need help sealing wood floor

[AstoriaDave]

Dave and Bob, thank you for your advice. Don't let the consent distractions of aging , wondering minds throw you off. I do appreciate the help :wink:

you are welcome. Those guys are just leavening the mix. My mind wanders some, also.

BTW, first deck panel you glass, be good to have someone on board who has done it before. Most folks make their epoxy batches too big and let them sit in the mixing pot, leading to an exotherm in the resin and it goes off. You have probably seen this with polyester resin from working with it before. I usually stick with 4 oz plus 2 oz to make 6 oz batches maximum, and pour it all out on the glass covered panel, then squeegee it around until the glass is wetted out and the resin coat is uniform. Others like to use rollers, which is good for the resin when it is thin, before it starts to harden. The S3 epoxy book has a lot of good tips in it.

 

[thataway]

We all have slightly different techniques and they all will work. I pour and squeegee the coat on the plywood, so it is on good and thick. I like to leave enough epoxy on the surface, that when I lay the cloth down, some resin will come in to the cloth from beneath. I like a roller for the coats over the cloth, but have also used the plastic blade squeegee. Just be cautions to be sure there are no bubbles. If you have two people to put the glass down; one on each side, will made sure it lays down flat, with no bubbles. If you cannot get wide enough cloth you may want to go with a very slight overlap, or butt the two pieces of glass exactly together.

Same with how you finish off the surface--but paint with or with out nonskid. The epoxy does have to be covered with paint to prevent UV deterioration.

Tom, throw up some photos when the floor is complete!

 

[starcrafttom]

I will try to take photos of the project along the way. I think I will only do one piece of the floor the first time. I will also glass both sides. Most of the water will be sitting under the floor.

To be clear these are removable floors that will just be laying in place on a alum open sled. Oh a sled is a flat bottom jon boat with a out board and jet pump. I will take pictures of the boat too. It will make it all clearer. Most of the water is rain or splashed in water and it will me on the hull. The floor is to keep me out of the water and to level the floor for moving around.

 

[AstoriaDave]

We all have slightly different techniques and they all will work. I pour and squeegee the coat on the plywood, so it is on good and thick. I like to leave enough epoxy on the surface, that when I lay the cloth down, some resin will come in to the cloth from beneath. I like a roller for the coats over the cloth, but have also used the plastic blade squeegee. [Snip]

Tom, throw up some photos when the floor is complete!

Yowsa on the photos. With glass on both sides, those boards will last forever. BTW, probably do not need to paint the underside. Not much UV exposure down there.

Agree with Dr. Bob there are a lot of ways to skin this cat.

I have glassed over wood precoated with resin, partially cured, most of the time, and maybe 10% of the time over bare wood. In all cases, the wet out resin went down after the glass was laid out, even times when I had to overlap. For large areas such as Tom will be working, I would be concerned about laying out a big swatch of glass over wet resin. However, it worked for Dr. Bob. I bet he has some tricks and tips on using that method. Maybe working from a roll, and gently pulling the glass out to the sides as you unload the roll?

For me, seems like the glass is still shifting a little bit when I work the squeegee hard, pulling excess resin off the glass, last pass, dumping the excess into an old yogurt container or a throwaway pie plate.

 

[Sunbeam]

I will also glass both sides. Most of the water will be sitting under the floor.

Something that came to mind when you mentioned glassing both sides. That is that you don't want to make a situation where you now have a sealed (but not really sealed) sandwich that can trap water and rot your "core." I'm thinking that with these boards you are not counting on the fiberglass for structural strength (as you would in a cored deck), but rather for keeping checking down and providing abrasion resistance on the side you walk on. In that case, if it were me, I would probably glass the tops with something like 6 oz. cloth and simply coat the rest with neat resin (then paint). Perhaps add non-skid to the top. Maybe heavier cloth depending on how you are going to use them (but still only on the top).

Seems like in this case glass on both sides will just add weight and the potential for "trapped" water. But, like others say, many ways to approach it.

