# Plywood warped/Why?



## jules (Oct 25, 2014)

Hello, well...what happened here? I have ply standing upright outside and not warping. I left this piece on the saw horses overnight and it warped, like a "record coming out of an oven"!


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## APBcustoms (Oct 26, 2014)

Did it rain?


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## JR Custom Calls (Oct 26, 2014)

I was going to suggest dew.

Reactions: Like 1


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## jules (Oct 26, 2014)

Yes there was dew and fla humidity. Outdoor ply at 33 dollars.


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## APBcustoms (Oct 26, 2014)

The reason I ask is because the plywood being on the saw horses allowes air to flow underneath which can super dry it also it maximizes sun so my guess is it soaked up moisture and then was super dried this can cause warping but also Gravity is pulling down in the middle which causes stress. So my guess is a mixture of the stress of gravity and the evaporation of moisture. I like to use marine ply wood because it has a ton of glue in it and is more water resistant


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## CodyC (Dec 4, 2014)

Looks like a sheet of BC plywood...from a home center? If so, you are lucky you made it out of the store without it warping.
Seriously, though, you should not leave unfinished plywood outside, especially in a horizontal position. The near-100% humidity that occurs in early morning will wet it and result in the warping you see when it dries.


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