plywood drying.

[oops!]

im just about to run out and get some plywood for the trans/stringers.

using ac grade ply...was going to use pressure treated. but the resin wont sink in to it..

if anyone knows better ....nows your chance to talk me out of ac for pressure.


here's the quest.....

i intend on drying the plywood in a garage by a wood stove a few days before i start cutting..... can i do any damage to the wood if i dry it too quick? the wood stove puts out a lotta heat.

thanks
oops

 

[rockyrude]

Re: plywood drying.

The only reason resin won't stick your the p.t. is because it is wet. Dry the ply kind of slowly away from the heater or it'll turn into a "potato chip". If doing more than one sheet, put spacers between them so air can get around all sheets evenly.

 

[Bondo]

Re: plywood drying.

The only reason resin won't stick your the p.t. is because it is wet. Dry the ply kind of slowly away from the heater or it'll turn into a "potato chip". If doing more than one sheet, put spacers between them so air can get around all sheets evenly.

Ayuh,......

And,.....
Keep moving,+ rotating the pieces.... That way it won't dry too quickly on 1 side or another....
Them keep them near the Woodstove After you make the Cuts......
Smaller pieces dry Quicker.....

I did a refit in 1998 with P/T,+ Epoxy...... No Problems Yet.....

 

[Chris1956]

Re: plywood drying.

Oops, I recommend solid pressure treated lumber for stringers. They do delaminate like plywood. PT plywood is good for the floor, dry it as suggested. use SS or Silicon bronze fasteners to attach the floor to the stringers and to attach the stringers to each other if applicable.

 

[BillP]

Re: plywood drying.

The reason for NOT using untreated ply is it ROTS. PT ply doesn't rot and resin DOES stick to it. It's been used the last 20 +yrs in the boat mfg industry...for stringers, transoms and floors. The American Ply Association did tests that show poly sticks to PT (cca process)as well as it does to untreated ply (they found zero difference). The test info is nothing new was on their web site in a pdf file going back at least 5 yrs. It has to be dry but otherwise polyester sticks to it.

 

[Coors]

Re: plywood drying.

I used MAP epoxy on my stringers, and will never touch poly again.

 

[SgtMaj]

Re: plywood drying.

Give it at least 2 weeks to dry, and put a dehumidifier in there with it... heat alone won't do it, the air surrounding it needs to have a lower humidity than it has, otherwise no matter how hot you get it, it will absorb water from the air.

 

[oops!]

Re: plywood drying.

awwwww man !

i thought i had this down pat!!!!!!

thanks guys...bond-o

gonna re read stuff...
and hang out at the auction for a de humid!!!!
i was hoping a good squrrel cage fan would be good (sp...its late)

keep it comin
cheers
oops

 

[SgtMaj]

Re: plywood drying.

Well, you could always put it in with slightly higher water content. They say 12-17% is best for wood anyway.

 

[Robj]

Re: plywood drying.

Use Doug Fir PT ply. Cut it into strips and lay it on the floor on some 2x4's for air circulation and put some weights on top so it won't twist. It will take close to a month for it to dry. Try and get CCA treated ply, it is better and easier on fasteners that ACQ. PT is the way to go, I did lots of research on this when I did mine and I agree with BillP. When I tried to delaminate a layer of glass from the wood, the wood failed not the bond.

Have a great day,

Rob.

 

[BillP]

Re: plywood drying.

Use Doug Fir PT ply. Cut it into strips and lay it on the floor on some 2x4's for air circulation and put some weights on top so it won't twist. It will take close to a month for it to dry. Try and get CCA treated ply, it is better and easier on fasteners that ACQ. PT is the way to go, I did lots of research on this when I did mine and I agree with BillP. When I tried to delaminate a layer of glass from the wood, the wood failed not the bond.

Have a great day,

Rob.

