Hull to Deck Joint

J

JeffR

Member
exMember
Joined
Dec 7, 2005
RO Number
19718
Messages
277
There have been numerous discussions regarding hull to deck joints, most of them somehow leading to the inevitable Sea Ray is junk discussion because they glue and screw and they will fall apart if you go over a wave.

We're considering an upgrade for next season and have been looking at 5 - 6 year old boats from a very reputable production boat company...you could say they're the "Crown Jewel" (that's a little riddle for ya'). We've been on the boats, and recently took the plant tour which was very interesting.

Well, guess what...they glue and screw their deck joints, and are not afraid to tell you they are some of the strongest out there.

So what gives, are times-a-changin' and we should no longer consider them a top of the line builder and we get to bash them, too? Or, are we just not comfortable with some of this new technology?

As long as I'm warming up the can opener, I might as well also mention that their recent line of cruisers has fully cored hulls!
 
If the builder is who I think it is, I thought they only screwed the hull deck join in their smaller line. The bigger ones would get bolts, at least in certain areas.

As for coring, I thought they only cored their coupe line and not the fishy line, but I could be wrong. They use a vacuum bagging approach which has a good reputation in hull coring.

I think reputation has a lot to do with it, and that would be a factor in my decision. Does the builder have a rep to build well designed, strong, seaworthy boats? Yes. Does Sea Ray have a reputation of building strong seaworthy boat? Don't know.

That said, I would still rather have a boat not glued and screwed, nor cored.

Shel
 
Tiara has a screwed and glued deck joint? Imagine that. On all sizes of their boats?
 
I didn't ask about any specific size, but there were different sizes on the line when we were there and the response from the rep was that they are glued and screwed. When integrity of the joint was discussed, it was clear there were no concerns or they wouldn't do it.

Shel - you are correct about the coupes, that's why I mentioned their cruisers in the original post. Again, though, I didn't specifically ask about the comparison of the cruisers to the fishers. They were very open in discussing technology and showing the coring, etc, and it was very interesting.
 
Formula glues and bolts the hull to deck joint.
They use plexus, an irreversible adhesive that is indestructible, with bolts every 18 inches, or so.
Is there a better way to do it?
 
My '78 searay was pop riveted..and not very good.

Some years ago, at a boat show, I saw a northwest boat that had a seamless/bonded hull/deck joint. So, the truly solidly built boats do exist.
 
Hmmm... Sea Rays are junk? They must not be building them like they did in 1992. Mine is through bolted with steel plates and then glassed over top and bottom. I don't think they EVER wanted that joint to be opened or to leak. Also, mine has a solid hull. The only coring I have found is on the foredeck and side decks. She's tank that has handled 10' to 12' seas with some 14' in the mix like a champ. (not trying to sound tough - the boat handled that trip better than the crew did!)
 
Adhesive bonding/sealing is not new technology. It's been going on for forty plus years, with excellent results. The corvettes were bonded together with Goodyear's Pliobond adhesvies, auto seams and joints have been bonded together with vinyl plastisols, busses and trailers were bonded together with Amchem's Bondaflex adhesives, Aircraft fuel tanks were bonded together with PRC's polysulfides, helicopter blades and assemblies are bonded together with structural adhesives in autoclaves, truck/trailers were bonded together with Goodyear's and Hysols adhesives, etc, etc. Plus, there are too many additional industries to mention, where adhesive bonding has been used extensively with excellent results.

Most of the aforementioned adhesives are modified systems that provide both strength and flexibility. This can be done relatively easy. If I had my druthers, I would much prefer a boat where the deck joint was both bonded and screwed together.

Bob
 
I had HUGE hull to deck leak problems in my Regal 2465. I ended up pulling out as much of the caulk as I could (where there was some) and filling the entire joint with 5200. It was my first try at a job like that and while not the prettiest job, it was successful for what it was intended to do.

I believe Fountain glasses in the entire seam making the whole boat one monocoque unit.
 
quote:
Originally posted by GSENT

Formula glues and bolts the hull to deck joint.
They use plexus, an irreversible adhesive that is indestructible, with bolts every 18 inches, or so.
Is there a better way to do it?

