glue

[KEVMAR]

I am going to replace some rotten plywood in the aft cabin bulk head, which type of glue should I use to adhere the plywood to the fiberglass bulk head . thank you

 

[O C Diver]

If you're not ever going to remove it, construction adhesive in a caulk tube such as Liquid Nails would be my choice.

Ted

 

[Lou_tribal]

I am going to replace some rotten plywood in the aft cabin bulk head, which type of glue should I use to adhere the plywood to the fiberglass bulk head . thank you

Epoxy

 

[aboatman]

I'm going with the construction adhesive unless you post more details or a reason it wouldn't be the best choice.

If you go to the home enter, you will find about a dozen different brands and types of construction adhesive. Read the labels and decide which would be best for your project. Water resistant or "outdoor" would be good things to look for.

 

[Larry M]

I’ve always glassed in plywood to fiberglass using either polyester resin or epoxy.

Did you just cut out a piece/small section or do you need to tab a piece in?

I don’t mean to offend you but I’ve never heard of using construction adhesive as a proper fix on a boat.

 

[twistedtree]

If it's a repair to a bulkhead then presumably you want to restore as much of it's structural integrity as possible. I think that calls for epoxy and glassing it in as thoroughly as possible.

 

[dhmeissner]

 

[O C Diver]

I am going to replace some rotten plywood in the aft cabin bulk head, which type of glue should I use to adhere the plywood to the fiberglass bulk head . thank you

Ok, I may be misunderstanding this, but this sounds the plywood is the final surface and not being glassed over it. If the plywood will be covered with fiberglass and is structural, I would use West System thickened with their white bonding powder.

Ted

 

[Simi 60]

Why and how did it rot.
Fix that problem first.
If its a structural repair use epoxy
If cosmetic liquid nails or sika or epoxy

 

[FF]

Epoxy is a glue ,

polly resin is for building GRP boats .

It sticks to wood a bit better than tape, but is not structural.

Stuck on plywood outside with some glass it can make the ply more water resistant ,

but any/every penetration is a danger and needs to be re bedded on a sked..

 

[KEVMAR]

I am in the process of replacing the aft window that had been leaking for many years .and the plywood was rotten and soaked if I could figure how to post a pic I would .,,

 

[aboatman]

It seems this is a case of "If you want the right answer you have to ask the right question."

If this is structural, not cosmetic or decorative, I would change my answer to epoxy. For paneling or such, construction adhesive.

 

[kenk]

To post a picture click on the ( Post Reply ) button that will bring up another screen here you should see what looks like a paper clip, click on the paper clip than (Choose file )
now you can select the picture off your computer.

You can not post pictures if you do a ( Quick Reply ) you have to click on (Post Reply)

 

[KEVMAR]

I am trying to be specific as I can .. excuse me

 

[KEVMAR]

It is not structural just filling in where the rotten wet wood was removed

 

[aboatman]

If you're gluing wood to wood, Gorilla Glue is a very good choice. Waterproof carpenter's glue would also work.

Gorilla Glue expands as it cures so keep that in mind and clamp or screw the parts together.

 

[psneeld]

I would tend to say that repair is somewhat structural.

On my boat I used epoxy and extetior ply to fill in where rotten ply came out.

Then used liquid nails to put up tongue and groove bead board as the finished surface.

Now I am not saying liquid nails is not structural as I believe it meets some building requirements when using 2 boards together to make a span.... but would have to double check that. Either way, I would still use epoxy for glueing in the ply as the butt and scarfed joints will be stronger.

 

[KEVMAR]

I’m gluing wood to fiberglass marine grade plywood

 

[DHeckrotte]

Looks like the inside of the house side with the port removed. I'd expect to see polyester/'glass - wood - exterior polyester/'glass as the structure on that largish flat area. Is that what you can see the edge of in the port opening? Is that wood core rotten too? Or is the exterior of the house polyester/'glass? If you've really got an intact/not-rotten-cored-structure then what was the removed rotten wood for? Perhaps solely for affixing the interior finish surface?

My recommendations/several answers:

1, If you have exposed core around the port opening, then clean the remains of the sealants and glues from the edges of 'glass and core, scoop out any rotted core, make sure it's dry and clean, coat with neat epoxy and fill gaps with thickened epoxy.

2, If you have solid 'glass and the rotted wood was simply for providing something to affix the interior finish then any of the suggestions above for construction adhesive or epoxy should be at least as good as the original construction which was good enough until the leak caused rot. However, I would coat out the new wood with epoxy and glue it to the 'glass with thickened epoxy. I would also coat the interior surface of the finish plywood with epoxy. I soooo hate to fix things twice!

3, If you have a 'glass exterior that was intended to be stiffened by the interior rotted plywood, which you could surmise by how thoroughly it was stuck on to the 'glass with polyester, then replace it with plywood coated out with epoxy and glued on with thickened epoxy. Polyester really does not bond wood to 'glass very well.

I've done this sort of work on our sailboats.

 

[Comodave]

+1 on the epoxy

 

[psneeld]

if like my Albin....no core....just plywood with oaper thin glass on the outside....

thus my sorta ssructural repair comnent....

 

[FF]

"It is not structural just filling in where the rotten wet wood was removed."

The rotten plywood Was structural, even if there is 3/8 GRP on the outside , the ply was to stiffen the area .

 

[twistedtree]

I would repair with the assumption it is structural, and use epoxy. It can do no harm, where assuming it is not structural, and later finding you were wrong would be a real PITA.

 

[TugYacht_33]

you cant fill in gaps with liquid nails
and anything surrounding a door or window should be treated as structural, even though it may not be, treat it as such and you will never have to worry about messing with it again....
i would go epoxy with any "glue" repair, i have seen liquid nails fail (the good stuff) due to moister and vibration over time

 

[JohnP]

Epoxy for gluing the plywood to the underlying fiberglass, also epoxy coat the plywood to seal it. Then I use PL premium for gluing interior panels to the plywood core. Never had any failure of a PL premium construction glue in my past or present boat. JohnP