Glassing Hull-to-Deck Joint

[Captin_Kirk]

I decided today that because I am striping the deck of all hardware and wood trim including the toerail that I should spend the time and redo the hull to deck joint. I searched the forum and found that most think it best to glass the joint instead of using a sealant like 3m 5200.

My question is the best way to do this?

1) I figured I would clean the joint of existing sealant
2) open the joint and apply some epoxy resin and re screw/bolt it down.
3) fair the top edge into the hull side a bit so it is flatter.
4) cut strips of glass cloth about 1" thick and apply to the joint. My toerail is about 2 inches thick so if the job is not 100 % perfect this will cover it)
5) Drill over-sized hole in all existing bolt and screw holes and fill with epoxy
6) paint entire deck while all hardware off,
7) re-bed toerail and all hardware using 3m 101.

Does this sound like the best way to ensure the seam is watertight? Any suggestion would be greatly appreciated.

[Charlie]

have you looked at the Islander websites? my deck to hull joint is bedded with a non curing sealant. It doesn't leak.

[Captin_Kirk]

I have a leaks on my boat now, I am not sure if it is from there or the bolt holes though. I just thought, if I re-bed everything and leave the joint alone only to find out it is leaking, I would be pretty mad at myself for not fixing it when I had the chance.

What is the address of the islander site you are referring to?

[s/v Jedi]

You don't have to cut fiberglass... buy it in tape-form on a roll.

cheers,
Nick.

[rbhb2]

You will never be able to adequately clean the joint (overlap) enough to get a good bond by injecting thickened epoxy. Just leave the old sealant in place and glass over the joint.

[delmarrey]

Originally Posted by rbhb2

You will never be able to adequately clean the joint (overlap) enough to get a good bond by injecting thickened epoxy. Just leave the old sealant in place and glass over the joint.

Ditto!

And just leave in the old bolts and glass over them. If they stick up too far, get some flat head screws and flat washers with the hole slightly smaller then the head of the screw. Glass over that and fair in and glass again over the flat surface.

And epoxy in the screws to keep them from working with the hull twist. This is what I plan for mine fairly soon, maybe this summer.

[Joli]

Well, if you're going to do all that then you may as well go ahead and remove the toe rail, cabinetry, and headliners to get to the joint. It's going to be a long hard slog and you will not be able to glass the hull/deck flange where the bulkheads stand. Clean the joint with a 4 inch grinder fitted with a chicken plucker, vacuum it up and wipe it down so it's clean. Mix a slurry of poly resin and cabofil so it stays in place and then work in a 6 inch tape. I would work in 3-4 foot sections. Note: when you pull the toe rail you should re-bolt the hull deck flange ever ~ 4 foot or the hull may hog! When you work your way down the flange joint do not glass the bolts you will want to take those out later. After you have glassed this joint remove the bolts and grind and glass another layer overlapping your previous layer. How many layers? Depending on the cloth weight maybe 4 to 6? And you should do a light grind between each layer.

Big job but the boat will then be very stiff and dry when done. This is hard work since it is dirty, there is limited room and you are working upside down.

Supplies can be purchased here: Fibre Glast Developments : Carbon Fiber : Fiberglass : Resin : Kevlar : Epoxy : Polyester : Gel Coats : Fillers

As an aside. Our hull deck joint is glassed. The boat has a ~6" hull/deck flange, it doesn't leak but it was built this way originally.

Good luck,

Joli

[Charlie]

I haven't looked for a specific Islander 30 site but here is the I36 site.

[Fishman_Tx]

G/Flex
G/flex Epoxies
and heres a demo

YouTube - WEST System G/flex Epoxy Howto

[s/v Jedi]

I just started using G/Flex and like it very much for some of my projects. I bought the tubes that are mixed 1:1 for a paste.

cheers,
Nick.

[Joli]

I like epoxy but for a big job like this I would use polyester. It's cheap, quick, can be thickened easily to work upside down and the rest of the boat is built out of the stuff.

We met a guy who was redoing his deck with epoxy and foam. He had been working on it for years and had spent tens of thousands. When we re-did the transom we used balsa and polyester. I removed about 8 square foot of wet balsa and replaced it, faired it, and painted it in two weekends for about $150. He came over and told me I was doing a lousy job not using epoxy and foam and it could get wet again.

Maybe he's right, I don't know, but we went sailing that summer, he didn't, and it is still dry today, 6 years later.

[s/v Jedi]

Hey Joli... I think the only argument for polyester is that it is cheaper than epoxy. All the rest is just as good or better with epoxy.... but I guess you know all that.

For cruising sailboats I like balsa better than foam. Balsa you only need to keep dry... foam you need to keep dry and cool. I'd rather use a modern honeycomb than foam.

cheers,
Nick.

[Joli]

Sure, epoxy has better adhesion, better mechanicals, and on and on but its also 5 times the price. I have a hard time getting past that if I'm fixing a 30 year old boat that is worth $8k?

[s/v Jedi]

Indeed, cost is a valid reason for using polyester. I think it's time to ban polyester for new build boats though... (go to vinylester at minimum).

cheers,
Nick.

[delmarrey]

Originally Posted by Joli

Sure, epoxy has better adhesion, better mechanicals, and on and on but its also 5 times the price. I have a hard time getting past that if I'm fixing a 30 year old boat that is worth $8k?

Also, Epoxy takes a full day to cure enough to sand & fair. Polyester cures enough within a couple hours to work.

I use both quite often. Anything below the water line or structural is definatly epoxy. But for general work polyester is great. Although, interior work I prefer epoxy due to the fumes. I've known of a couple boats that have burned due to the ignorance of the user with polyester.

And the two do stick together unlike what some may say. I've experimented and they bond to each other quite well, even un-preped.