View Full Version : Firberglass Carvel Plank Seams

06-12-2011, 10:21 AM
Hi all,

I know this is probably sinful but I have a leaker and I am considering placing fiberglass cloth (2" wide) epoxied to my keel and garboard plank seam as well as all other below waterline seams to tighten up my boat against leaks. I feel if I have a cracked plank in the future, I can still get the plank off (of course with great difficulty) but I don't expect that to be too likely given how and where she's sailed and I don't want to take the time to pull off the garboards but to simply do the sin and put her in the drink.

Anyone have experience with doing this??

Todd Bradshaw
06-12-2011, 11:58 AM
There is a serious limit to the thickness of a hunk of wood that can be controlled, restrained or whatever else you want to call it using epoxy and fiberglass. This is one very good reason why most of the successful wood/composite boats are built from laminations of thin layers or wood and glass and also a good reason that most attempts to fiberglass-cover traditionally-built timber constructions fail. The fiberglass can't tolerate (or prevent) the greater amount of movement, expansion, contraction, etc. that the wooden structure goes through and the result is usually cracked glass, delamination from the wood and/or more leakage, followed by rot. In order to eliminate this, your fiberglass laminations would need to be massive (to the point of resembling a stand-alone hull in thickness) and the end result is a very heavy hull, that still wouldn't be considered sound boatbuilding or an entirely stable structure.

There are proper ways and materials that boats like yours can be built and with which they can be repaired when needed, usually using more of what built them in the first place. Unfortunately, fiberglass band-aids aren't one of them. They can be expected to fail in fairly short order and may well take the rest of the hull with them. .....and this from a guy who is a big-time composite boat fan. One of the most important things to learn when developing your skills using epoxy and fiberglass is when NOT to use it. Helps keep your failure rate down to a minimum.

06-12-2011, 12:38 PM
Is it leaking because it hasn't had time to swell? Have you used slick seam on it? Is it only after you take her out on a sail? Do you know why, and where it's coming in? These are the questions that need answers. Carvel is a simple build. Might just need the oakum replaced.

Ian McColgin
06-12-2011, 02:26 PM
Fear of cracked planks. Now there's a rare one, unless you regularly collide with stuff. There are lots of things that can be fixed with sheathing but a strip of glass on a seam is about the last word in futility. Just drop that one.

Anyway, sounds like a normal older sailboat, leaking at the garboards. Goblin used to do that a lot since that old schooner when hard pressed to weather wracked so much that none of the athwartships interior doors could be opened if closed or closed if open unless we pointed up into the wind. I became a great fan of my 2" Edson pump - a manual that could lift 55 gpm.

Take at least one garboard plank off and see what you've got. Chances are good the hood ends of the frames are rotten or at least loose and that helps everything work. You can't fix garboard wiggle with a layer of glass on the outside.

If you're in the water, get a good bunch of pumps, both automatic and manual, maybe a solar charger to keep the batteries up while you're away, and suffer along this summer. In the fall, pop that garboard and see what you have.