Ya know. I've got plywood stored (vertically as I have to choice because of space) for months and it's always fine. It doesn't warp at all. The only ply that I've ever had warp is either pressure treated or plywood that was stood up at too much of an angle and sagged in the middle.

 

Throw a piece of cardboard on top or lean them against the wall.

A slight bow with a piece that big won't matter because it should have something pulling it straight in assembly.

 

Thanks y'all. Yup, in full sheet form I also have to stand them on edge. And while I haven't had much issue with bowing, I didn't want this to be a first. Also, for sure, they are going to be connecting front and rear face frames for chests of drawers, so they should be good in that regard.

 

FWIW - I put them elevated on cardboard/wood (not to let moisture from the ground seep in) on edge against the wall and not on end (widest part horizontal) to reduce potential sagging, a few weeks you should be quite fine.

 

If you're worried about footprint, I suggest standing on end and if you're not worried about space I'd stand them on end...

Then sacrifice wall cosmetics and drill some holes (in the wall) and place at least two braces across full width (4-6 feet) to brace against the wall… at the top and in the middle, and flush it up against the wall at the bottom… Unless its 3mm sheets it should not warp and if it is, move some thicker stock to the outside. A few minutes shuffling when needed saves having to buy new/unwarped.

Also suggest some sort of water resistance underneath, whether needed or not… I use a piece of 19mm x 90mm treated pine (ripped).

 

Interesting. So y'all are saying storing the panels I have trimmed down on my workbench will cause a warp? Or are these suggestions on what to do with full size sheets?

 

Purchased about five 4×8 sheets of pre-finished 3/4 maple plywood for some cabinets.

Cut them to various sizes and laid most flat for storage for later use (on the floor, over a felt and plastic liner), while some others (the smaller sizes) were stood up, almost vertically. Since that time, almost every one has some bend to them, regardless of the orientation stored. Except for two pieces, the larger ones were reasonably easy to straighten when constructing the carcasses. The smaller ones have been almost impossible to flatten out as they suffered the most warp.

I think the orientation (unless stood at such a low angle against a wall) is less relevant than the humidity conditions. Mine were stored in a basement room, but with marked humidity changes over the last months.

Marv

 

Interesting. So y'all are saying storing the panels I have trimmed down on my workbench will cause a warp? Or are these suggestions on what to do with full size sheets?

- Phalanx1862

I don't think that's what we are saying. I think youll be fine, but losing your work bench space. Point is either would suffice for that period of time

 

This is how I store my plywood, and have for years with no problems. If you have the room to do so, store them on their sides against the wall and sit them on something (if nothing but a couple of 2×4s).....Less warpage that way.

 

Alright, I appreciate the help folks. Definitely with the full sheets, and most of the time cutoffs, I have them on edge against a wall. Actually, I have a pressure treated 4×4 as a footer for my lumber rack, so they have full edge support. My main curiosity was the panels I cut to size already. Losing my workbench top while they sit there isn't a big deal, as sanding them is the next step in the project anyways.

 

yeah i store all my ply full sized and cutoffs againts a wall with no problems with warping at all.some for years.

 

+1 all the above.

Just be sure to keep the plywood from touching concrete floor or walls. Concrete/brick/block holds and wicks moisture out into wood. Something as simple as couple 2×4 cut offs raising the panels off the floor stops most warping problems when stored on edge against wall.

Cheers!

 

I have a vertical cart on wheels that will hold around 20 sheets of 3/4 plywood. So I have to drive 120 miles to get to a quality hardwood supply house in Riverside CA. so when I make the trek, I buys enough for today and long term projects. So I store this in a sea container that gets pretty hot in the summer, but for sure dry. just pulled out a sheet of Honduras Mahogany that has been stored for 10+ years, and was perfect still.

 

Flat good, vertical can be a problem.

For a part like what you describe keep them on a table I'd possible. Stickers not really necessary if your shop is not climate controlled, cover the stack with a drop cloth.

Vertical is the logical way to go unless you have a lot of space. The key is to support the sheets and keep the bottoms pressed tight to the stack.

 

Nice y'all! Thanks so much for the help! I checked the panels laying on the bench last night, and they didn't seem to turn into potato chips on me. I was just trying to be cautious before I ruined $100 in plywood. I realize that as far as plywood goes, 50 bucks a sheet isn't the MOST expensive, but still didn't want to let 2 sheets go to waste.

 

It all depends on the humidity in your shop. I don't buy plywood until I need it. Usually I will stand a piece of plywood against a wall as vertical as possible and hop to use it before it warps. I have seen plywood in the big box stores warped 12" even when stored flat. The quality of the plywood is also a factor as well as the thickness. Thin plywood seems to warp more easily. It would be nice if the humidity could be kept the same day in and day out. Wood will always be susceptible to changes in the weather beyond our ability to deal with it.