Best fix for plywood deck checking/delamination

I have a 14ft Jet sailboat with varnished plywood deck that has a little checking and delamination of the top veneer in spots. I want to do a quick fix to stabilize it and paint over it all with enamel. I have some old west epoxy and a couple of new cans of new epoxy filler of the sort you get a home depot for use on your house. Is there a good quick (day or less) fix to make this good for the season or more?

The original cause of the problem looks like wet cover fabric laying on varnish.

 

I dont have any idea what the home depot epoxy is, but I don't think this is a repair a day project. It will be a multi-step process, but I think to could take the boat out on the water between steps if you had a mind to. I see it as a three four day project unless you kick it into gear with some heat. Most likely you could remove the delamed portion, wet out and fill in one session. The filling process could take a couple or three sessions to get it right. (Depends on what you what for the finished project.). Smoothing, primer and paint would take another couple or three sessions.

Or....clean up, wet out, and fill in one morning session. Let cure under heat. Smooth, prime and paint in the afternoon and live with whatever you get until it's time to do it right. One day.

 

Another thought....Depending on the extent of the delamination and whether you've removed any material already, you could carefully lift the lams and inject, poke, brush epoxy underneath to reestablish its integrity and cover with plastic and clamp it with sand bags until it kicks. You could put the sand bags in the sun or heat them in an oven before using them to speed things along. Afterwards, check to see what else needs to be done. I repaired an old set of wooden water skis this way. I just kept feeding the delaminations with epoxy until they would accept no more. The laminations were most likely thicker than what you are dealing with.

 

You are kind of recommending two possibilities when I was looking for a way to make 'good' fast. Let me ease the constraints a bit -one day gluing and filling, set overnight, one day sanding and painting (do I need to repeat?).

Looking at it, I first thought I just had a little checking in spots around the deck. By the time I go to fill I see that the top veneer can move in spots. The ply is not marine grade. I will replace it in two or three years, but it has more than enough structure and its only 3 years old. My experience with 'dig till it's solid' is it's a terrible waste to do it more than once a decade. What I thought I would do is find the lifted/liftable spots, poke a hole and squirt in epoxy (maybe with a little wood flour to fill gaps) and clamp it under some polyethylene to make it flat and level. As long as it doesn't move I feel it's safe to fill and paint.

Does anyone know a better fix? Does anyone know my plan will fail?

 

I think you've got a handle on it. It should hold up for a few seasons or more.

 

Exactly my thought. I must have been writing while you were. This is the kind of experience I was looking for. Water skis are much more demanding than my deck -risking a splintered bum.

 

Thanks, that was what I was looking for.

What do you think about a little fluffy filler? I want the epoxy thin but my biggest fear of failure is that the wood absorbs enough epoxy that it gaps.

 

I would hit it with straight epoxy for 10-15 minutes. Either continuously or every few minutes until it doesn't take any more. I little bit of CS wouldn't hurt, but that really depends on how gappy it is. If it is all laying together pretty well, it may not need it. If it has shrunk and is gappy, you'll definitely want something thicker to fill the voids. First though, give it a thorough soaking with unthickened epoxy that will capillary into the wood and laminations and then apply/inject/insert/smear some thickened mixture to fill the checks or gaps that exist.

 

If the deck is Douglas fir, the delamination and checking might just return in short order - it's the nature of this beast. The same is true of some meranti plywood, not built to the BS-1088 standard.

The Home Depot stuff doesn't sound like a suitable product. You have the real goo, so mix up some of your own filler, with talc/balloons/spheres and a splash of silica to stiffen it up. If the area is fairly flat and horizontal, the mix only needs to be ketchup consistency.

 

It depends a little on what level of "fix" you want, but mostly it depends on what level of ''looks'' that you are happy with.

Structurally you need nothing, as you say you have more than enough. So ''looks'' is what drives this repair.

So, if you remove all the loose bits that are doing nothing and slop a coat of residential latex porch and floor paint on it, you are good to go for two or three years.

If you slop a coat of latex house primer on the deck, and then some exterior spackle sanded down a little, followed by a little more primer on the spackled spots with a finish coat of the porch and floor paint, the looks will improve, comparatively.

Either way you do it, only you and maybe some other person might notice the difference, but in the meantime, you are good to go.

 

If you want a "quick fix" stick to one epoxy system and adjust it to your needs using thixotropic additives. This way you are using the same stuff and can apply the next step before the previous has fully cured.

1. Remove all delamination with an angle grinder + flap disc.

2. Wet out thoroughly using clear epoxy

3. When wet out coat has gelled, ie rubbery. Filled using same epoxy thickened with fillite micro spheres (easy sanding) or collodial sillica (pain to sand).

4. In order for epoxy to sand well it has to be well cured. Can be 2 to 5 days. Sanding of small areas is doable the next day, just don't heat the area too much with all the sanding friction.

5. Fill again if necessary. Sand.

6. Apply paint system.

I would personally tell my clients that this is a 3 day job. Provided that the paint system has a favorable recoat time.