Hull / Deck Joint

[Dave]

The rainy season has arrived in Seattle and the small hull/deck leak I had on 357 in the spring is a bit worse -- dampening the starboard book shelf when it rains.
The manual suggests removing the rubrail and recaulking or epoxying the joint, then re-fastening the rubrail.
I'd like to use epoxy filler on the joint, fair it out, and paint the hull (which I intend to do anyway).
I don't think the rubrail is particularly attractive or useful.
Is there any reason I can't just fill the joint and be done with it? Or does the joint flex so that I'd be left with cracks?
I have a teak caprail so that the joint is through-bolted -- I can't imagine any flexing...
Thoughts?

Dave G

[commanderpete]

Have you taken off the rubrail in that area?

When I took mine off, the hull/deck joint did not look like the picture in the manual. There was no gap and I didnt see any evidence of old caulking or "rigid plastic filler." The joint was smooth.

I agree that the stainless steel rubrail is pretty whimpy. Worse than that, if the rubrail is not properly sealed to the hull, water will get trapped behind it or enter through the screw holes.

As for me, I wouldnt want to be without a rubrail. In fact, I'm going to install a stout teak rubrial so that I can menace the various docks and pilings in my area with greater impunity.

But, I digress. If you haven't done so already, I would check to see what the hull/deck joint actually looks like on your boat.

If there is a gap and you're going to use epoxy, you're probably going to have to thicken the epoxy with silica or the like.

Have you actually traced the source of that pesky leak? Is it a rubrail screw hole?

Cheers,

Peter

[Ed Ekers]

On Pathfinder (#77) we had a deck joint that you could jam your fingers though. Needless to say more than just a small leak. After thinking of different options our solution ended up doing a fiberglass strip over the length of the joint. I was told by some local glass people that it was not wise to mix a resin surfaces with epoxy. They suggest that I use resin to set the strips of glass.

So we removed the rub rail cleaned and ground down the joint to glass. Then laid in strips of fiberglass, more sanding and more sanding to fair it out and then shot gel coat.

All this was done about ten years ago and to date no problems at all. By the way we did replace the rub rail just in case we came in to contact with Commander Pete.

[Mike Goodwin]

My hull/deck joint looks like Pete's , and I also plan on a 2 piece teak rubrail with a stainless cap.
Pete, we can play 'bumper cars' , or better yet sandwich some poor sot between us , the old squeeze play .

Mike

[Dave]

Ed,
I'm not sure what you mean when you say that you were told "it was not wise to mix a resin surfaces with epoxy. They suggest that I use resin to set the strips of glass."
Were you told not to use epoxy resin on a polyester resin hull? I've used West Systems epoxy on a number of polyester resin hulls and my understanding is that they are compatible.
Did you use cloth rather than resin thickened with filler in the joint because you were concerned that filler wouldn't be strong enough?
Does this joint "open up" due to flexing?
Sorry to ask so many questions, but I really would like to do this right.
Thanks to all for your help with this.
--Dave

[Mike Goodwin]

Most 'modern' boats use a product not unlike 3M-5200 or Sikaflex in the hull to deck joint .
Allows some flex, but wont let go .
When I add my wooden rub rail , it will be bedded in a similar product which will fill the joint , and every 3rd fastener will be a thru-bolt .

Ed may be talking about not glassing to gelcoat , which is a no-no with epoxy or poly . I would use vinylester resin instead of epoxy , lots cheaper, easier and just as strong .
I have gone thru 100's & 100's of gallions of resins , epoxy ,poly & vinyl , and West System is more hype than quality . System 3 is just as good and cheaper as are many other resins , but if that is all you can get , use it .
I prefer some no-name brands , @ $32 per gal.

[Ed Ekers]

Dave I am not sure I know all that I know about the different types of agents used with fiberglass. Maybe Mike G is explaining it better than I could.

But to answer a couple of your questions, I think the joint opens up due to the joint compound breaking down and exposing large voids. I choose to use strips of glass because I wanted to assure a seal and it was a lot cheaper. I also think in the end it was easier as well.

I do recall having a discussion on what grade of fiberglass to use but do not recall what the final answer was. But I know that some glass was better for what I was doing than others.

