$85 for a 5x5 1/2 in sheet!




You do not want to use veneered plywood. The grade of Baltic Birch you want is B/BB. A fair price is $35-$40.turbovolkswagen wrote:RI, I checked another place in ct and they quoted me $60 for a 5x5 that was veneered.
To keep the outside plus the same direction??Gregory East wrote:They explained why plywood is always odd numbers of plys in primary school woodwork class. I forget now.
It was a lumber yardGreg Plouvier wrote:BB does fluctuate. It's $28 right now here. Last year it went up to $65 for a bit. Don't buy it from a lumber "store". Find a yard. In other words they don't sell tools, garden supplies etc. - just lumber.
Go to the top of the class jjohnsonjjohnson wrote:To keep the outside plus the same direction??Gregory East wrote:They explained why plywood is always odd numbers of plys in primary school woodwork class. I forget now.
No, it was a den of thieves posing as a lumber yard.turbovolkswagen wrote:It was a lumber yardGreg Plouvier wrote:BB does fluctuate. It's $28 right now here. Last year it went up to $65 for a bit. Don't buy it from a lumber "store". Find a yard. In other words they don't sell tools, garden supplies etc. - just lumber.
AKA "Ali BB and the Forty Thieves"Bill Fitzmaurice wrote:No, it was a den of thieves posing as a lumber yard.turbovolkswagen wrote:It was a lumber yardGreg Plouvier wrote:BB does fluctuate. It's $28 right now here. Last year it went up to $65 for a bit. Don't buy it from a lumber "store". Find a yard. In other words they don't sell tools, garden supplies etc. - just lumber.
We asked the question in our last newsletter: Why does plywood have an odd number of layers (plies)?
Actually we said it always has an odd number, which isn’t entirely true. Some low grade plywood has an even number of plies. But do yourself a favor and stay away from that stuff.
To understand why plywood has an odd number of plies, first we’ll take a quick look at how it’s made.
Veneers are cut from the trees in thin layers. These layers will become the plies of the board. When the plies are layered and glued together, they are arranged at 90 degree angles to each other. This helps to keep the plywood from expanding and shrinking based on moisture in the environment. The alternating construction creates a board that is much stronger in each direction than a similarly sized board cut from a single tree.
Now that we have a basic idea of how the material is made, we can better understand why an odd number of plies is ideal. The short answer is: symmetry. We already know that the expanding/shrinking problem was solved by aligning the plies at 90 degrees to each other, but what about other problems like warping? Well if the plywood has an odd number of plies, it won’t warp*. It will have a middle ply, and that middle ply means the material is symmetrical. If a ply on one side of the middle is trying to warp the board, it will have the opposite force on the other side preventing it from doing so.
So there you go, it’s a pretty simple reason, but a reason that not many people think about. It reminds me of something I was taught while training: Whatever you do to one side of the board, do to the other. In some cases painting a board can cause it to warp. But if both sides are coated, you make the board symmetrical, and warping will be less likely.
*under extreme conditions it can still warp, it is wood after all.
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