Flexing of cockpit deck

C

C spot swim

New member
Hello everyone, first time posters here.

We just received our boat and are having a great time with it in Alaskan waters.

We have a call out to the engineer who surveyed our 2005 22' Cruiser before purchasing but in the meantime we'd like to draw on the experience of this great forum.

While inspecting the boat after arrival from out of state, we pulled up the Dri-Dek and noticed fairly moderate flexing in the port cockpit. It's a small section; a 1.5sf section that probably flexes 1/4 inch in an even, inward manner throughout that area. It is not noticeable with the Dri-Dek on top due to weight distribution nor is the flexing so extreme as to be discerned through pictures.

We cannot discern any obvious patching, previous deck work or hull problems in that particular area.

Anyway C-Brats, before we hear back from the surveyor, we would like to ask if this flexing is something not uncommon in these boats and has anyone experienced this?

We've been silently reading for months and will appreciate your time and suggestions.

Mike & Rachel
 
Mike-

I may be wrong, but I don't ever remember any mention of flexing of the hull in this area or any area of the hull, unless seriously compromised by water intrusion, such as in a Classic 22 with a saturated plywood core.

The hull in your boat is balsa cored at that point, and probably 1-1/2" or more in thickness. My '87 doesn't give at all, and I wouldn't expect yours to do so, either.

Does the spot of flexing match any bunk or roller support on the trailer that may have been overloaded ?

Let's see what others have to say!

Joe. :teeth :thup
 
Mike,

Are there any fiberglass penetrations in the neighborhood of the flexing? You mentioned not seeing obvious repairs, but water might be getting in around a very nice looking fastener or other fitting.

I've got a strong feeling, based on your description, that the balsa is compromised to the point of rot. A properly adhered fiberglass core sandwich is really quite stout. I've been surprised to learn how thin the core can be and still maintain a high degree of rigidity. On my old boat, the core is just 3/4-inch plywood. Much of the plywood core became saturated but it didn't rot and remained solid after drying out. My balsa-cored transom didn't fare so well; it was almost totally rotten.

Best of luck with the survey, and hope I'm wrong about your core.

T
 
Nunya":2voxiuih said:
It's the deck flexing not the hull right??
Click to expand...

Unlike your C-25, the C-22 cockpit deck is the inner hull on the 2005 and earlier. Outer hull, core, inner hull sandwich. C-22 owners happily walk below the waterline. I would be very concerned had I found flexing in the actual hull structure of my 2005 C-Dory. That was the year factory quality issues began rearing its ugly head. I'm not saying all boats were affected but the percentage of boats delivered with problems allegedly begin increasing later in 2005 and apparently didn't slow down until the factory was taken over by the present owners.

Don
 
Joe,

Hi, good thought about the trailer. My trailer has running slats, not rollers so therefore it is the one area on the bottom that I cannot see while it is on the trailer. I don’t want to dive in our 48 deg. water. :!: Perhaps the surveyor that I called today will have it hauled out to fully inspect it, perhaps drill a hole in it, etc., I don’t know.

Mike

Tom,
Hi, no fittings/screws in that area that I can see. Like I told Joe (Sea Wolf), I’m now concerned that there is a gouge under the trailer slat perhaps that I can’t see, who knows? We have friends that had to replace a lot of fiberglass in their first boat due to water damage and it was doable, but quite the project. Not exactly what I had in mind for my first summer with this boat. :?

Thanks for the “good luck” on the survey, I too have a sinking feeling but until it’s figured out I’m just going to take the dogs for walk.

Mike

Nunya,

Hi, it is the deck that flexes, correct. I am going to go back to the boat today with my wife and see if, while standing on it, the outer hull flexes too, etc.

Mike

Don, I appreciate the info on the 2005 models possibly having quality control issues.

Mike

All: I will keep the forum posted on the findings of the new inspection by the surveyor. Don’t know when that will be, he is very busy. Thanks for everything and wish us luck! :beer
 
I have an 05 Cruiser, no flexing spots on the floor that I can find. It does have a through hull for the raw water washdown and there are metal brackets ("L") the hold the bulkhead in front of the fuel tank. All still tight, and so I have not moved them.

Good luck, and please let us know what you learn.

Thanks,

Harvey
SleepyC :moon
 
"Flexing" means that it is moving. Is it moving or has it just bulged in, creating a lump. If that's the case, I'd be concerned that the core had gotten wet and has swollen up.

Charlie
 
Didn't think I would be posting back already. Got a few findings/opinions today from a reputable boat repair guy locally who is very familiar with C-Dorys and was able to look at the flexing.

He said it could be a few things just off the cuff (without drilling to make sure):

1. Screws that hold the plastic brackets for the fuel tanks could be letting water in. (Harvey: keep an eye on them!)
2. There is a bilge modification inside the cabin door (hinged step) that was cored out (don't think it was a factory installation) that could have been done improperly.
3. He's not sure if the resin that was originally injected and brought through the wood core gaps was properly suctioned through every gap creating a bonding issue.
4. A combination of things: bonding issue but dry core, bonding issue plus water invasion, etc.

(Charlie: it flexes in with pressure and when pressure is released, the deck returns to its proper looking level. It is spongy feeling.)

Fortunately, I say fortunately even though I thought I was purchasing an excellent find, :? the repair guy doesn't feel the boat is unsafe and the repair will be likely less than a $1,000 even in a worse case scenario with a fair amount of rot.

I took a marker and outlined the questionable area and will keep an eye on it. If the flexing spreads beyond the outline I will get it repaired sooner. As it is, the repair shop said we can wait until winter to get in there though I will probably get the boat in the shop by September.

