Replies

1. 
   jonsherryl | Dec 10, 2003 07:25am | #1

   Doc, I'm sure if you do a search on one of the search engines, you'll come up with an industry association(s) that will be happy to help...But I can get you this far: In hardwood plywoods, the "A" refers to the quality of the face veneer, while the "1", "2",  or "4", etc. refers to the back veneer. Softwood plywoods are graded a little differently in that both outer veneers are given alpha grades, such as "AC", "AD", "BC" etc.

   I'm no longer current on what defects each grade designation allows in different types of plywood and I suspect it varies all over the lot by species. Even the allowable thickness of the face veneers varies by species in order to conserve supplies of the scarcer woods. With highly ring-porous woods, they can cheap-out only so far, but with some of the fine textured, diffuse-porous woods, they've got "paper thin" down to a real science.     

1. 
   Sphere | Dec 11, 2003 01:30am | #3

   Man Jon you said it, Paper thin is thicker than the last batch of Maple I had used. I completed an entire display/ Cash out area of a hair salon using mostly 5x5 baltic birch..(about 30 sheets) then my supplier showed me some that was now in 4x8..perfect for the computer desk /cash register area which was 7' long..well it was 13 ply, but the face veneer was actually more like maple than the other birch. That was not much of a problem with the sealcoat on it all looked the same..but, when I was edging it with the solid bullnose..nightmare..no room for any error..cant sand it, scrape it..nuthin. I could actually see the next ply through the face ply..I wish I had not taken his word for it and looked at it in better light before I bought it...buyer beware.

1. 
   jonsherryl | Dec 11, 2003 05:57am | #4

   Baltic birch ply comes from Europe. A lot of it is now produced in Russia...so I guess there's something to be said for being backward. Most of the 4X8 birch and maple is either domestic or Canadian and our mills on this side of the Atlantic are state-of-the-art when it comes to cheating.  :O)

   ---

   ...Also, the reason the domestic ply appeared to be more maple-like is that we use hard birch veneers over here...usually either yellow birch or sweet birch. The European birch is a softer species, much more like our norther paper birch and it doesn't have quite as much surface luster.

   Edited 12/10/2003 9:59:26 PM ET by Jon Arno

   Edited 12/10/2003 10:07:26 PM ET by Jon Arno

1. 
   Sphere | Dec 11, 2003 03:43pm | #5

   Jon, that was a very good explanation..tho' he made it sound as if it was a new size of the same stuff, I surely knew better when I began working with it..good to know the russians are making a better product than we over here are. The $ per sq.ft. was about even. I would have stuck with the 5x5 if I did not need a 7' desk top.

   Thanx for the info.

2. 
   HowardAcheson | Dec 10, 2003 06:05pm | #2

   Go to the Forest Products Labratory Handbook at http://www.fpl.fs.fed.us/documnts/FPLGTR/fplgtr113/fplgtr113.htm

   Click on Chapter 10. It will give you all there is to know about plywood and composition materials.

   You might want to look at the other chapters also. It's a great source of information.