Quick plywood question

[voodoolord]

My deck was 5/8 plywood and Im having a hard time finding 5/8 around here. Is it a big deal to go up to 3/4? Are there any drawbacks besides added weight? Thanks.

 

[idonthaveaname]

Re: Quick plywood question

Shouldn't be a problem.

 

[74bayliner]

Re: Quick plywood question

Shouldnt be a problem. i dont see how it could hurt except for maybe a little extra weight but i dont think it would matter much.

 

[kfa4303]

Re: Quick plywood question

+1. I used 3/4" on mine and it worked great. I suppose it weighs a bit more, but not a whole lot and it's very solid. Make sure it's not pressure treated (if it's and aluminum boat) and seal it with some epoxy, f'glass or spar urethane/porch paint and attach all wood to the hull using stainless steel hardware and/or aluminum rivets dipped in 3M 5200 marine caulk/sealant. Aruaco (sp?) is a popular brand of non-PT, exterior grade plywood that is available at most Lowes/HD. You can also get your stainless hardware, aluminum angle, pink/blue insulation foam for flotation, and 5200 at the big box stores. About the only thing they don't have are the epoxy/f'glass supplies, but they usually carry the Spar Urethane and/or Porch Paint. Rustoleum Professional Oil based Enamel is also good stuff. If you have a West Marine nearby they carry spreadable 2-part epoxy. It's a little pricey, but you wouldn't have to have it shipped and it will seal the decks for all eternity.

 

[cb4hunter]

Re: Quick plywood question

+1. I used 3/4" on mine and it worked great. I suppose it weighs a bit more, but not a whole lot and it's very solid. Make sure it's not pressure treated (if it's and aluminum boat) and seal it with some epoxy, f'glass or spar urethane/porch paint and attach all wood to the hull using stainless steel hardware and/or aluminum rivets dipped in 3M 5200 marine caulk/sealant. Aruaco (sp?) is a popular brand of non-PT, exterior grade plywood that is available at most Lowes/HD. You can also get your stainless hardware, aluminum angle, pink/blue insulation foam for flotation, and 5200 at the big box stores. About the only thing they don't have are the epoxy/f'glass supplies, but they usually carry the Spar Urethane and/or Porch Paint. Rustoleum Professional Oil based Enamel is also good stuff. If you have a West Marine nearby they carry spreadable 2-part epoxy. It's a little pricey, but you wouldn't have to have it shipped and it will seal the decks for all eternity.

y not pressure treated it last longer.

 

[kfa4303]

Re: Quick plywood question

The metal preservatives (Copper and Arsenic) in pressure treated lumber will react with the aluminum hull and cause pitting in your boat. While stainless steel is also a dissimilar metal from the aluminum in your hull it will not cause the same galvanic reaction as the metals in the pressure treated lumber.

 

[jigngrub]

Re: Quick plywood question

Pressure treated lumber is evil voodoo for aluminum.

If you want a long lasting decking plywood and don't mind paying a little more use HDO (high density overlay) or MDO (medium density overlay), it's used in boat building, sign making, and concrete construction. It is waterproof, very tough and has few if any voids. It should be available at one of your local lumber yards of specialty wood yards.

If you don't want or can't find MDO you can seal your plywood with 2-4 coats of epoxy resin to waterproof it for a long lasting build.

As far as switching from 5/8 to 3/4" decking, it's not a problem unless you have a lot of hatches built into your deck. If your hatches covers are 5/8" thick the 3/4" won't let them lay flush with the decking and you may have a problem with your hatch cover hinges as well. These problems can be overcome by mortising out for your hinges and shimming your hatch covers... but it is more work.

 

[voodoolord]

Re: Quick plywood question

Great info guys. Thanks.

 

[rickryder]

Re: Quick plywood question

I'm just curious.... where you from voodoo? No lowes home depot or lumber yards out your way? 5/8 ply is always in stock in those places... Like everyone said 3/4 is fine...bit more weight but your deck will be real firm

 

[voodoolord]

Re: Quick plywood question

I'm just curious.... where you from voodoo? No lowes home depot or lumber yards out your way? 5/8 ply is always in stock in those places... Like everyone said 3/4 is fine...bit more weight but your deck will be real firm

Im in So. Oregon. We have lots of lumber yards but I was planning on using pressure treated ply and couldnt find any in 5/8. Im on the fence now about the pressure treated because its more expensive and Ive been told that with it being poly coated it should last another 35 years. The old deck wasnt covered on the bottom and made it that long.

 

[Woodonglass]

Re: Quick plywood question

Is this a Glass or Aluminum Boat??

 

[voodoolord]

Re: Quick plywood question

Glass