Crack in cockpit floor

[Milton.Audas]

G'day. Has anyone encountered this cracking problem in the cockpit floor of the early model (1980) C-22's ? I have skived it out, filled and reinforced it a couple of times and it persistently reappears. My thoughts are next to reinforce on the under side with metal bars (angle iron or similar for strength) overlaid with fibreglass. But any ideas on root cause and/alternate repairs ? Could it be hull flexing ? Interesting that the crack aligns with the for'ard lines of the cockpit lockers (structural or design issue ?). Surely the cockpit floor would not have been laid with two pieces of board that have over time flexed and separated beneath the fibreglass ?? No head-banging, zombie stomping parties on board that I recall. No-one jumping off the cabin top into the cockpit. Kept in water on a marina slip all summer, and stored indoors on trailer for the non-sailing part of the year. Appreciate your thoughts...

 

[Leeward Rail]

I can't remember who it was, but there was a thread in the last year or so, where someone rebuilt their cockpit sole.
Maybe the photos in that thread will give some clues on how they cored and reinforced that part of the boat.
Who knows.. maybe they did use 2 pieces of plywood.
Any softness or hollow sounding areas on either side of that crack ?

 

[pclarksurf]

Might have been me: page 4 and 5

https://forums.sailboatowners.com/index.php?threads/today-it-gets-real.178757/page-5

Big kicker is that the substrate is natively crap— included some pics, but throughout the c22 you will find two thin plys bonded with what I assume was epoxy. Lots and Lots of voids — to the extent that I could never grind back to a solid surface. Rather than fight the crack and the voids I replaced with solid ply/ encased in penetrating epoxy on all sides. Get underneath and you’ll note the underside of the original is raw wood— and likely a nightmarish mold factory

 

[Will Gilmore]

Do you have pictures of your boat sitting on her trailer? Rollers or bunks? That is a stress crack from hull flexing. Odd that it should occur in the cockpit sole, though. Unless there is a frame or support member pushing up on the sole when on the trailer. I would think hull flex would show up more on the deck level as that should have greater movement when flexed. The cockpit sole should be floating.

- Will (Dragonfly)

 

[Jacktar]

I would certainly look at the underside to see what is going on under there, a good fiberglass patch should stay patched unless something is soft or sinking under it. Sounds like a candidate for a nooks and cranny pix with smartphone or go pro. As example here is back side of liner where the dinette table attaches on my boat.

 

[pclarksurf]

I'm guessing that crack is a bad repair on top of a void or some compromised ply -- @Milton.Audas first pic shows the big obvious, but there's a ancillary crack north of that in his pic as well. As a reminder the cockpit is an integral part of the deck -- completely supported by the lazaratte and surrounding structure-- flexing the boat on that axis would be a feat to say the least. My money is on a bad repair or failing substrate:

 

[Gene Neill]

I agree with the last two posts.

 

[Jacktar]

Me too probably due to bad repair, cockpit bottom is supported only by its sides and does not bear on anything below. Still be nice to see what it looks like underneath, post it when you do.

 

[whatcaneyedo]

This was my solution to a similar problem. I flooded the cockpit floor with fibreglass resin, cut a sheet of 5/8" plywood to sit on top, fibreglassed the top then sanded it smooth and painted the area.

 

[Jackdaw]

Do you have pictures of your boat sitting on her trailer? Rollers or bunks? That is a stress crack from hull flexing. Odd that it should occur in the cockpit sole, though.

Will, I really really really doubt that.

 

[Will Gilmore]

Will, I really really really doubt that.

It sounds like you are right.
It was odd to be in the cockpit sole.

- Will (Dragonfly)

 

[Milton.Audas]

Thanks W.H.. Nice restoration job ! Your solution is what I have I mind. Did you have any thoughts on root cause ?

 

[Jackdaw]

It sounds like you are right.
It was odd to be in the cockpit sole.

Not really at all. That is a LARGE span of flat decking, devoid of any structure that would add strength. Add 40 years of use, questionable design for intended use, and you are one 250lb dude stepping from the seat to the middle of the floor away from a crack.

Many boats will have a ridge down the middle of the cockpit floor to add a 3-dimensional element that greatly adds to strength, along with its other purpose, a dandy foot-brace when heeling. You can put a ridge on the inside, but then you loose the foot-brace!

 

[Milton.Audas]

Thanks guys. Really appreciate the advice. I have been inside both port and starboard spaces and no signs of hull distress. I agree that hull flexing is possibly not the root cause. Likely some flexing or separation of the ply beneath. I like WH's approach to covering teh sole. Had also considered applying Seadek which would look nice. I will get under the sole next weekend, pre-armed with bracing and fibreglass. Will post pics of what I find, and actions taken. WH (nice finish !!) and Jacktar's pics are great, as well as the link provided by PClark.

Attached pic of boat on trailer (excuse apparent mess as we had just pulled from the slip and were preparing for winter storage). I can get a more detailed pic of the hull-trailer bunk area next weekend.

 

[Milton.Audas]

Agree more structural support needed. Will apply 3-D bars (possibly high grade plastic 1.5" angle stock) from below, epoxied in and serious application of fibreglass matting. FYI, the 'Purser' would get very agitated should I approach even 200 lbs. Probably be keel-hauled and rum rations withdrawn. :-(

 

[Jackdaw]

Agree more structural support needed. Will apply 3-D bars (possibly high grade plastic 1.5" angle stock) from below, epoxied in and serious application of fibreglass matting. FYI, the 'Purser' would get very agitated should I approach even 200 lbs. Probably be keel-hauled and rum rations withdrawn. :-(

Solid plan. Re the 2+ bills, I'm with you there. That could be from a PO and/or his friends!

 

[kloudie1]

These are pretty neat .. Pre made and easy to install..
https://www.jamestowndistributors.c...milyName=Prisma+Composite+Preforms+Hull+Beams

 

[whatcaneyedo]

Thanks W.H.. Nice restoration job ! Your solution is what I have I mind. Did you have any thoughts on root cause ?

Thanks. I wonder if maybe a previous owner gouged it with the keel of an outboard motor. There were a lot of damaged/neglected things about my boat that didn't make much sense.

 

[Gene Neill]

My cockpit had a crack in it when we first bought the boat. It had had more than one unsuccessful repair.

Deeper surgery revealed it was caused by a large void in the layup. On well-placed stomp could have cracked it on the showroom floor. I dug out all the wood, replaced it with new (saving a little at the forward end which had no rot) re-skinned it and kiwi gripped it. I don't feel like plywood this size and thickness needs reinforcement, but it dang sure can't hurt. And it doesn't cost much, or add much weight, or take up any room. So have at it, I say.

 

[pclarksurf]

Deeper surgery revealed it was caused by a large void in the layup.

Every time, all day every day-- short of significant rot/catastrophic failure of the subtrate, the voids in our layups are seriously problematic. Not solid ply -- but two smaller pieces sandwiched together with 70's era epoxy like "stuff". As Gene has done-- Replace and be fruitful.....