I did some sample tests that did the same thing...but also did a ton of research on pt for boat use over 10 yrs ago and likely will never use untreated ply again. Basically, old pt processes used petroleum products...resin won't stick to the old processes. The only place I found those old pt processes with petroleum being used was on railroad ties... nothing else. The later pt processes (CCA & ACQ) have nothing in them (except water) to prevent adhesion. The people who make pt marine ply dry their panels before leaving the factory. Those of us who use homedepot pt have to do the drying ourselves. I dried some pt about a month and other pieces over a yr inside my shop and most of the parts were cut first to help speed it up. It never warped but I set old car batteries on top and flipped it every so often to help keep it straight.

 

[oops!]

Re: plywood drying.

rob.... a month? with a wood stove?

aaaaaarrrrrrrrggggggg!

ok.......

ive got all the old wet stuff laying beside the stove and its drying out nicely

(used for templates)

cheers all
oops

 

[rockyrude]

Re: plywood drying.

Sorry oops,
the closer you get your drying stack to the heater the more trouble your going to have. You see the idea is to get it to dry flat and straight. The close heat will cause one side to dry faster than the other, sometimes it happens fast enough that the inner layers actually crack weakening the piece. Don't cut your templates until they are dry, they can shrink as much as 1/4" from wet to dry.

 

[Robj]

Re: plywood drying.

That is how long I had mine inside, it is more damp here than where you are, so yours should dry out faster. I would not leave it beside the stove though, it may cause irregular drying and warp. Keep it in a warm, area and you should be good to go in about 3 weeks or so. You could used a fan to speed things up. Try and find the CCA treated like I said in my previous post, it is better than the ACQ. Whatever you do, DO NOT BURN the scraps. The ashes are TOXIC, the CCA contains arsenic. Just throw them in the garbage.

Have a great day,

Rob.

 

[SgtMaj]

Re: plywood drying.

Use Doug Fir PT ply. Cut it into strips and lay it on the floor on some 2x4's for air circulation and put some weights on top so it won't twist. It will take close to a month for it to dry. Try and get CCA treated ply, it is better and easier on fasteners that ACQ. PT is the way to go, I did lots of research on this when I did mine and I agree with BillP. When I tried to delaminate a layer of glass from the wood, the wood failed not the bond.

Have a great day,

Rob.

Why cut it into strips?

 

[Robj]

Re: plywood drying.

Why cut it into strips?

The stuff he is using for stringers so it will dry faster. Maybe I should have said, cut to the rough dimension for what you will be using it for. You should have no problem letting the floor dry, the stringers will keep you busy for a while.

Have a great day.

 

[oops!]

Re: plywood drying.

got it last nite.

pt caa d fir . $550 for 8 sheets

.stoked the wood stove before i left.....

man it was hot in there.. 8 beer hot!

wood is 15 feet away from the stove.. im building a drying bracket today.
and putting a squrrel cage by it.

so now its back to the grinding......

cheers
oops

 

[BillP]

Re: plywood drying.

Use a fan to blow air around the panels...they will dry faster.

 

[drewmitch44]

Re: plywood drying.

i called the factory and they have seasoned dry PT ply that they think is no good. Im getting mine from there. Its about a 30 min drive but it is dry PT wood. They have all ranges of wood that they measure with like a moisture meeter computer and probe. Im not wasting time and money with wood stoves and de-humidifiers and all that non-sence. why not just buy the ply with like between 11-17 moisture. I dont want ot too dry though but they have all the ranges of dry to moist for sale. Just my 2 cents. Think people are better off calling the lumber yard directally and you will get what you need and not spend so much time playing with yourself.

 

[oops!]

Re: plywood drying.

i agree drew....

we got lots of major lumber mills around here....5 within 1 hr drive

prob here is they all store outside....its winter here...rain..sno...cold.

everything is wet...and effin it aint...it will be by the time you get it home!

best o luck to ya....

im off to do some more grinding now.....

have a good one

oops