Repair of cracks in deck of 1983 O'day 25

[ddooher]

I am developing thin spider cracks on the deck, that I have seen in numerous older O'Days. The crack is in the middle of the deck between the cabin way and the mast. An area around the crack is approximately 1 ft square.

What are my options. Is there a clear expoxy I can put on the cracks. I'm assuming that is not a good idea as the moisture will be trapped and the area will still deteriorate. Does the spongy area have to come up and the fiberglass replaced. Any ballpark estimates on this type of repair. Thanks.

 

[jfschena]

West system has a free download called "fiberglass boat repair and maintenance". You should find how to do most jobs there. Sounds like a recore if its soft.

As far as the cost: a quarter sheet of marine ply; half gallon of resin and hardner; some filler, cloth and materials. . . . . There are also a lot of restoration projects with pictures on this forum if do a search you might find a project close to yours.

 

[ddooher]

Thanks for the advice.

 

[GeorgeC]

I am developing thin spider cracks on the deck, that I have seen in numerous older O'Days. The crack is in the middle of the deck between the cabin way and the mast. An area around the crack is approximately 1 ft square.

What are my options. Is there a clear expoxy I can put on the cracks. I'm assuming that is not a good idea as the moisture will be trapped and the area will still deteriorate. Does the spongy area have to come up and the fiberglass replaced. Any ballpark estimates on this type of repair. Thanks.

The spider cracks may be outlining areas of the deck where you have a space between the gelcoat and the fiberglass under the gelcoat. You can find if there is a unsupported section by tapping with the handle of a screwdriver and move from ouside the crack and across the area inside the crack. If there is a void (unsupported gelcoat) you will definitly hear a differnce in sound as you tap across the deck and tap on unsupported gelcoat. I've had them on my 1983 O'Day 30 and they can be repaired. I drill two 1/8" diameter holes at each end of the area that sounds like it is hollow under the gelcoat. Only drill down through the outter layer of the gelcoat and not through the fiberglass below. I blow presurized air into one of the holes with a syringe to make sure the area is vented out to the other hole you drilled. This is important as when you inject the epoxy you will need a vent hole for it to allow the epoxy to flow under the gelcoat. If water comes out of the second hole I would let it dry out for a few days before proceeding. If there is a void, the second hole will allow air or epoxy to vent out of the second hole. Make sure you only put enough air pressure to move the air out or you may cause the gelcoat to crack and release the air. I would then mix up some of the West System epoxy and inject it into the hole with a West System syringe until it flows out the second hole. Monitor it until it gets hard and keep cleaning the area around the holes as the epoxy will come out as it heats and cures. If the epoxy does not fill the drill holes when cured, I fill them with Marine Tex. I then mix up some colored gelcoat and color in the two holes and dab some into the spider holes in the gelcoat. This works if there is a void under the gelcoat where water has not contaiminated the balsa core material.

 

[ChattOday]

Let me add: I just completlely refurbished the entire deck of a 1977 Oday 22, so all of the info and issues are fresh in my mind.

In my opinion, the problem is a weakened core due to water infiltration. I can guess, probably without even looking, that some of the holes into the deck (lights, railings, wood toe rails, rigging, etc) have lost their waterproof sealant and as a result water has worked its way into the middle of the fiberglass and into the wood core. Over time, it has rotten and weakened the core.

The crack (of which I had MANY) are the outward sign of an internal problem. The cracking is the product of the outer deck having to much flex. In essence, because the structural core is weakened, the deck is able to flex under weight too much and cracking has resulted.

This is exactly what happened to me. If you simply repair to outer, it will come back quite quickly. The flexing will still occur. That doesn't mean you can't do it, I just wanted to let you know that from just doing this (literally Feb - June of this year) and give you my .02 cents.

The long term, permanent solution is.. well.... time intensive, but the end result will be a new deck that will out last you. You need to see how much water infiltration has occurred and fix it. That happens in 3 stages:

1. Diagnoses. In areas with severe cracking, you need to drill into the wood (from the cabin up) and get to the core. If the core wood comes out wet then you know it is rotting and weakened.

2. Fixing the problem: You need to repair the core. Buy a book, there are multiple ways to do it depending on severity and labor load.

3. Resealing ALL HOLES. To prevent it from occurring further, you remove all through deck holes. Everything with a screw, nail, hatch (etc.) and seal it. I used 3m 5200 and sealed every hole up.


THEN you can repaint or Gel Coat and not worry about crack coming back. Attached are some and after photos. I repainted her back in June and have been using her every weekend. Not a single crack has returned. Obviously, time will tell, but the deck is stronger than ever. I can jump into the water from the bow deck all day she it doesn't flex at all. The boat moves, as it should, not the deck.