Experience with cracks on deck

[87compac23]

Hi all,
Wondering any of you have experience this.  On the deck where the cabin meets the deck on the two front corners, I have cracks.  I had then repaired awhile ago but alas the had returned. I had caulked the heck out them to keep the moisture out when they returned and am fixing to have them repaired again by my marina resident fiberglass guy.  I'm told that its a natural result of "flexing" of the hull. Another is it's caused when the boat is taken out of the mold etc.  I had one person tell me I had to put a brace under the spot on the cabin to reinforce the area (I think he had a car payment that needed to be made). Boat's an 87 so she's been around the bay a few times. Interested what others have encountered.
Ralph

[hockeyfool]

  I have them also, been working to resolve as i did seemingly fix a couple located at the stanchions, near bow pulpit.
So - according to a marine service technician whom posted fiberglass/gelcoat repair on Youtube, the area needs to be sanded or grinded down several inches outward, or making a "V" groove
then using finely chopped fiberglass with polyester resin to fill over crack. Then sand down, use more resin as fairing compound to fill in and level out, then sand again, then apply
gelcoat.
He said it was caused in production issue of trying to apply enough fiberglass cloth at corners -- which seems to be insufficient in many boats. 

[NateD]

It's hard to give definitive advice without seeing the boat, so take it for what its worth. Assuming the cracks are just in the gelcoat, then it is most likely flexing that is causing it. If you don't fix the flex, any repair made to the gelcoat will only be temporary and the cracks will come back. Grinding out the cracks and adding mat/resin back to the original thickness won't fix it long-term. The CP27's also developed cracks in that spot, take a look at this thread: http://cpyoa.geekworkshosting.com/forum/index.php?topic=6196.0

A simple cosmetic fix doesn't work. The deck is too flexible and the cabin isn't.

and

I have an '86 and have been fighting this problem off and on for about 15 years.  So far I have (a) 'Roto-ed" and re-gelcoated the cracks, they came back, (b) when I reworked the interior added two layers of mat glass on the inside around the corners, re gelcoated again... they came back, (c) when I painted the boat, (Awlgrip) best decision I ever wrestled over,  I opened the cracks again and filled with epoxy before priming and paint.... guess what.... they are back.  Smaller but there they are.  I can see NO structural damage, the cracks have never been more than surface deep and the latest are not where I epoxied before painting.

You're going to have to build up some glass on the backside of it, and it looks like you'll need more than 2 layers (he doesn't say what weight mat though, and this was a 27, not a 23, so maybe only 2 layers of heavy mat?). Even then, they might come back. The good news is they are probably only cosmetic (again, can't say for sure without seeing the boat), so you can just ignore them and keep sailing.

[MacGyver]

Use Epoxy resins and glass.

Corners are typically not spreading the load evenly enough, so it generates it to one spot, the weak link.
By cutting open to the bottom layer of the sandwich, you can reinforce by building out. This for me is a bigger job than that of a I type, you read kind of thing to repair it correctly....... But I can tell you the key is more glass in that location spreading it outa little wider.

oh, and Epoxy Resin........

Mac

[Jon898]

Gelcoat cracks in older boats are very common.  They are usually due to a combination of a high-stress area in the fiberglass and years of UV exposure.  Your gelcoat is over a quarter century old and has probably been polished thinner over time as well.  The exception is when the cracking shows up in a young boat, when it's usually due to excessive gelcoat thickness at a stressed area or insufficient strength in the molding (bad layup or missing backing plates).  If they are located away from an obvious structural source of stress (mooring cleat attachment, mast tabernacle, jibsheet leads, etc.) so-called "spider cracks" are probably just a cosmetic issue and can likely be left alone, particularly as CP's don't use balsa or plywood coring as far as I know.  This may no longer be an option for you if you've caulked them to death already.

The corners of the cabin, because of their form rigidity, will present a significant point load to the deck, and I would not be surprised to see spider cracks radiating from the corners over time...I had that on a Newport 28 I owned many years ago and two different surveyors dismissed it as "cosmetic/of no structural concern".  That would not be the case if the cracks are large (wide) or close to a highly loaded piece of deck gear, in which case a repair would be mandated.

I suspect that a "fix" will only be temporary, and you will see the cracks return short of launching on a major surgery/reinforcement exercise.

I'd be interested in Mac's take on this as he's in that business

[brackish]

I may have the newest (2005)of the 23's of those who post here and I have them and they were there when I bought the boat from the PO.  I've owned three other boats and sailed on many, many others and have not ever seen a boat that is free of spider cracks in the gelcoat at various high stress points.  I think trying to fix them is pointless unless you are prepping for a paint job.  I fixed all of the above deck cracks on my Columbia 8.7 with epoxy then coated the whole thing with catalyzed polyurethane.  That seemed to work but I only did that to prep for the paint.  

My view, learn to live with them.  If you live in an area that has freezing temps and your boat is left out in the weather, rub some wax in the crack areas as part of your winterizing to keep water out and avoid the small possibility of frost heave damage.

[87compac23]

Thanks for all the replies. I agree with all the analyses.  The good news is that they never have gotten worse and have remained stable. May be overkill but I do shrink wrap every year to avoid freezing damage. A lesson learned after my O'day 22 had a portion of my deck blown apart around a stanchion when water water infiltrated, froze and you know the rest of the story.  Sort of figured others would have the same experience although a little disappointing to hear they don't stay gone.  Another thing I was going to try and this may sound crazy.  I have an in-ground pool with fiberglass steps that were unbelievably cracked, crazed and literally falling apart. My pool company has a guy who repairs steps. While  the liner was being replaced this guy had this veneer material the he bonded to the steps, filled and fared them to match the curves and then epoxied over with a non skid finish. Truly amazing repair and warranted for 2 years. Tried to get him to look at the boat but he's too busy doing steps or just wasn't into it. Seeing what he did made me think they would never come back. Heck,  I'll get them fixed cause that's just me and learn to live with periodically having them come back....unless I can con the pool step guy lol.

[jb]

I've used this product to seal potential areas of concern.   http://www.captaintolley.com/   





j

[Bob23]

It's not overkill to cover the boat if you live in a northern climate. I cover my 23 with a Fisher Canvas cover. Keeps the sun, snow, ice and salt off the boat. As with all women, our sailboats like to look younger than they really are.
I have some of these pesky little cracks and realizing that perfection is unattainable in this world, choose to keep the boat as nice as possible without becoming a lunatic and enjoy her with all her minor flaws. Maintenance is one thing. Obsession quite another.
Bob23