Replacing V-berth platform

[jaysweet]

Several years ago, I had a leak in the anchor locker, and the drips somehow migrated to where the soft hull liner met the V-berth platform. This platform (the place where the cushions sit) is/was made of plywood with a brown layer laminated on both sides (linoleum?), and the leak caused the plywood to completely delaminate.

So: I"m replacing the whole platform with some 1/2" red oak plywood, which I will coat with 2 layers of epoxy to waterproof it. My question is this: should I re-use the 4 old hatch covers vs. using the plywood that I cut out of the holes as the new hatch covers? To explain: the old hatch covers have a flange on all edges, so they actually sit 1/2 on top of the platform, maybe 1/4" proud. The new wood covers would be cut-outs, so I'd have to use a plywood strip glued/screwed along the joint underneath to keep the covers from falling through. My only worry is whether this strip will be strong enough to hold the weight of a person. I'd actually prefer to use the new wood covers, since it would look better and the entire platform would be flush, but it's got to hold the weight.

 

[Tally Ho]

I would use your cutouts and glue/screw some backing strips under the deck to keep the lids from falling in. Your could just do the 4 corners on a diagonal.

Greg

 

[dLj]

I prefer the smooth top. So I agree with Greg.

If you are worried the glue won't hold, use flat head bolts with nut and washer on the underside. Glued and bolted won't go anywhere.

dj

 

[kloudie1]

The original lids on my old h34 have a *cleat* under the top platform. Essentially a half inch by two inch piece of hardwood screwed in from the top so that half of the hardwood supports the lid. The lid is flush on top. There are cleats on the long sides of the opening . The settees in the cabin are done that way and are fine for supporting folks.

 

[jaysweet]

I guess I'm leaning 90% towards new wood covers with a backing strip. From what I've read, epoxy and wood glue are about equally strong, but I'm already going to coat the whole thing with epoxy, and it's waterproof, so I'll probably go with epoxy. Anyone know if plain epoxy vs. thickened epoxy makes a difference? I'm using West System. I've never messed with adding a thickener.

Flat-head bolts are a good idea. Definitely stronger than wood screws, the only downside being that they're visible. But this whole area is basically hidden under cushions 95% of the time. I do want it to look good, regardless, b/c... it's not a small amount of work, and sailing is largely about aesthetics.

Thanks.

 

[jaysweet]

The original lids on my old h34 have a *cleat* under the top platform. Essentially a half inch by two inch piece of hardwood screwed in from the top so that half of the hardwood supports the lid. The lid is flush on top. There are cleats on the long sides of the opening . The settees in the cabin are done that way and are fine for supporting folks.

That's good input: thanks. The "supporting weight" issue is my only worry.

 

[kloudie1]

Here is a picture of the cleats that have the lids flush with the surface.. I noted that the cleats were on two sides, but I see in the picture that all four sides of the opening have the backing plates. The edges of the plates are rounded off (bull nosed) so stuff doesn't snag .. I weigh around 240 pounds and this has not failed in the 40 years that the old girl has been around .

 

[JBP-PA]

Anyone know if plain epoxy vs. thickened epoxy makes a difference? I'm using West System. I've never messed with adding a thickener.

For waterproofing, you want unthickened epoxy. As thin as possible, so warm up the resin and wood to about 75-80 F and work fast. You want penetration into the wood. You can also buy penetrating epoxy designed just for this.

To glue wood together, you want thickened epoxy. Fumed silica aka Cabosil, I don't know the WEST number. This helps it fill the gaps caused by wood grain. About mayonnaise/ketchup to creamy peanut butter consistency. You can also buy pre-thickened expoxy, such as six10 or Thixo.

 

[dLj]

Since you are using plywood, using glue that glue adheres to the surface layers of the plywood. It likely is fine for the Vee berth covers. But if you are worried about long term strength, adding in through bolts will remove that worry.

