Wood / Fibreglass adhesive

[ArranP]

This photo is of the ceiling on my boat it shows the wood frame that holds the ceiling panel has come free from the fibreglass deck.

Is this adhesive regular silicone or "no nails" ?

https://photos.app.goo.gl/5RTCvcFhKMPjZTgU7

[Franziska]

You are referring to the part which is permanent glued to the deck, correct?Dont use Silicone. My first choice would be epoxy, my second 3M 5200.
In any case, clean and sand the two surfaces to be glued properly and whipe with Acetone before glueing.

Little background on this.

Silicone has no use on a boat (if you ever get a spec of it under a sanding disk and want to paint later, you'll know why).
There are two very specific exceptions. High temperature Silicone as temporary gasket repair material and acid free Silicone on Sta Loc type terminals.

Tons of good marine caulking materials around, most are polyurethane based.
Some of them are even formulated to act as structural glue. 3M 5200 would be one of those.

[Chotu]

Agree with Franziska.

But also it’s not a good bond area. It’s too small.

No matter what you use, cut a little bit off the top of the piece that came loose. Bond a larger piece of wood flat to the fiberglass ceiling.
Then screw that piece that came loose to the larger piece of wood you bonded to the ceiling.
It will never have the problem again, even if you use “no nails.”

I’m assuming you’re maybe not in Bangkok and it is difficult to find the right marine product?

[ArranP]

Originally Posted by Chotu

Agree with Franziska.

But also it’s not a good bond area. It’s too small.

No matter what you use, cut a little bit off the top of the piece that came loose. Bond a larger piece of wood flat to the fiberglass ceiling.
Then screw that piece that came loose to the larger piece of wood you bonded to the ceiling.
It will never have the problem again, even if you use “no nails.”

I’m assuming you’re maybe not in Bangkok and it is difficult to find the right marine product?

Koh Lanta, there are plenty construction shops.

[Chotu]

Originally Posted by ArranP

Koh Lanta, there are plenty construction shops.

Good! No matter what you use, not silicone, just make a larger bond area and it will work.

[ArranP]

Originally Posted by Chotu

Good! No matter what you use, not silicone, just make a larger bond area and it will work.

So can use "no nails" ?

[sailingharry]

Originally Posted by ArranP

So can use "no nails" ?

The picture didn't come through for me, so I can't see the details. But on numerous occasions I have used construction adhesive to glue wood material to the hull. Never anything that I would call structural or high load, but lots of small stuff. Most recently, a backer board to hold my solar controller. Cheap, easy to work with, plenty strong for many applications. And it likes both fiberglass and wood.

[Chotu]

You can, if you can’t get plexus or 3m 5200. I have used the most recent version of “no nails”, called PL Max Premium here in the USA. I used it to put a piece of wood on a horizontal surface and hold my hydraulic autopilot pump in place.

It holds the frames for my windows in place.

It works great. You just need a large bond area. That is why it failed originally. Because lagoon did not do a good job with that. They tried to bond the edge of that went to a very small area.

[ArranP]

Originally Posted by Chotu

You can, if you can’t get plexus or 3m 5200. I have used the most recent version of “no nails”, called PL Max Premium here in the USA. I used it to put a piece of wood on a horizontal surface and hold my hydraulic autopilot pump in place.

It holds the frames for my windows in place.

It works great. You just need a large bond area. That is why it failed originally. Because lagoon did not do a good job with that. They tried to bond the edge of that went to a very small area.

Thanks.

But I guess that the silicone can be used on patching the seal in between the the window panes and the deck ?

[Tin Tin]

No Nails, Liquid nails - whatever, get the specs for the shear and tensile strength.
3M marine adhesive sealant 5200 has shear strength of around 500+psi on wood and 360psi on fiberglass. Liquid nails is around 300-400psi depending on brand. https://multimedia.3m.com/mws/media/...-tech-data.pdf


Plexus a very strong glue used for this sort of joining has a shear strength of around 2000psi. Not cheap.

[Bill O]

That piece looked like an add-on and not original construction.

As mentioned by Chotu, maybe more surface area will help the adhesive stick better. Would also try to clean and rough up the f/g surface before bonding.

[Chotu]

Correction on my post. I used PL Premium “no nails” to glue the mounting board for my hydraulic autohelm to a *vertical* surface.

[c.K.]

Originally Posted by sailingharry

The picture didn't come through for me, so I can't see the details. But on numerous occasions I have used construction adhesive to glue wood material to the hull. Never anything that I would call structural or high load, but lots of small stuff. Most recently, a backer board to hold my solar controller. Cheap, easy to work with, plenty strong for many applications. And it likes both fiberglass and wood.

no nails is polyurethane, and yes you can even glue styro foam with that material