plywood drying.

BillP

Captain
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Aug 10, 2002
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3,290
Re: plywood drying.

If you're close to Washington state...Greenwood Products is there and makes the marine pt ply that most boat mfgs use.
 

Robj

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Mar 22, 2007
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1,441
Re: plywood drying.

Most PT ply is not kiln dried. I live 10 minutes from a plywood plant and they do not have any kilns. Don't know why, but I have never seen kiln dried PT ply at any lumber yard.

Have a great day,

Rob.
 

BillP

Captain
Joined
Aug 10, 2002
Messages
3,290
Re: plywood drying.

Check greewoodproducts dot com and go to xlpanels. They're the only ones I've found in the USA that make marine pt.

One of their blurbs...
Moisture Content: Kiln dried after treating in a controlled environment to 13 percent or less to assure uniform stability and flatness.
 

GregE

Petty Officer 2nd Class
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Jun 29, 2007
Messages
144
Re: plywood drying.

Check greewoodproducts dot com and go to xlpanels. They're the only ones I've found in the USA that make marine pt.

One of their blurbs...
Moisture Content: Kiln dried after treating in a controlled environment to 13 percent or less to assure uniform stability and flatness.

I have read that treated wood (regular everyday exterior use) is NOT advisable against aluminum. This would rule it out for an aluminum jon boat. But "treated" could be many different methods I guess, and I don't remember which type of chemical treatment wood is the no-no in an aluminum structure. Any ideas on this?
 

clemsonfor

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Sep 19, 2005
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1,011
Re: plywood drying.

Green products is not the only placer that makes marine ply, i guy i went to school with's (im a forester) dad owns a pole/ply mill which makes Marine plywood. Im not sure who thier buyers are but it is made here in SC and they are not greenproducts.com They do not use a kiln to dry B/c in the plywood process after they peel and cut the pieces to rough 4x8 they send it through a dryier before they lay them up and send them to the press. The only diff in the regular ply and Treated ply is the chemical. The treated wood goes to a vacumme chamber that pulls a vac. then the chanber is flooded with the chemical which is a water born chemical. So any way once treated the water in the wood from the process is what makes it wet and correct most places will not redry b/c of the money to do it. It has to be dried before treatment b/c the wood is already saturated and wood not soak up enough lbs. /cuft to be called marine ply. The two availible treatments are CCA (copper cromated Aresenate) (which in dimentional lumber was banned in the consumer market not commercial, like 20003or 04 (not sure about marine ply though) and ACQ (amoniacal copper quart) also a water born preservative like previously mentioned. This is (ACQ) the one that should not be in contact with steel or aluminum as it speeds up the corrosion process, like when used in deck construction the screws are special coated and will now say acq safe, i dont recall but think it is the quart part that is the corrosive part.


-Nate
 

BillP

Captain
Joined
Aug 10, 2002
Messages
3,290
Re: plywood drying.

I have read that treated wood (regular everyday exterior use) is NOT advisable against aluminum. This would rule it out for an aluminum jon boat. But "treated" could be many different methods I guess, and I don't remember which type of chemical treatment wood is the no-no in an aluminum structure. Any ideas on this?

That's kinda sorta correct but...PT is commonly used on aluminum...my 1996 MonArk alum pontoon boat was built with 3/4" pt for the deck. Since new it has hung in a boat lift over saltwater and still in A1 shape. They insulated the wood from the alum with a thin rubber gasket material. A thick barrier coat of epoxy will do the same thing. Bolts can be isolated with nylon bushing and nylon washers backing up the metal washers. My uncle did pt on his old Starcraft and used tarpaper between the wood and transom. That was probably 10 yrs ago and it's still perfect.
 

Robj

Lieutenant
Joined
Mar 22, 2007
Messages
1,441
Re: plywood drying.

I believe the ACQ treatment is harder on fasteners than CCA. CCA is still available, up here at least so that would be my first choice. Use SS fasteners regardless.

Have a great day,

Rob.
 

viking1978

Cadet
Joined
Jun 7, 2008
Messages
8
Re: plywood drying.

If it helps anyone in Minnesota or the TwinCities area. Shaw Stewart Lumber Co. in Minneapolis on Johnson street has kiln dried pressure treated ply in 1/2 and 3/4 thickness.

Matt
 
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