I have a bench at my chart table that gets a lot of very rough usage. It's a seat, bed, more. I was thrown onto it in a storm and sheared those supports of the cover. I replaced them with solid wood, glued and through bolted and no more problems. The bolt heads are not very noticable plus there is the cushion on top unless accessing the compartment. I don't find them out of place when exposed.

dj

p.s. I'm not a little guy... I'm north of 200 pounds...

 

[jaysweet]

Here is a picture of the cleats that have the lids flush with the surface.. I noted that the cleats were on two sides, but I see in the picture that all four sides of the opening have the backing plates. The edges of the plates are rounded off (bull nosed) so stuff doesn't snag .. I weigh around 240 pounds and this has not failed in the 40 years that the old girl has been around .
View attachment 231681

Thanks. I think I'll use 2" of 1/2" plywood with bolts and epoxy. Should work well.

 

[jaysweet]

For waterproofing, you want unthickened epoxy. As thin as possible, so warm up the rain and wood to about 75-80 F and work fast. You want penetration into the wood. You can also buy penetrating epoxy designed just for this.

To glue wood together, you want thickened epoxy. Fumed silica aka Cabosil, I don't know the WEST number. This helps it fill the gaps caused by wood grain. About mayonnaise/ketchup to creamy peanut butter consistency. You can also buy pre-thickened expoxy, such as six10 or Thixo.

I did some research already about waterproofing, and plan to use regular resin plus the 207 special clear hardener. I was really asking about whether or not to thicken it for gluing the cleats/strips, and I'm seeing that you advise thickening. I'll probably buy some sort of additive for this. Thanks!

 

[dLj]

I did some research already about waterproofing, and plan to use regular resin plus the 207 special clear hardener. I was really asking about whether or not to thicken it for gluing the cleats/strips, and I'm seeing that you advise thickening. I'll probably buy some sort of additive for this. Thanks!

The standard method (as far as I'm aware) is to use the un-thickened resin on the gluing surfaces, apply the thickened mixture between the two surfaces after that, then clamp and go...

dj

 

[Project_Mayhem]

I would use the cutout but put strips on the bottom of the main piece that go all the way across the hole. Much stronger this way. Flush is the way to go. I can notice small imperfections under my hybrid mattress at home

 

[jaysweet]

Thanks for the replies. I did lots of work over the weekend, mainly trimming the 3 sections to fit in the boat: the forward piece is in the picture above, and the old aft piece is the last of 4 pictures. As you may be able to see, the aft piece (the brown colored thing with 3 hatches and one filler section), I had to cut in 2 to get it out of the boat. Clearly, they installed it before the deck went on. So I have 3 sections to fit, and a few more access hatches to cut. It should all go smoothly, but it's pretty fiddly work to cut out the access hatches when you want both the larger piece and the access hatch to be perfect. I've got a system down now, though, so it's going ok.

On other news, I probably need to get the bottom painted and launch before finishing all of this, since I'm paying for dry storage by the day. Also, I can sail and still use the aft cabin while working on the v-berth, even if the finish work takes a few weeks.

 

[niceshoes6]

Jay did you find a similar top laminate to the original? I'm in the same boat as you with a leaky anchor locker and rotted V-berth. The only thing I could find if the underside backer product. That's this. 909 Surfaces Brown Backer Sheet

 

[jaysweet]

Jay did you find a similar top laminate to the original? I'm in the same boat as you with a leaky anchor locker and rotted V-berth. The only thing I could find if the underside backer product. That's this. 909 Surfaces Brown Backer Sheet

No, I'm just going to go with water-based stain and 2 coats of epoxy (maybe more on the edges). I think/hope that the natural wood will look better than the brown stuff on the rare occasions when the cushions aren't on top of it.

BTW: it does look like the brown laminate was extra glued on top of 1/2" plywood, as the original was actually thicker than normal plywood. (Of course, 1/2" plywood isn't really 0.5 inches, but whatever: I measured both with calipers.) I considered going with thicker plywood, but 5/8" seemed overkill. I decided it didn't really matter, as the surface has good support from the vertical bulkheads and the tabbed-in support along the hull, and I'll probably put in some extra bracing in a few places that wasn't there originally.