One other note is that fir plywood is notorious for checking, but others will not be as bad. So I'd try to stay away from fir, even if you don't go for marine plywood (marine ply won't be fir). I once bought a ply/epoxy boat that had been built with fir and only epoxy coated on the panel sections (no glass) by the original builder. Check city! I had to sand the whole thing down and lay 6 oz cloth over it, then re-paint. What a pain :cry

 

[thataway]

There are some good reasons to glass on both sides. The standard in boat building is often to glass on both sides of plywood. For example many boats have plywood (often not marine) in their decks, floorboards, bulkheads etc.

In Toms case if the floor boards are going be in a situation where there is water on the bottom of the floor boards (common situation in floor boards), then glassing the bottom may be the best course.

The problem with C Dory core (and remember that some of the early C Dory's had plywood in their bottoms as a core material), is when you penetrate the core, with fasteners.

Fir is used in Marine ply. One of the reasons I specifically mentioned Okoume or Bruynzeel plywood is that these are higher quality than many other manufacturers use.

For example Homestead has marine plywoods in Douglas Fir, and CCA treated Fir plywood as well as other woods, including various hard woods and soft woods.

If you go to most lumber companies or even the big box stores like Home Depot, you will be buying Douglas Fir marine plywood. Not a thing wrong with it--My father built a dinghy out of douglas fir in 1936, and we gave it away after he died in 1986--50 years old and very usable.

 

[Sunbeam]

I'd go with Thataway's advice over mine, especially since I don't even have a clear mental picture of what you're building, or what your priorities or usage are (longevity, cost, weight, etc.).

I guess I was just reacting to what I sometimes see, which is that people just "fiberglass everything" without considering the possible negatives (or whether it is even needed). I've found decent plywood to be surprisingly long lasting in certain cases even without heavy-duty (and weight adding) treatment. Anyway... take my thoughts with a large grain of salt.

 

[AstoriaDave]

I believe Tom indicated he is using ordinary plywood, which around here is sometimes fir, but more often hemlock. Fir is more rot resistant than hemlock. Okume and meranti seem to be the most popular choices for so called marine plywood beyond the CCA treated fir plywood Dr. Bob cites. CCA treated plywood is available, but not through ordinary lumber outlets such as Home Depot, etc. Here is one source for CCA plywood; bring lots of Benjamins! http://www.pontoonstuff.com/cca-treated ... ywood.aspx All this fancy plywood costs a lot more than ordinary fir or hemlock plywood. With the protection Tom plans to use, I expect his deck boards will hold up very well.

In any case, glass on both faces will make it more long lasting and somewhat heavier. The ends of the deck boards need extra heavy epoxy treatment because they are "end grain" and will wick up resin, but are very difficult to glass because the glass will not bend around the edges to give overlap with the glass on the faces. Probably an annual cleanup with sandpaper and a little bleach, followed by another coat of resin is good enough. It will take a while for any edge rot to become a structural problem. Any isolated areas of rot can be gouged out and filled with epoxy and glass fibers, sure to outlast us all.

 

[bshillam]

One of the epoxies I found very easy to work with is MAS, it doesn't blush and doesn't require any sanding in between coats. It really makes the job that much easier. It might be a few bucks more but in the over all cost of the job it won't add anything to the project. Depending on temp of the shop you may need to use a faster set hardner check out their website. Being winter I would use medium, careful with the fast set as it sets almost the second your done stirring. As well, the nice thing about their set up is the pumps. They dispense the right amount of resin and hardner. No measuring needed!

 

[starcrafttom]

so this is the rear floor of my 16 ft valco river sled. last owner had covered the floor with some sort of bed liner material that has came off and I power washed as much as I could. As you can see the cross supports that are part of the floor make for a uneven surface. The old floors were 3/4 inch ply with thin carpet over it.