Click to expand...
Gary
Formula also uses backing plates with the bolts
 
I've owned three brand new Sea Rays and each of them leaked. I've owned one brand new Tiara and it has never leaked. The construction adhesive used by Tiara is very robust. Yes. They also use screws. Yes. The hull is cored on the sides but not the bottom, and it was laid up by hand and not vacuum bagged. The boat is a 2004 32 Open. So far, it is the best boat I've ever owned.
 
I just find it interesting that so many people are ready to jump on the band wagon when it comes to things like hull to deck joints and cored hulls. I know we can dig up old discussions with comments essentially saying that hull to deck joints are crap unless through bolted (paraphrasing), and cored hulls are a risk at best, even if performed correctly. I know I try to use some of the information I get off of sites like BE when I'm researching new boats, for example, and I've always considered the hull to deck joints sub par and of concern if not through bolted. I thought it would be interesting to point out that we have another very well respected boat builder - and yes, obviously I'm referring to Tiara - doing both. As Shel points out, reputation does make a huge difference. The models we're looking at are older so they are not cored, but I would not have reservations about buying a new Tiara with a cored hull should I be lucky enough to be in that market.
 
Regarding the hull to deck seam; I know of more than one way to do it... Rivet is the worst. I own a couple of boats. My Chris Craft has a 1" 1/4 x 6" wood block that is screwed, and attached with 5200, it runs the entire length of the rub rail. My fishing boat is fiberglassed all the way around. You can screw and or bolt, with or without backing plates. Glue/sealer is an option. I would inspect any and all boat mfgr's in these areas, regardless of who built it. I was on a Tiara a couple of years ago, I liked it. IMO
 
Another important variable for these joints is how beefy they are. My last boat would flex in a head sea and leak at the joint. The Tiara has no noticable flex even if you do an occassional hard docking. The rail does not flex or dent. I attribute this to design and thickness of the materials used.
 
My Tiara, being pretty much the smallest they make, is screwed and glued (this is not news, it has been widely known for a long time... ex.: http://www.boatus.com/jackhornor/power/tiara2900.asp). Larger Tiaras I've seen are bolted. That said, even with my boat, there's right and wrong ways of building boats and Tiara knows how to build them right. I live with 0% concern about my deck to hull joint. It might be screwed and glued but it's done right:

1. This hull and top most flex very little, because it all looks and feels sturdy, and I don't have any gelcoat cracks from any screws, or screws backing out of the joint (had that before on previous boat), or anything else that indicates flex.
2. The fit between both is as TIGHT as it could be. Inspecting the hull deck connection, you won't find the gaps that you find in so many other boats (including my previous boat, where there were noticeable gaps in the fit between the hull and deck, caulked). You can "connect" two things any way you want, but if they don't fit right, it isn't gonna work. Tiara will not try to force two things together that don't fit perfectly.
3. The whole joint is backed with marine plywood, where the screws go to. Believe it or not, many boats out there have screwed hull to deck joints, but they are actually trying to screw the fiberglass itself, rather than using wood.
4. There's adhesives and there's adhesives. Looks like Tiara is using the right one. I believe it's Plexus, but I'm not positive.

No boat out there is perfect... But at the end of the day if you're looking for quality, you need to look at HOW they do it as much as to at WHAT they do. I made the leap to Tiara a while ago and the quality difference, when it comes to the bones of the boat, the things that matter, seem significant enough to warrant the extra $.

(As a side note, you can get a lot of info on construction from the Tiara website, go to a model, then to specifications, then click on "specifications guide")... One thing that has caught my eye is that they are going to balsa cored hulls on many of the new models (like the new 3900 and 4300 Open), whereas they used to always be solid glass bottom with balsa cored sides and top on all models up to just a few years ago. I guess if I'm gonna trust anyone on a cored hull it'd be Tiara, but I actually rather like knowing my bottom is solid glass).
 
You must log in or register to reply here.
Back
Top