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  #1  
Old 06-08-2011, 09:42 AM
catchemup catchemup is offline
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bay boat in trouble

I purchased a Sea Pro v2300 bay boat new about 9 years ago. The boat has always had problems, cracking gel coat at transom, deck flexing, and screws under rub rail continously falling out loose and bent. Obviously some design flaws not to mention my offshore use in not so friendly seas for a bay boat. Recently I developed a leak in the fuel tank and had to cut the deck to access, I found where the deck meets the stringers no mechanical bond just the deck sitting on top of a hard bondo like substance. This area has crushed the top of the stringers on both sides. With all of this being said, the OX66 sitting on back is in great shape and overall this boat fishes great, rough ride but on anchor incredible and shallow water works perfect. Is there any way to add to the stringers (just two straight up the middle) to stop this flexing, how would I go about adding to the system without a total rebuild?
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Old 06-08-2011, 10:25 AM
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This is typical in many production boats of this style. the adhesive is probably polyester adhesive putty for a boat of that vintage. Newer boats might have used a methacrylate type adhesive.

With either product the bond and support for the deck is typically adequate if done properly.

Steve

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I found where the deck meets the stringers no mechanical bond just the deck sitting on top of a hard bondo like substance.
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Old 06-08-2011, 10:48 AM
catchemup catchemup is offline
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Any thoughts on getting the flex out of the boat, it makes for a terrible ride and some oscillation in a light chop at cruise and above.
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Old 06-09-2011, 02:44 PM
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Perhaps you could sister the stringers, that is add an additional stringer right up against the existing one and glue and glass them together. If you have good access this should not be a difficult project.

Steve
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Old 06-09-2011, 02:56 PM
catchemup catchemup is offline
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I removed the rest of the deck and found a couple of the wings cracked at the stringer joint probably going to sink it or have a bon fire. Nothing is easy without the knowledge of this type of repair.
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Old 06-09-2011, 04:48 PM
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As pointed out, this is fairly common for low end production building practices. They're intended to last the 60 month bank loan, then pretty much deteriorate at a brisk pace. With exceptional care from birth, they hold up for a decade before this happens, but most folks park them in their driveway, where they occasionally fill with water, leaf, acorns and grass clippings, and generally get essentially no routine or preventive maintenance until things start screwing up.

It can be fixed, but it's a pretty big job. Usually it entails removal of the deck cap and/or liner, reinforcement and/or replacement of the stringers/transom, possably some sole support additions, maybe some more hull bottom stiffeners and generally going over it and using the care a custom builder would.

The advantage you have is you can use enough material to make it sound, water tight, strong, etc., plus the labor is free. Manufacture's are constantly trying to control costs so out of sight things, like stringers often get shorted material and labor.

There are several places in the Port St. Lucie area that can do part or all of the work or you can do it yourself. Jobbing it out will be costly, but you can buy materials from these same sources and possably some "side job" help.

Often it's best to isolate each area of concern and attack it with a single purpose. For example, the tank leak and stringer tabbing in the vicinity can be repaired, then then deck patch glued back down. This fixes the leak and shores up the stringers in this area, also offers you some practical experience to help motivate your next foray into boat repair. You may find it's not so hard and you'd like to keep on going, maybe a little at a time. Equally, you might discover this type of work truly sucks hairy donkey pecker and hope you'll never have to get involved with this sort of thing again.

Given good research into the techniques, materials and methods, of which nearly boundless information is available here and elsewhere on line, you can arm yourself sufficiently enough to do a much better job then the factory, right out of the box. Then again, there's always the bonfire thing, which from experience, isn't really very charming as you might think, because it smells to high heaven when boats burn, at least you don't want to roast marsh mellows in it.
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Old 06-10-2011, 07:13 AM
catchemup catchemup is offline
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Thank you for the words of wisdom PAR, I am having some trouble with the how part of this project. SO many opinions and so little fact. The main questions I have are: 1) the stringers are about 12" H x 7" wide what is really required and could I get away with a smaller size that is readily available in the preconstructed foam core, 2) where do I place the wings if installing new, 3) can i regain integrity with just relaminating the existing frames, 4) how much, if the bonfire method was followed, lighter fluid will it take and will the hot dogs pick up any toxins when the kids eat them?
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Old 06-10-2011, 08:03 AM
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The bonfire method will most definetely attract the attention of the local fire department and said attention may include a visit and a fine of some sort.

Once you get fiberglass burning it will burn quite nicely on its own, and I doubt you could get close enough through the thick black smoke to cook a weenie which I would't let my dog eat.

The 7" wide stringer sounds interesting. For a 10 yr old boat this may be a cardboard or foam stringer for which the foam or cardboard were just a form for the structural glass to be laid up on. If this is the case the stringer should be intact as the structural part is all glass, but it sounds like your tabbing might be failing which is not so uncommon for secondary bonds in production boat building.

If the stringers are sound and only the tabbing is failed you cound just grind off the old tabbing and re tab the stringers into place. If done correctly this would not be a quick fix or bandaid but an acceptable and quite adequate repair and because you have the deck off not too difficult.

The method PAR mentioned ("side job" help") is one I have used myself. Around most boatyards there are subs and grunts and many are quite skilled at glass work. Hiring one of these guys and acting as their "helper" can be a very good and cost effective way to make a repair like this while learning the skill.

