Re-decking my boat and need help!

[MwBowhunter]

Now I know that this has probably been discussed a million times on here and ya'll are probably real tired of having it posted....BUT i have a 16' Sea Nymph "Fishing Machine" and I'm in the process of redecking it. Floors were rotten in spots and carpet was shot so i figured I'd rip it all out and start over. Found out that beyond the crap carpet and the rotten flooring the genius who previously redecked this boat had used spray foam, probably from a can, and laid the flooring before it was expanded completely. Now for my question....what am I doing?! This is my first time, so I have absolutely no clue what I'm doing. Foam is water soaked near the transom, so should I rip all of the foam out front to back and have it professionally resprayed? Next question is for the decking, I know I'm going to be using marine grade plywood but what do I do to it? I've read that I can paint or water seal it, but I was told if I wanted to do it right, not to do that and resin it. If I resin it, which i probably will, what do I buy? Next onto carpeting...should I have the carpet pre-cut and lay it before the resin is dry. or wait and glue it down? Any input would be greatly appreciated! Tips, tricks, and pointers are welcome!

Thanks in advance,

MwBowhunter

 

[Chris1956]

Your post is a bit confusing. All the foam should be under the gunwales or deck. It sounds like you have something else. In simple terms, cut out the deck, dig out the wet foam, and inspect the stringers and frames. Replace what needs it, glassing the new components into place. I like to use dry pressure treated dimensional lumber for stringers and frames. Now, mix up the two-part marine foam and pour it into the voids between stringers and frames. After it hardens, trim it to allow the new deck to fit. I like to use dry 1/2" pressure treated plywood for the new deck. Lay some fiberglass cloth (saturated with catalyzed resin, over the frames and stringers, lay the deck down and screw thru the plywood into the stringers, with stainless wood screws. Now saturate the deck with resin, and lay two layers of glass cloth over it and fill the weave with resin and let her harden. Obviously you want to glass the deck to the hull sides to make it all strong and waterproof.

 

[jigngrub]

Start removing wet foam at the transom and work your way to the bow until all wet foam is removed, you'll probably end up removing all of the foam.

You can replace the foam yourself and it'll be much cheaper than having someone else spray it in. You can use the 2 part expanding urethane foam or the extruded polystyrene rigid sheet foam insulation.

If you're going to spend the money on the top dollar marine grade plywood, I suggest you use epoxy resin to seal it. Epoxy (not polyester) resin is the best sealer. Use the 2 part marine grade and multiple coats... I like 4 coats.

Use a good solvent based carpet adhesive to glue your carpet to your decking before you install it in the boat. Wrap your decking panels with carpet and then install it by screwing it down through the carpet. The carpet knap will hide the screws and you'll be able to remove your decking later without having to rip up your new carpet.

 

[jigngrub]

Your post is a bit confusing. All the foam should be under the gunwales or deck. It sounds like you have something else. In simple terms, cut out the deck, dig out the wet foam, and inspect the stringers and frames. Replace what needs it, glassing the new components into place. I like to use dry pressure treated dimensional lumber for stringers and frames. Now, mix up the two-part marine foam and pour it into the voids between stringers and frames. After it hardens, trim it to allow the new deck to fit. I like to use dry 1/2" pressure treated plywood for the new deck. Lay some fiberglass cloth (saturated with catalyzed resin, over the frames and stringers, lay the deck down and screw thru the plywood into the stringers, with stainless wood screws. Now saturate the deck with resin, and lay two layers of glass cloth over it and fill the weave with resin and let her harden. Obviously you want to glass the deck to the hull sides to make it all strong and waterproof.

This works fine for fiberglass boats... but I believe the OP has an aluminum boat which is a different animal when it comes to resto.

 

[Georgesalmon]

yeah, every sea nymph I ever saw was aluminum. Don't use any pressure treated wood! Epoxy is a good sealer as are other methods found by searching here. You need to remove all the wet foam and replace with new. Where are you going to have it "professionally" sprayed? Best to buy your own two part kit and "pour" it into where it goes, or, use the blue stuff you can buy in 4 x 8 sheets. FWIW, I would use 2 part polyurethane cause its approved by the coast guard, all you need is 2lb denisity. Best carpet glue for boats is weldwood contact cement for both wood and aluminum. Put the carpet down while the glue is still a bit wet instead of letting it dry completely. JMHO

 

[MwBowhunter]

Chris- Sorry I'm just as confused with all this as my post is! But actually everything, except down the center of the boat where the plumbing for the live well is ran, is foamed.

Jigngrub- Found out not all the foam is ruined...should I go ahead and rip it out anyways or leave it? What brands of epoxy resin and glue would you consider? Any one better than the other?Another thing is that I was told I could lay the carpet right on the resin, is this a good idea or not? For the plywood, 1/2" since I'm going to resin it? Will I need to sand the epoxy resin down for the glue to stick? And yes, this is an aluminum boat, I apologize for not stating that.

