P-lam onto Baltic Birch ply

[David Wyson]

Hello

About to skin 3/4” Baltic Birch plywood cabinet doors with plastic laminate. Doors various sizes but most about 16” by 26”. Doors are JUST the plywood….exposed edges. It is a nice quality, void-free ply.

I have done a fair amount of laminating of BB CABINETS, but never a “floating” panel like this.

Questions:

1. I think it is (used to be) standard practice to laminate BOTH sides of the panel, to prevent warpage. Is this the case?

2. If laminating both sides, it seems that if you do not do both at the exact same time, you could still get warpage. As the first side dries, won’t it pull up on the surface just a bit…..is that what causes any warpage? Again…is it important to skin both sides quickly?

3. Can one side just be coated with water-based poly, and the other side plastic laminated? Will this balance the sheet? And….must do both sides quickly?

Thanks for any advice.

David
Seattle

[Paul F Franklin]

You do want to laminate both sides. You can use backer grade laminate for the backs if you don't care what it looks like, since it's usually a lot cheaper. I usually do both sides at the same time. I apply adhesive to one face, flip it over onto painters pyramids or the like and apply adhesive to the other side to the other side. But I have done one side at a time too, with no ill effects. In that case, I applied adhesive to one side, waiting the drying time, applied the laminate, and then immediately did the other side. No idea how long you could delay before getting into trouble. I think the safe way is to do both sides at once.

Don't know about just sealing the back with poly; my gut says it won't work to balance the door, but I don't know for sure. Doors are such a bad place to deal with warping, I've always played it safe.

[jack duren]

Trying to think of why he needs to apply to both sides of plywood?

[John TenEyck]

Trying to think of why he needs to apply to both sides of plywood?

To avoid warping due to non-uniform moisture gain/loss.

John

[John TenEyck]

If you solvent based contact cement, you can do one side at a time, in reasonably fast succession, since there's no water involved. If using yellow glue, etc., stuff with water, then I would do both sides at the same time.

John

[jack duren]

Can’t say I’ve ever seen a problem not doing both sides of plywood or melamine..

[Mark Gibney]

David, if you have the time perhaps do a test of different combinations and let us know what you find?
And of course beware that BB plywood is frequently not flat to begin with.