As you can see here I have pulled off the ply wood seats and removed all the foam. I found a 13 gallon tank and will replace what foam I can. under the forward seat, same as this one, I will place the two batteries and more of the foam. This will get the tanks and batteries off the floor and out of the way.


these two shots are of the floors and seats that I have cut out and will be glassing. Also a close up of the ply wood that I am using.

These floors will be taken out and moved around a lot to clean the boat. They will be getting wet a lot. Most of the water will be under the floor boards and draining to the back of the boat. So its two seats, and three floor sections. Its a pain to do but after its done it will be great. The old section that was in the back of the boat, about a half sheet of ply, weight almost a 100 lbs. This is going to make the boat a whole lot lighter and user friendly. Happy to answer any questions about the boat or the project.

I could only get poly resin at he local boat shop. I may go to WM and see what they have.

 

[AstoriaDave]

Wow. You have done a lot of grunt work already. Is that 3/4 inch ply? Yeah, as rough as the cross supports are, I would glass the underside, for sure. Also, try to saturate the edges of those panels with straight epoxy. They look pretty porous, so they should take up a lot of resin, probably three coats, and likely the resin will penetrate quite a ways, giving you good edge protection.

Are you planning fasteners to immobilize the panels? If so, make the holes for those before glassing and saturate them with resin, also. Some folks get fancy and counterbore to put the fastener heads flush, but that opens up a route for water to penetrate. A devil's choice.

Those panels look very manageable. I was thinking you might have some really long ones. If you decide to seal the panel to panel contacts, Lexel caulking from the hardware store is a good choice, as it remains flexible and a Stanley utility knife down each seam will release them for removal. I think this will be a pretty good glassing job.

BTW, consider mail order from System Three. I am sure they can beat WM prices, and the service is very good. Woodworking shops will carry WEST or System Three, also. I have found S3 at Rockler and another one whose name escapes me, in PDX. Crosscut Hardwoods in PDX carries some System Three epoxy materials, also. Definitely hold out for epoxy resin. Polyester resins do not adhere well to wood, and when the wood gets wet, expect the polyester to delaminate easily.

 

[Captains Cat]

BTW, consider mail order from System Three. I am sure they can beat WM prices, and the service is very good. Woodworking shops will carry WEST or System Three, also. I have found S3 at Rockler and another one whose name escapes me, in PDX. Crosscut Hardwoods in PDX carries some System Three epoxy materials, also. Definitely hold out for epoxy resin. Polyester resins do not adhere well to wood, and when the wood gets wet, expect the polyester to delaminate easily.

Or, alternatively, if WM is close and you want to use them, find what you want on the 'net, print it out and take it there and they'll match the price. You will have to pay sales tax however, and depending on where the 'net store is, you may not have to. But you may have to pay shipping.

That's a good winter project!

Charlie

 

[localboy]

Tom, once you seal it consider using Kiwi-Grip. Easy application, nice looking, water-based and you can touch it up if it gets damaged. I used it in our splash well & swim step. You can get it at Fisheries.

 

[C-Dawg]

Great thread, Tom, and coincidently, great timing. I'm picking up a 16' all-welded Gregor sled today that I bought, and plan to do exactly what you are.

I've been in a few sleds that had their floors covered with rubber matting that's used in horse stalls/trailers. Great non-skid properties and easy clean up. However, I believe it's about 2.75 lbs/sq ft, so I gotta do some measuring and decide if that's too much weight to be adding.

 

[Sunbeam]

Or, alternatively, if WM is close and you want to use them, find what you want on the 'net, print it out and take it there and they'll match the price.

I don't believe this is WM's policy any more. From what I was told (and have read), WM's new price-matching policy is to only match prices from sticks-and-bricks stores that are within 50 miles of the store you are in asking for the price match.

I think store managers have some leeway, as I was able to get a price match to a physical store that was 70 miles away, but I would no longer count on them matching any Internet price unless/until the policy is changed again.

 

[starcrafttom]

That is correct, they no long price match the net.