Attaching things to fibreglass

[MickP]

Hello,
Very basic question i'm afraid....I have bought myself a circuit breaker to sit between the shore power inlet and the AC distribution panel. I want to put it next to the inlet, which means in the starboard cockpit locker. The breaker sits in an enclosure which has mounting holes, but the fibreglass of the locker wall is not thick enough to screw to. I guess i need to screw the enclsoure to a backing plate and then stick the backing plate to the fibreglass, but is this the best way? If so, what material should the backing plate be, and what should i use to stick it to the fibreglass?
thanks very much

 

[Merlin Clark]

You could through bolt it (washer and nut on other side) if you can get access to the other side of that bulkhead.
If you can't get to the other side or don't want nuts and washers showing, plywood would work for mounting it and a 2 part epoxy glue kit or some "Liquid Nail" from the hardware store will hold the plywood to the bulkhead. I'd get the fast cure version or tape/brace/prop the wood in place while waiting for the product to cure.

 

[Charlie Jones s/v Tehani]

Epoxied Plywood backing, and this is a perfect application for 5200.

Oh- and I've had a hook in my shower at home, stuck on with 5200 6 years ago- still there- get's showered on daily.

 

[Bill Roosa]

I'm having trouble understanding how the FG can be "too thin to screw to"
I'm thinking you are using the wrong screws. FG is much stronger than you would think. My dingy has 1-2 oz deck cloth (1 layer) and we beached it on sharp rocks, riprap,..... and after 7 years it was still holding its own.

 

[IStream]

I've used Ipe wood very successfully as an alternative to plywood and it saves you from having to use epoxy. It's as durable as teak but far more affordable. Make sure you drill pilot holes for your screws or, like teak, it can split. Some 5200 on the back and it won't go anywhere.

 

[MickP]

Thanks all. Looks like i will go the plywood/5200 route.

Bill, when i say too thin, i mean the wall i will be screwing to is the cockpit wall of the locker. I don't know exactly how thick it is, but i don't want the screw tips to be sticking out into the cockpit.

 

[Winkfish]

Thanks all. Looks like i will go the plywood/5200 route.

Bill, when i say too thin, i mean the wall i will be screwing to is the cockpit wall of the locker. I don't know exactly how thick it is, but i don't want the screw tips to be sticking out into the cockpit.

Could you not place it on a side of the locker where the screws would not go into the cockpit?

 

[MickP]

Winkfish,
Not really. I want to position it where i can reach it easily if nec, and not too far off the route to the AC dist panel

 

[woodster]

Thanks all. Looks like i will go the plywood/5200 route.

Bill, when i say too thin, i mean the wall i will be screwing to is the cockpit wall of the locker. I don't know exactly how thick it is, but i don't want the screw tips to be sticking out into the cockpit.

fasten it with ss Phillips head pan head screws on the out side and use nuts washers and lock washers on the inside that should do it for you ...no glue ,epoxy and no mess.......just use some butyl tape to seal the penetrations fro the out side and you should be good to go......

regards

woody

 

[caguy]

Why not just bond the switch to the FG using 5200 without screws.

 

[kito]

Just me but I try to avoid any holes that would be exposed to the exterior. The exterior plywood/5200 seems like what I would do. That way it could be removed with no holes to fill....in case the next owner has other ideas. I wouldn't bother coating the exterior grade plywood with epoxy either.

 

[Stu Jackson]

Satan's Glue

Screw it in from the outside, so only the screw heads are in the cockpit. Use finishing washers. Don't waste your $$ on 5200.

Not only is it SATAN'S GLUE, you'll only use a small amount of it and once opened it won't last more than a day or so, so it won't be useful to you ever again.

Do a search on Satan's Glue and you'll find out much more. Doesn't belong on a boat, except for rare, very rare, instances.

 

[MickP]

Well, i'm glad that's cleared up then. Maybe i'll just use duck tape

 

[Charlie Jones s/v Tehani]

Screw it in from the outside, so only the screw heads are in the cockpit. Use finishing washers. Don't waste your $$ on 5200.

Not only is it SATAN'S GLUE, you'll only use a small amount of it and once opened it won't last more than a day or so, so it won't be useful to you ever again.

Do a search on Satan's Glue and you'll find out much more. Doesn't belong on a boat, except for rare, very rare, instances.

Wrong on the life span. Throw it into the vegetable crisper of your frig (in a baggie) and it'll be good to go for several years. I've kept opened tubes and caulking tubes for up to 2 years like that. And you can buy very small tubes for not a lot.

And yeah- it's tenacious- that's what it's SUPPOSED to be. Used in the correct place, it's great stuff. It's designed for stuff that isn't gonna have to come off. Used as a bedding under hardware, it sucks. Don't knock it if you use it wrong.

 

[kito]

I think people confuse 5200 as being a caulk.....it's a sealing adhesive that is waterproof and designed for permanent installations. Would work attaching a piece of plywood to fiberglass, just a few dabs is all that's needed. Most would apply a thick coat of the stuff to the plywood....

 

[Merlin Clark]

I think people confuse 5200 as being a caulk.....it's a sealing adhesive that is waterproof and designed for permanent installations. Would work attaching a piece of plywood to fiberglass, just a few dabs is all that's needed. Most would apply a thick coat of the stuff to the plywood....

That's what I would do and get it all over myself in the process!

 

[jibes138]

Why are you adding this extra circuit breaker? The AC panel should have a main breaker and then breakers for each circuit. The AC feed on the dock should also have a breaker. What purpose is this breaker supposed to serve?

 

[TENACITY CS36T]

Why are you adding this extra circuit breaker? The AC panel should have a main breaker and then breakers for each circuit. The AC feed on the dock should also have a breaker. What purpose is this breaker supposed to serve?

Likely to be within 10' of yachts power receptacle, to meet current regs.

 

[shemandr]

The hard part of the strictly adhesive approach is to stabilize whatever is adhered for the cure time whether it be epoxy, 5200, gorilla glue, or whatever. Without fasteners you will need to find some way of bracing the "Backing plate" for the cure time. Maybe you can wedge a piece of scrap to hold it there but I've found that when dealing with curved surfaces this can be difficult.
I would probably try to laminate several thin pieces, if the surface is curved, rather than scribe to fit. After the first thin laminate, small fasteners can be used to stabilize without penetrating the fiberglass into the cockpit. I hope this makes sense the way I've written it.

 

[woodster]

if you are going to glue it 5200 or what ever just get a C clamp and clamp it in place till it sets up.....but i would use fasteners and not mess with the glue thing ....

regards

woody