George- I was going to have it sprayed by a local who owns his own business and builds boats for a living. He was going to spray waterproof closed foam sealant in the boat....found out today that it was going to be quite pricey with as much foam as there is. Where can i buy the foam to "pour" in? Since I don't need much, can I just use the spray can like from Walmart, or do I need to stay away from that stuff?

Thanks Ya'll,

MwBowhunter

 

[jigngrub]

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Jigngrub- Found out not all the foam is ruined...should I go ahead and rip it out anyways or leave it? What brands of epoxy resin and glue would you consider? Any one better than the other?Another thing is that I was told I could lay the carpet right on the resin, is this a good idea or not? For the plywood, 1/2" since I'm going to resin it? Will I need to sand the epoxy resin down for the glue to stick? And yes, this is an aluminum boat, I apologize for not stating that.

George- I was going to have it sprayed by a local who owns his own business and builds boats for a living. He was going to spray waterproof closed foam sealant in the boat....found out today that it was going to be quite pricey with as much foam as there is. Where can i buy the foam to "pour" in? Since I don't need much, can I just use the spray can like from Walmart, or do I need to stay away from that stuff?

Thanks Ya'll,

MwBowhunter

Like I said earlier, start removing the foam at the stern of the boat and don't stop until you get to completely dry foam. Some of the foam may seem dry and ok on top but it'll be wet on the bottom. If you find completely dry foam you can leave it in, I'd remove all of it. Removing all of your foam will let you do a good leak test and you'll be able to Gluvit all of the seams and rivet heads.

I would not recommend using epoxy resin for carpet adhesive. Use the Dap All Weather carpet adhesive instead:
http://www.amazon.com/Weldwood-All-Weather-Outdoor-Adhesive-1-Quart/dp/B000BQUG9I

... or Dap contact cement is another good choice:
http://www.homedepot.com/p/DAP-32-fl-oz-Weldwood-Original-Contact-Cement-00272/100125525

I like to sand my epoxied plywood with 120 grit, just enough to dull the finish and knock the shine off between coats and before applying carpet adhesive, it gives the next coat or glue something to grab.

If you plan to install pedestal seats I suggest going with 5/8" or 3/4" plywood decking. 1/2" isn't strong enough for pedestal seats.

Stay away from the canned foam, by the time you buy enough cans to foam your boat you could've paid the guy to foam it for you and have money left over. The canned foam isn't a very high density either and isn't very water resistant.

 

[Woodonglass]

There's always the option of using the Blue Or Pink SLAB foam from the Big Box Stores. It will never absorb water, easy to cut to shape and fit and readily available. Easy to remove if and when needed.

 

[MwBowhunter]

Okay, after this weekend I'm definitely going to have to rip all the foam out...sposed to get some pretty good rain all weekend. After I rip the foam out, should I put it on the lake for the leak test or fill the hull with water? If there are any leaks I will gluvit...can I buy this at any hardware store or will I have to go to a marine shop? When I put foam back in should, what should I use? Is the slab foam good enough or should I just use the pour in foam? Also how thick should I make it? If 1/2" isn't thick enough, I'll use 3/4" instead. Just wanting to do it right the first time. Should I put anything on the bottom of the plywood and what about the sides and cut edges?

 

[jigngrub]

Okay, after this weekend I'm definitely going to have to rip all the foam out...sposed to get some pretty good rain all weekend. After I rip the foam out, should I put it on the lake for the leak test or fill the hull with water? If there are any leaks I will gluvit...can I buy this at any hardware store or will I have to go to a marine shop? When I put foam back in should, what should I use? Is the slab foam good enough or should I just use the pour in foam? Also how thick should I make it? If 1/2" isn't thick enough, I'll use 3/4" instead. Just wanting to do it right the first time. Should I put anything on the bottom of the plywood and what about the sides and cut edges?

You want to stuff or pour as much foam as you can get into your boat, foam is like money... you can never have too much of it. If you go with the sheet foam, use the 2" thick sheets. The 2" foam will require less cutting which = less time to install.

To leak test your boat remove all of the foam and clean the boat out real good, then level the boat the best you can with the trailer tongue jack. Then fill the hull with a few inches of water and keep an eye on your trailer tires to make sure you don't over load with water weight. Look under the boat for drips and leaks, mark them if you find any. Let the boat sit for another hour and recheck for more drips or leaks. Lower the tongue jack so the water moves to the front of the boat and do another leak check, after that raise the jack and check the rear of the boat for leaks.

You'll have to go somewhere that carries marine supplies to find gluvit or coat-it (they're about the same thing), some walmarts carry them and academy sporting goods carries it too... or you can order it online. The gluvit looks better because it's clear, coat-it is black and will look like someone smeared tar in your boat... but it's cheaper than gluvit.

When you seal your decking, seal both sides and all of the edges... pay special attention to the edges and seal them real good.

I like the 635 thin epoxy resin, it penetrates well and is easy to work with. 4 coats is like a sheet of Lexan covering your plywood. It's very tough, durable, and long lasting.