If I find anything more I will be happy to share. Thanks for the feedback as it really was the boost I needed to call someone today rather than wait a few days and continue stressing out about it. I feel a bit better knowing that it doesn't sound like a $10,000 fix!

Our trip through Chatham to Icy Strait and into Port Frederick next week remains on the schedule. :thup

Mike
 
Mike,

You can pull the screws that hold the cleats for the fuel tank yourself. I was concerned about mine, so when the cleats started pulling due to the fuel tanks, I had the starboard retainers replaced, and the cleats re-bedded. The holes for the screws had been sealed with something like 3M 4200, and there was no water intrusion. I suspect if that was the area that was allowing water in, you would know it when you pulled the screws and cleats.

Steve
 
hello michael,
i've been following this tread and had immediately thought that water got to the hull inner core. when you mentioned to charlie about it feeling spongy, that kind of cinched it. there's been many post regarding a compromised core as well as the repair process. so far i haven't said anything new, just wanted to post letting you know, we feel your pain. seems like just around every corner there lurks a possible, day ruining disaster. while this doesn't qualify as a disaster, we did get into boating to reduce stress and enjoy life, not dealing with issues like this. if possible post pictures when they make the repairs. do you intend to use the boat up to the point of repair?
good luck
pat
 
Mike,

Here's a reference to boat repair and installation of fasteners and other fittings from West System's Web site. http://www.westsystem.com/ss/use-guides/ Scroll down the page to "Advanced Techniques" and download the PDF file for the second one: Fiberglass Boat Repair & Maintenance. Lots of good info whether you do the job yourself or just want to talk knowledgeably with your contractor. There are other good references available online or books; I just bought Fibreglass Boats, a book written in 1963 about how to maintain, outfit, and repair glass reinforced plastic (GRP) boats. I love it because it contains no market-speak hype; the author's direct and to the point with a rare bit of understated humor. All the basic issues we need to deal with on a fiberglass boat today were there back in those days. I got the old version but there's a 2008 edition available for under $40.

If you have one, or access to, a pinless moisture meter it can be very telling about where and to what extent your boat has water intrusion. Forget the specific value readings, just use it to check the variance across your cockpit sole; while you're at it I'd check the transom as well. I used a pencil to trace where the values were 10, 20, and 30% ending up with a contour map of my sole's moisture issues. 'Twas very telling and educational.

All the best,

T
 
Hi,
Maybe you could hope that you had the optional floor boards installed and that there is nothing wrong with the core on your boat at all and it's the floor boards flexing. Just a thought.
D.D.
 
Will-C":vmmo1tlj said:
Hi,
Maybe you could hope that you had the optional floor boards installed and that there is nothing wrong with the core on your boat at all and it's the floor boards flexing. Just a thought.
D.D.
Click to expand...

DD- Good poiint!

If you read, and re-read all the posts above, I don't think it's been firmly established whether it is the floor board inserts ("deck") or the actual outer hull that is flexing.

Some posters seem to assume one, others the opposite. It's not entirely clear the way the words are used.

Mike- Do you know if you have the flat floor board inserts installed over your hull, or if your boat is without them, and you stand on the inside of the hull itself?

If you have the inserts, have you tried picking them up to see if they are flexing, and the outer hull underneath is solid?

Some photos would have eliminated the ambiguity from the start!

Joe. :teeth :thup
 
Thanks Joe I'm a sucker for the kind words. I seem to remember Starcraft Tom having a 2005 22' cruiser that had floorboard issues that he pulled up and redid because of the lack of support under the installed floorboards. I'm thinking Tom posted pictures of the fix in the thread. I really don't know as I have a 23' Venture which are listed as just other on the C-Brat map. I'm drifting off topic here.
D.D.
 
Hi Steve,
I do intend to pull those screws and check out the fuel tank cleat areas. I have a garage for the boat so there is no water getting in it currently. But yes, great idea since it won’t be torn into for a month or so, no need to continue to possibly have more water enter until then...

Mike

Pat,
Hi, I appreciate the words-totally spot on about types of stress. Yes, I will post pictures when I get them. I do plan to use the boat until it’s fixed as the fiberglass guy was confident that there isn’t a safety issue here. But I do want to find the source of water entry (if that even is the issue) since I will be using it for a while.

Mike

Tom
Wow, thanks for that site. My repair guy pretty much echoed everything you sent so that was reassuring to me. I am one of those guys who could do it myself but it would take twice as long and I would be going back and forth to the store buying tools I don’t currently have…Considering the fix under a thousand, I’m just going to bite it on this one and have it professionally repaired.

I didn’t have the repair guy use the moisture meter as we didn’t have a lot of time yesterday but I was intrigued by it. My wife is a veterinarian and we have jokingly discussed using our portable ultrasound and x-ray on the deck/hull but whether or not it would be diagnostically useful is the question. Radiographs probably won’t be helpful but ultrasound could be interesting especially if there’s a lot of water intrusion.

I will look into getting that book, sounded good.

Thanks,

Mike

D.D. and Joe,
Sorry about not having photos, that would have eliminated confusion. I don’t have floor boards, just Dri-Dek. I am calling the bare cockpit floor the “deck”. It is the fiberglass itself that is flexing with pressure not any sort of false decking. Joe, I don't have flat floor board inserts. I will work on getting some photos taken and posted.

Mike
 
DD & Joe,

Scratch that. I don't really know if I have permanently installed floorboards or not. The cockpit floor does not seem elevated but now I will have to go back and look and post some pictures.

Thanks for the suggestion. :thup

Mike
 
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