# Marine Grade Ply



## nicdicarlo (Nov 8, 2007)

Does anyone know if they sell Marine Grade Plywood at the HomeDepot/Lowes? If not, does anyone know a good substitute or a place that carries it? I would be looking for 3/4". Thanks.


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## Captain Ahab (Nov 8, 2007)

Try a real lumber yard - not Home Cheapo


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## bassboy1 (Nov 8, 2007)

Any real lumber store will have it. But, you probably don't want it.

First of all, it is 85 bucks a sheet. May be more by now - that was a year and a half ago. I would recommend getting the higher grade (has footballs only on the outside ply) exterior grade ply from lowes, and giving it a good coat of oil based paint on all sides, ESPECIALLY THE EDGES.


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## nicdicarlo (Nov 8, 2007)

Thanks. 85 bucks a sheet is too much for me, at least for the application I want to use it for. Thanks for the info.


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## Waterwings (Nov 8, 2007)

> ...I would recommend getting the higher grade (has footballs only on the outside ply) exterior grade ply from lowes, and giving it a good coat of oil based paint on all sides, ESPECIALLY THE EDGES.



My recommendation also. Get the edges real good.


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## Jim (Nov 8, 2007)

Good to know! thanks for the info!


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## pbw (Nov 9, 2007)

Isn't there a composite plywood out now days?


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## bassboy1 (Nov 9, 2007)

pbw said:


> Isn't there a composite plywood out now days?


With composites, there is no need for a ply, as it can be formed into whatever shape. Plywood is make from thin plys, that were actually curved around the tree. I mean, the wood was basically unrolled, then flattened, and glued together, with the grain going the opposite way. They can't unroll a 3/4 inch piece, so they have to glue many together. Composites can be made however thick they want.

But, at this point, many of the composites are not practical for boat use. To heavy, or not strong enough, and often too expensive. 

Aluminum is a great choice for decks, but it can get a little pricey.


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## micropterus (Nov 9, 2007)

Pressure treated and marine grade plywood is corrosive to aluminum. You have to be careful that there is no direct contact between that kind of wood and bare aluminum.

Like eveyone else has said, usually plain plywood with a waterproofer will work well. I use that for the floor of my boat. With a carpet adhesive on top of the water proofer, it's about as water-resistant as it gets.


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## bassboy1 (Nov 10, 2007)

micropterus said:


> Pressure treated and marine grade plywood is corrosive to aluminum. You have to be careful that there is no direct contact between that kind of wood and bare aluminum.


Marine ply is not pressure treated. It is regular ply, made with a better species of wood. Also, there are a lot more thinner plys. Also, all the knots, and voids have the little footballs in them. Not just the top ply, like the better grade HD ply.


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## redbug (Nov 11, 2007)

Nick, I used pressure treated plywood on my crawdad. it was still in mint condition after 6 years I also treated it with Thompson's water seal as added protection. I covered it with indoor/outdoor carpet and it ooked good.

Wayne


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## nicdicarlo (Nov 11, 2007)

Thanks for all the info guys. I'm going to visis the Crawdad today, take some measurements, and layout a flooring sceme. I priced ply yesterday on a quick trip to lowes, but the selection/description of each variety wasn't that good. I didn't see any pressure treated, although maybe they keep it with the pressure treated stock. I'll check it out next time. 
Currently, I plan on getting a higher construction grade 3/4" plywood that is resonably priced and coating it with either a few coats of oil based paint or some type of sealant. I'm not sure if I am going to go with carpet or just grip tape.


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## shamoo (Nov 11, 2007)

I dont know if this will work or not, dont know the price or even what its called, I've seen docks made out of these and I dont believe it would take too many to pieces to floor a craw-daddy, its that wood made out of plastic, maybe you could floor it like a boardwalk and youd never have to worry about it again, perhaps run the pieces the width of the floor.


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## micropterus (Nov 11, 2007)

bassboy1 said:


> micropterus said:
> 
> 
> > Pressure treated and marine grade plywood is corrosive to aluminum. You have to be careful that there is no direct contact between that kind of wood and bare aluminum.
> ...



The marine grade plywod I've seen is still treated with waterproofing agents that are corrosive to bare aluminum.


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## Waterwings (Nov 11, 2007)

What if you used some decent Exterior grade ply, and then coated it with some good exterior oil-based sealant?


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## micropterus (Nov 11, 2007)

Waterwings said:


> What if you used some decent Exterior grade ply, and then coated it with some good exterior oil-based sealant?



That works - it worked in my case at least. If you ware using it for flooring, make sure it's good and dry before applying carpet adhesive.

I would use a decent A/C grade plywood. One side (the A side) would be smooth and a good surface for applying carpet using carpet adhesive. The C sides wouldn't be seen. 

By the way, I never did catch what the original poster wanted to use it for. I just assumed it was for flooring.


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## nicdicarlo (Nov 11, 2007)

Rowland, I'll be using it for a new floor in my crawdad. 

As for the "plastic wood" that they use for decking, its great, super durable but its pretty dense and heavy, not to mention pricey. If weight wasn't an issue, it would be a good boardwalk way to go.


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## nicdicarlo (Jan 2, 2008)

Ok, I've got my floor design done for my crawdad and I have my new tools, I'm ready to cut. I plan on using 3/4". I originally wanted to make a floating floor, but since the boat will likely be stored upside down, i think I'll be securing the floor to the support beams in the bottom of the boat with selftapping screws. Regardless of that, I don't plan on using carpet. Instead I just want to use some type of griptape/traction pad on the areas I'll be walking on. Before I apply that though, I need to seal the wood. I've heard of using wood sealant or oil based paint. I would prefer to use a sealant, but wouldnt be completely opposed to painting. Does anyone have any specific products/brandnames they can recommend? Thanks.


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