Got pictures?

Steve

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Originally Posted by catchemup View Post
Thank you for the words of wisdom PAR, I am having some trouble with the how part of this project. SO many opinions and so little fact. The main questions I have are: 1) the stringers are about 12" H x 7" wide what is really required and could I get away with a smaller size that is readily available in the preconstructed foam core, 2) where do I place the wings if installing new, 3) can i regain integrity with just relaminating the existing frames, 4) how much, if the bonfire method was followed, lighter fluid will it take and will the hot dogs pick up any toxins when the kids eat them?
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Old 06-10-2011, 09:05 AM
catchemup catchemup is offline
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My lovely boat pictures
Attached Thumbnails
bay boat in trouble-boat1.jpg  bay boat in trouble-boat2.jpg  bay boat in trouble-boat3.jpg  

bay boat in trouble-boat4.jpg  bay boat in trouble-boat5.jpg  
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Old 06-10-2011, 01:30 PM
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I think what I see is only tabbing failure.

Are the stringers foam filled?

Steve
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Old 06-10-2011, 01:47 PM
catchemup catchemup is offline
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Yess foam filled but some areas of the stringers looked crushed
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Old 06-10-2011, 02:23 PM
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Maybe others might have different ideas.

In order to do this fix right you will need to grind any surface you plan to glass to in order to get a good secondary bond. Where the stringer looks crushed you will want to consider laying up some extra layers of glass to bring the surface level with the rest of the stringer while providing extra strength.

Then you will have to re tab all the stringers and transverse framing. I would do the whole thing. I would suggest that in order not to disturb placement that you not grind away all the tab bonds but leave some just so everything doesn't move and then come back after and do those spots. The boat needs to be blocked up real carefully for this so the hull doesn't move around when you start grinding tabs away.

Another option would be to use a methacrylate adhesive like Plexus which has basically replaced tabbing for these type joints. Instead of a secondary mechanical bond methacrylate creates a chemical bond that is strong and durable. You would still need to grind away existing tabbing but these adhesives come out of a caulking like gun with a mixing nozzle, much easier that tabbing with glass.

Just one source:

http://www.jamestowndistributors.com...dwords&keyword

Steve
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Old 06-10-2011, 07:08 PM
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The first decision you need to make is foam or wood. The second decision you need to make is will the actual stringer carry the load or will the laminate.

If you choose foam, the second decision is already determined, the laminate has to carry the load, which means much more 'glass work then a load bearing wooden element.

If you choose wooden load bearers, then they need to be waterproofed and tabbed to the hull shell with sufficient laminate to insure they can't come loose. This requires less goo and 'glass work, but you have to cut and fit wood and also waterproof it.

Properly encapsulated in epoxy (waterproofed) the wood will last for generations. If at some later point you drill a hole or drive screw into it, this will need to be sealed with epoxy or you've created an entry point for moisture, which you already know can cause other issues.

As has been pointed out, all areas where the replacement pieces, be this foam, wood or 'glass need to be ground clean and down to good laminate. Use a ridiculously coarse sanding disk (16 - 36 grit) for this work, so you have plenty of tooth for the secondary bond to grab a hold of.

Make sure the tabbing is at least as thick as what was once there and use epoxy, preferably with a biax tape (45/45 bias) or fabric, instead of cloth, it's a lot stronger for the same weight. If you follow these guidelines, the same size tabbing and laminate that was once polyester and mat will be several times stronger in epoxy and biax. This will eliminate any movement and undo flexing.

I don't trust Plexus alone to hold structural elements, but on sole supports and other not very heavily load pieces, then Plexus alone (no tabbing) works fine, considering the cost. Nothing personal Steve and I have to qualify this with I haven't cut up too much (repairs) with Plexus joints in it to make this assumption. I'm just concluding that the jury hasn't been out long enough for me to have full faith in it yet. At least in my experiences with it.
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Old 06-10-2011, 10:44 PM
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"Nothing personal Steve and I have to qualify this with I haven't cut up too much (repairs) with Plexus joints in it to make this assumption. I'm just concluding that the jury hasn't been out long enough for me to have full faith in it yet. At least in my experiences with it."

A very conservative position and one I don't have any problems with. I threw that out as an option, and note not the first suggestion. Our friend catchemup here has some apprehension over skill level and I thought Plexus would be a good option for someone with limited glass skills. Stringer tabbing is a bad place for a learning curve to start.

A large segment of the production boat industry has a lot of faith in Plexus. I've seen destructive testing that is pretty impressive, you've probably seen it at IBEX yourself. I agree it hasn't been in the field long enough to determine what long term strength will be in the real world, but it is pretty impressive stuff and many high end builders are adhering stringers and grids with it.

In our little business we use it a lot on small parts, so far so good.

Your suggestions to use epoxy and biax tape is tried and true and will provide better than new strength.

Steve
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Old 06-11-2011, 03:46 AM
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When I was younger, I jumped all over the latest and greatest new products and techniques, but got burned more then once, when years later I'd seen or had to redo something. Now, I use a more pragmatic approach, so if a product has promise, I'll do some tests, watch the industry and wait until the jury comes in. After the spanking I took on penetrating epoxy in the 90's, I'll continue to use this methodology, even if it's a tad conservative.
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