Warped 1/4" ply for cabinet backs?

[Walter McNeil]

Hi all,<br><br>I'm building some base cabinets from 3/4" domestic birch ply. &nbsp;I've got a couple of sheets of 1/4 domestic birch ply I had intended to use for backs, but they are somewhat warped and won't lay very flat. &nbsp;I've got the first one temporarily screwed into the 1/2" rabbety to keep the box square while I get the rest built.<br>These sheets were curled from day1; I think it's because they are only birch laminated on one side and have reacted to Houston humidity. &nbsp;The hardwood supply didn't let me pick and choose...<br>Should I attempt to flatten these out, or just go try to find some better 1/4" material?<br>It may not be too much of a problem with the smaller cabinets, but the sink base is 5' along the wall. &nbsp;I have a scrap of 1/4" ply about 2' long I've considered gluing up behind the main back, in the middle. &nbsp;I could turn it around so it opposes the main bow and that may take up a lot of it.<br>What do y'all think? &nbsp;Can I expect this 1/4" to lay flat, or should I just screw them up against the wall and not worry about it?<br><br>Thanks,<br>Walter

[Don Wacker]

Hi all,<br><br>I'm building some base cabinets from 3/4" domestic birch ply. &nbsp;I've got a couple of sheets of 1/4 domestic birch ply I had intended to use for backs, but they are somewhat warped and won't lay very flat. &nbsp;I've got the first one temporarily screwed into the 1/2" rabbety to keep the box square while I get the rest built.<br>These sheets were curled from day1; I think it's because they are only birch laminated on one side and have reacted to Houston humidity. &nbsp;The hardwood supply didn't let me pick and choose...<br>Should I attempt to flatten these out, or just go try to find some better 1/4" material?<br>It may not be too much of a problem with the smaller cabinets, but the sink base is 5' along the wall. &nbsp;I have a scrap of 1/4" ply about 2' long I've considered gluing up behind the main back, in the middle. &nbsp;I could turn it around so it opposes the main bow and that may take up a lot of it.<br>What do y'all think? &nbsp;Can I expect this 1/4" to lay flat, or should I just screw them up against the wall and not worry about it?<br><br>Thanks,<br>Walter

Id use 1/2 backs and just use the 1/4 for the drawer bottoms.

Don

[Jeff Duncan]

Are you using separate nailers to secure the cabinets?

I use either 1/2" or sometimes even 3/4" for backs as I'm not a fan of fabricating seperate nailers. If you are using separate nailers then I wouldn't worry about the 1/4" warping, when you staple it to the 3/4" it will pull it flat enough. If your not using separate nailers then I wouldn't use 1/4" as it has virtually no structural holding power.

good luck,
JeffD

[Walter McNeil]

Thanks guys. No, I won't be attaching by the 1/4" back. I've got a 3/4"x4" top rail inside the back for wall attachment.