Pros and Cons of fiberglassing a wooden boat

[tchiffriller]

What are the pros and cons of fiberglassing a wooden dinghy such as an 11 foot skiff, or something of the sort.



Thanks,
Tommy

[Jay Greer]

A bit more information concerning your boat would be helpful, such as type of wood and construction as well as why you want to glass your boat.
Jay

[John B]

some pretty good remarks in this thread.

http://www.woodenboatvb.com/vbulletin/upload/showthread.php?t=64379

[outofthenorm]

Completely different answers depending whether it's new construction, young, old, or very old. More info needed.

[tchiffriller]

It is a plywood Poorboy Skiff, by Steve Lewis.

[Ian McColgin]

Plywood is easily glassed. Get down to wood, seal with CPES, light sand an wash to get rid of the amine blush and then use epoxy to set the glass.

There are a number of techniques that help get the glass down on the panels smoothly. Perhaps the Godgeon Brother's book displays this as well as any, but whatever you do, get an idea how to put down epoxy to tacky, how to lay cloth on that, how to wet out ridding all bubble, and all that good stuff, before you make too horrid a mess.

G'luck

[outofthenorm]

Do exactly what Ian said. Is there any where else you could get a first rate answer so fast? :)

- Norm

[Todd Bradshaw]

CPES under epoxy fiberglass does nothing but waste money. The epoxy/fiberglass alone will do the job (and probably better).

[tchiffriller]

Me and my friend had been talking about it for awhile and there is no where else you can get a first rate answer so fast. haha.

[RodB]

If you have not constructed it yet, you can glass the hull panels before assembly on the horizontal... which is very easy and the end results is a much tougher craft that has a solid barrier to moisture and abrasion.

RB

[Ian McColgin]

Todd raises an interesting point and I wish there were good objective data to back up my opinion. I am most impressed with CPES's authentic penetrating ability, far more than just thinning anything else, but this is of less import in all new construction. I seal with CPES now and recommend it but long before I'd heard of CPES I just epoxie-glassed and those jobs have lasted rather well also. You will get a fine job without the CPES. It's possible that I've carried my very good experience with CPES on plywood with no glass - an outstanding improvement over just painting or using other epoxies - past any cost-effective reality and that the CPES deep seal is not such a deal under glass.

Your call.

[Todd Bradshaw]

While I can certainly see the merits of CPES as a tenacious primer and semi-sealer under paint or varnish(it can't be a total seal because anything chocked full of evaporating solvents leaves lots of tiny holes when they evaporate), it has no real merit under epoxy resin. Assuming that you have a properly prepared plywood surface and that you can follow standard epoxy application procedures, regular resin on wood is all you need. If resin frequently had problems sticking to the plywood, the sealer might add something, but resin sticks extremely well to plywood all by itself and the bond will exceed the grain strength of the wood. If resin was not capable of sealing plywood well against moisture, then maybe CPES would boost it's sealing powers - but epoxy resin seals plywood about as well as any substance known to man - and is far better than CPES at that job (no evaporating solvents =no holes).

I would suggest that anyone interested in the subject read the article in Epoxyworks Magazine (on line at epoxyworks.com - then click the "articles by subject tab" then "epoxy techniques" and scroll down to "Thinning WEST System Epoxy".)

[RodB]

During my new build of my flats skiff I had CPES available for specific uses for insurance sake. I had a couple of conversations with Smith and Co. about it and made my decisions accordingly. I also have read recommended sources on this product both on this forum and other sites.

When I drilled a hole through the hull or console, etc, I soaked CPES in the end grain liberally, then after it cured 18- 24 hours in the Texas heat, I double coated the interior of the holes with epoxy before installing hardware. Epoxy has no problem adhering to CPES saturated wood if it is cured...

I also used CPES on the interior surface of my bottom panels before glassing... where water would stand in my bilge... in front of the transom drains extending about 6 feet forward about 15 inches on each side of the center stringer. Now The CPES definitely soaked into the Okoume ply deeper than the epoxy and I am convinced it will also act as an additional barrier to moisture if the epoxy/fiberglass is ever physically damaged.

I am a fan of CPES, and I realize this was overkill, but I am convinced a good soaking with CPES couldn't hurt anything, and most likely is added protection. I only used it in such circumstances as described, which seems reasonable if you consider its attributes.

RB