I also agree with Mike that there is a number of products/methods to use that cost a lot less than the West System.

[Mike Goodwin]

For doing the hull/deck joint, a biaxel fiberglass tape is the ticket . With regular tape only half the fibers cross the joint , with biaxel tape , all the fibers cross the joint and is over twice as strong , so you can use less material .

Regular Tape ===========

Biaxel tape XXXXXXXXXXXX

[Dave]

Thanks all for your help. I'm taking the rubrail off tomorrow and will have a look at the joint.

[ebb]

my 2 cents here .. No deck/hull joint should ever flex - it should be as rigid as the keel, whats to flex?, it's a rightangle joint. Rubber is used by factories because it comes out of a tube and is easier than wetting in a couple layers of frp like Pearson did with Ariel. The amazing thing is that it's a 1/8" butt join into which they drove 100 screws. preopec polyester was something else!
For the rest of the change .. I'm definitely going with the Ekers tape outside fix on the joiunt (I've already been lamming glass to the inside). But I'm also going to fill the inside cove of the toerail with mahogany strips and epoxy to create a flat to take bolts for a toerail and the stanchions. I won't have a zipper there anymore!

[commanderpete]

Dave,

You mentioned that you have a "teak caprail." I'm green with envy. That must look nice. Do you have any pictures?

Just the thought of another 50 feet of wood to varnish gets my
heart all aflutter.

Are the Genoa tracks mounted on top?

Ebb,

I'm interested in the interior lamination you did at the hull/deck joint. What type of cloth/tape did you use? Do you have to sand off all of the paint first? Will the cloth stick upside down while it cures?

Cheers,

Peter

[ebb]

don't know much about epoxy
don't know much about sanity ...
Peter. 338 is mostly nude inside, just couldn't stand the funky cover-all-yer-sins spraypaint job especially that splatter paint with pastel color droplets in the cabin. SO WE GROUND IT ALL OFF. Up inside the toe rail too. (and under the cockpit)
You paint on your regular 2:1 epoxy. {been using TAP which doesn't blush even when slow curing). Wait til it gets tacky, your finger doesn't get wet, press on the fabric, it will cling nicely. Finish off with a fresh batch with silica so it doesn't run. Fabric WILL go clear and it ends up smooth too using vigorous bristle brush and latex covered finger. A plus: using the thixotropic silica allows you to push the goop into the weave after it's set up where the cloth spanned what you didn'i grind smooth in prep, you can end up with no obvious voids.

[ebb]

sorry Peter, been using regular 8oz fiberglass. I have a 12" wide roll which I cut in half (right, no not the whole roll). In the cabin I put the selvage along the liner. So I had to listen to my languge on the down part on the hull where it unraveled. Should use tape, and of course if you insist on doing it inside you need only to do from the top of the cove down say 3" I'm sure the EdEkers outside fix is enough. My middle name is overkill, I'm also going to add a mahogany toerail to 338 which is why this area needs strength.

[Dave]

Peter,
The teak caprail does look very good and adds another inch to the rail so that screwdrivers and small parts have to bounce that much higher before they go overboard. I've seen the caprail on most of the Ariels here in the Northwest. Pictures? Can we attach pictures on these posts?
Because of the caprail, I won't be covering the hull / deck joint with teak -- it would just be too much. I'm filling and fairing the joint and painting the hull. Any docks I encounter are far below the existing rubrail anyway, and there is almost no defense against a determined powerboat owner.
The genoa tracks are inboard of the rail on the deck.
--Dave

[commanderpete]

Dave,

It looks like this website is capable of posting pictures, but these technological innovations are beyond me.

I think you'll eventually find that even the lightest touch on a dock or piling can leave a smear of creosote. This can be difficult to remove from one-part paint.

I'm putting on a solid teak rubrail for two other reasons.

I'll be starting my racing career next season. I figure a proper rubrail will further frighten experienced racers like Ed from trying to get too close.

Over the years, I've also seen the results of several boats that broke free during a storm and were bashed unmercifully against a dock. Those with a proper rubrail had it battered, but avoided severe hull damage.

That caprail does sound useful. My single season record for losing tools overboard is two screwdrivers and one wrench.