Polyester does not adhere at all well to wood unless the moisture content is around 15% max. And no boat that has been in the water can easily be dried to that level! The end result of a higher moisture content is failure of the resin/wood bond. Water then enters and rot ensues within months.
The same rule applies with epoxy. The timber MUST be of very low moisture content before epoxy is applied. Ply direct from the store is dry enough. Ply that has been in the water can be assumed to be too damp unless force dried.
If this rule is observed, epoxy sheathing of new hulls and decks can be entirely satisfactory, and with care older hulls may also be preserved.
But James G's caution about damage must still be observed - any point at which water can penetrate the encapsualtion - whether by damage, or by fittings and fastenings that have not been thoroughly sealed, is immediately suspect as the timber underneath will rot out very quickly.
If by encapsulation you mean impregnation with epoxy resins, then this is a totally differnet ball game, and is a highly effective means of preserving timber if done properly.
G
Guest
Guest
Many years ago I bought a 1960s vintage Bobcat that had been "sheathed" - probably with polyester resin.
On later inspection - sadly after the euphoria of the sale had worn off - I found several areas where the sheathing had failed and extensive rot had set in.
I vowed never again to buy any vessel which relied on sheathed ply to keep out the water. Buyer beware!
On later inspection - sadly after the euphoria of the sale had worn off - I found several areas where the sheathing had failed and extensive rot had set in.
I vowed never again to buy any vessel which relied on sheathed ply to keep out the water. Buyer beware!
