glue used in birch plywood

[subman]

Could anyone tell me what type glue is used in birch plywood and more importantly would you use it for sub roadbed where hardshell type scenery is to be used or do you think that the moisture in the hardshell will cause delaminations?

                                        Thank you

                                     Bob D

[Don Z]

Bob,

I used birch plywood for my benchwork decking and I haven't had any problems with delamination due to moisture from applying plaster or scenery materials. I don't know what type of glue is used in making birch plywood, but I think it would take much more moisture than what your scenery will contribute to cause any delamination in the plywood.

Don Z.

[subman]

Thanks Don . No one here sells 5 ply 1/2 inch except marine grade plywood  and CDX and the BC 4 ply at Home Depot & Lowes does not store their sheet goods on level racks so there is a curl to them that I couldn`t even straighten out with the wheels of  a truck on the curl overnight so I brought them back. Fir plywood is almost impossible to get around here unlike out West or up North so what are we left with? hardwood ply or SYP hence the question about birch.

[jeffrey-wimberly]

The glue is water-based. Don't worry about your plaster scenery delaminating it though. My layout extension is 3/4" birch veneer plywood which sat outside for a month or more and hasn't peeled apart yet.

[subman]

Well Jeffrey if the plywood took that sought of a beating I know il`l be using it . I was left 5 2x8 sheets of it and need 1 more 4x8 sheet but was undecided whether to use it until now.

[jeffrey-wimberly]

Yeah, I know about that birch plywood. I've helped build a LOT of office furniture with it. I have a homemade birch plywood bookcase in my back room that measures 4 feet high, 4 feet wide and 2 feet deep. It's made with 3/4" birch ply and deck screws.

[lvanhen]

1.  DON"T buy plywood at Home Despot or Lowes - they don't know how to store it!!  Drive around to the back of the store and see all the lumber that is stored OUTDOORS!!!

2.  Plywood has a grade stamp on it. AB/sanded is 1 A side (no imperfections) and 1 B side ("football" plugs allowed)  INTERIOR GLUE.

3.  CDX has 1 C side - fairly rough - and 1 D side - pretty bad - the X means exterior glue.

4. Marine grade birch ply has "water resistant" glue - better than exterior but not "water proof".

5.  You probably won't find anyone at HD or Lowes that has a clue as to what a grade stamp is or means!!

6.  Go to a lumber yard - pay a couple of bucks more but get something that is GOOD!!!  My