Constructing a settee

[JonnyBoats]

In my LeComte NorthEast 38 built in 1967 all the interior woodwork is just that, there is no liner. The predominate material for the bunks, cabinets, bulkheads etc is marine plywood.

There has been standing water over the cabin sole on more than one occasion before we purchased the boat. Where the water got into the plywood de-lamination has occured.

I am in the process of replacing the setee on the port side around the dinette table. I am wondering what the best way is to construct the vertical piece under the setee? (The piece that the back of your calfs press against when you are sitting down.)

Originally LeComte took the plywood all the way to direct contact with the hull. The idea being that items placed in the locker under the setee would not roll into the bilge. Unfortunately water will not drain either.

I am placing a new fuel tank (diesel) under the setee and am torn between:

1) Fiberglassing the plywood to the hull and covering the inside of the plywood with fiberglass. The idea being that if the fuel tank should ever spring a leak hopefully the diesel would be contained in the setee and not run into the deep bilge.

2) Leaving the plywood about a quarter of an inch proud of the fiberglass so that any water can easily run into the deep bilge. Since this is below the level of the cabin sole, this will not show. Unfortunately something like a pencil could also roll under the plywood into the deep bilge.

There are of course numerous variants on the theme, such as cutting some PVC pipe in half and glassing it under a notch in the plywood to act as a limber hole.

Anyway I rather suspect that there is a tried and true option 3 of which I am unaware. How are these setees usually constructed?

[Hirilondë]

It never ceases to amaze me when I do interior work how some production boats were built. I was replacing the delaminating sole of a Gulfstar when I discovered how the sole frame work was built. It was construction grade 2x4s sort of tabbed to the hull and nailed together with bright common nails. The plywood was then screwed down with no protection on the back side at all. Any of the options you list are better than what many manufacturers do.

Your option #1 is top shelf. The key to longevity would be to seal all edges and surfaces of the plywood you wont be able to get to after installation. Limber holes are for allowing draining in the bilge for common routes water might take to assure it all ends up in the sump compartment. I don't think you need any for your settee compartment regardless of what you put in it. So long as the puddle that may form in it can't saturate the plywood you should be fine. But it wont hurt to have one provided you seal the inside edges of the hole well. I don't think you need to glass the entire interior surface. A good coating of epoxy or even paint will sufficiently protect it.

Another option would be to glue a cleat to the hull along the bottom of the new settee bulkhead and screw the plywood to it. This is one of the few applications I would consider using 5200 for. For this option I would pre-varnish the plywood piece after a careful dry fit, especially hidden edges. Your 1/4" gap for breathing purposes is a good idea, less chance for trapped moisture working into the edge of the plywood.

Anyway I rather suspect that there is a tried and true option 3 of which I am unaware.

If there is, neither I nor most manufactures know of it. The real key to success is to think through all the possibilities for failure (primarily saturation) and alleviate them. From reading your post you are already thinking through details many don't.

[Tim]

1) Fiberglassing the plywood to the hull and covering the inside of the plywood with fiberglass. The idea being that if the fuel tank should ever spring a leak hopefully the diesel would be contained in the setee and not run into the deep bilge.

2) Leaving the plywood about a quarter of an inch proud of the fiberglass so that any water can easily run into the deep bilge. Since this is below the level of the cabin sole, this will not show. Unfortunately something like a pencil could also roll under the plywood into the deep bilge.

I'd go with option #1, partly for the potential fuel containment you mention (though that will probably never happen), but mostly because any opening between a storage locker and the bilge that allows nuisance water to drain out will also potentially allow bilge water to enter the locker when the boat heels or moves in a seaway. This is something you want to avoid.

Limbers make good sense in a lot of cases, but not if they provide a passage for bilge water into supposedly dry storage lockers. Do your best to keep your storage lockers isolated and dry. Water shouldn't get in there on its own; if it does, find out why and fix the problem.

[feetup]

I hope I'm not highjacking this thread, if so, tell me and I'll start a new one.
I noticed that the factory that built my boat sprayed the accessable areas of all the plywood with gelcoat, but through the cycles of expansion and contraction the gelcoat natually developed a network of cracks (generally following the grain of the surface ply) all over.
I understand that gelcoat is one of the poorer choices for sealing wood, but does thickened epoxy have the elasticity to move with the wood for the time span we hope to achieve in our interior cabinetry? It is such a chore to coat the plywood with epoxy anyway, and since the resin is the greater part of the cost incured, would it not be a better choice to give it a layer of cloth to prevent the hairline cracks that are almost inevitable, and to double seal all the end grain? Is this just waisted effort?

Feetup[/i]

[suntreader]

I'm voting for option 1 as well. I had a previous boat with the settee front not running all the way to the hull, leaving a half inch or less gap for water to drain down (this was a molded hull liner rather than plywood.) The problem was the bilge was so shallow that the locker would get wet every time we sailed upwind!

In a glass boat you don't have to worry as much about water having a path to the bilge from every locker, a settee locker should be pretty easy to keep dry, probably more so without moist air coming up from the bilge through a drain hole. As for a fuel tank in there, even if it does leak you don't want it leaking into the bilge, having it trapped in the settee locker is a better option.

You probably don't need to glass the entire settee front, just tab it in and give it three coats of paint.

David

[Quetzalsailor]

John, I, of course, have the same problems with delamination at the bottom edges of the plywood. Not as badly affected as yours. I intend to relaminate the few bad places and coat out the lower couple inches in epoxy in the concealed areas.

I bought a slug of Makore veneer for repair work. Unfortunately, it's about 1/42" (or more likely the metric equivalent). Miserably thin for amateur's work! 1/32" is do-able; 1/16" is relatively easy.

I reused the faux-Teak fir plywood settee front on the Morgan 27. It was rotted, but not delaminated. After thorough drying, I soaked all the WEST epoxy that it would take into the edges, built it back up with filled epoxy, tabbed it in, and painted all the faux-Teak in the boat. No further deterioration in the ensuing 10 years that we had the boat.