• The first is Rotary Cut. A log is spun on a roller and a big knife peels off the skin of the log. (Just like peeling an apple).
• The other is Flat Sliced. The log is sliced into long thin slices lengthwise. (Just like slicing a carrot from head to bottom)
   

The plies are then sandwiched together with a resin (glue) and pressed with enormous pressure. The plywood is then cut into standard 4’ x 8’ lengths. Sometimes, depending on the customer needs the sheets can be as big as 4’ by 20’ long. If the plywood has more plies, such as, Baltic Birch Plywood, it makes it very stable.

There is also many types of plywood, including:

• Cabinet grade, for making kitchen cabinets, furniture, woodworking projects, etc.
• Sheathing, used for siding on homes.
   
• Marine plywood has a waterproof resin so it can be used for boats and exterior uses.
   

Plywood is graded by how many imperfections it has. If the plies were clear with no knots, dents, discolouration, it would be considered as Select, #1 or A Grade. If there were plenty of knots and holes it would be lower down on the scale and be called a Shop or Utility grade. For some people, if they’re working on a project and the appearance is not necessary, they choose a “middle of the road “ grade.

When was plywood first developed and what is some background history?
True plywood requires at least three layers of veneer stacked so that the grain alternates 90 degrees. The veneers are cross-layered and joined together by an adhesive.

The 1993 Hardwood Plywood Reference Guide, a publication of the Hardwood Plywood & Veneer Association states that, "in 1830, the piano industry became the first North American industry to use plywood. Wood & Wood Products Magazine's Centennial issue (1996) says that, "in 1890, the rotary cutting process was invented," and as a result of mechanization, plywood became increasingly affordable.
In 1929 a pamphlet published by the National Committee On Wood Utilization noted, "Plywood is a modern term describing an old product which did not receive serious technical and economic consideration until its adaptability to airplane and marine consideration was developed during exhaustive tests at the Forest Products Laboratory."

The word "plywood" which was created in America, received official sanction in dictionaries printed a few years later. That's plywood... veneers on the other hand, dated back to the early Egyptians in the times of the Pharaohs... about 4,000 years ago.

How much does a sheet of plywood weigh?
Plywood weights will vary according to species and even country of origin. A "ball Park" number for North American made softwood plywood would be 23 lbs for a 4 x 8 x 1/4" sheet.

What is the difference between Luan Plywood and regular good-one-side plywood?
Good one side is a recognized grade for Canadian made Fir plywood. This panel is obviously made from Fir veneer and bonded on exterior grade resins. The face is well sanded, repairs and natural defects (knots, splits, etc) are limited. For further info try the Canadian Plywood Association, www.canply.org/.
Laun is a term to reference a group of wood species. Laun plywood's come in a variety of grades, some of which are similar to Good one side. Launs are usually bonded with interior grad resins and are not equal to Fir plywood in structural strength.

What type of wood and sizes do you offer for scroll saw hobbyists?
The ideal wood for scroll saw work is Baltic Birch. This special plywood is constructed with more veneers per unit of thickness than other types of plywood. Manufactured in Europe, this panel is ideal for routering, scroll sawing or for applications requiring high stability. Available in 5' x 5' sheets and thickness 1/8”, 3/16”, 1/4”, 3/8”, 1/2”, 3/4”. Prices are from $12.00(1/8) - $60.00 (3/4") per sheet.

Plywood Grading
SHEATHING: Generally broken into 4 grades.
SELECT: Should be solid face, can allow some veneer splits, no wider than 1/16” knots are allowed, but must be sound and tight, not more than 1-1/4” in diameter.
STANDARD: Face will be made from “C” veneer, can have knot holes in face thru 1st layer of veneer only, knots are limited to 1-1/4” in diameter.
D GRADE: All fall down from above, including some face or back veneer missing or loose.
CULL: Allows for any possible imperfections - delimitation, off square or miss sized

MEASURING LUMBER
What is the difference between a linear foot and board foot?
A linear foot is a measure of length 12 inches long and a board foot is a number calculated by determining the volume of a board that is 12 inches wide and 1 inch thick. In other words, a 1" x 6" board that measures 24" long is exactly one board foot. (width" x thickness" x length' / 12)

How do I figure out a board foot?
To convert linear feet to board feet: Thickness” x Width” x Length’ ÷ 12
To convert board feet to linear feet: 12 ÷ Thickness” x Width” x Board Foot

LUMBER
What are Hardwoods and Softwoods?
The degree of hardness has no bearing on whether the wood is a hardwood or a softwood. Hardwood was the lumber cut from deciduous or broad-leaved trees that produce enclose seeds such as Cherry, Maple, Walnut, Oak, etc. Softwood was the lumber cut from coniferous or needle-bearing trees that produce free unopened seeds such as the cones of Fir, Cedar and Pine.

Why does bird’s eye occur in different kinds of wood?
It hasn’t been proven conclusively what the actual cause is, however it is known that it only occurs in trees which undergo growth stress from competing with surrounding trees for light and nourishment.
Studies have shown that a tree which has developed bird’s eye at an earlier stage of its life will no longer develop the figuring in future growth if the trees around it are cut down. Nearby maple trees that also developed bird’s eye continued to do so if the neighbouring fauna was left undisturbed.

The dimensions of rough cut lumber determine the lumber's nominal size. This can be misleading to a novice when lumber is referred to in sizes which are not the actual dimensions. So how does it work?
After surfacing, a board might be reduced by as much as 1/4" on each side but it will still be identified by the nominal width. This is the Erosion a nominal 2" x 4" board, a "two-by-four", is actually only one and one half by three and one half inches in size. Here are the nominal and actual sizes for most common lumber: A nominal 1" x 2" is actually 3/4" x 1-1/2. a nominal 1" x 6" is actually 3/4" x 5-1/2", a nominal 2" x 4" is actually 1-1/2" x 3-1/2". Most construction lumber is supplied in lengths of eight, ten, and twelve feet.

Is it better to paint a big project piece by piece or as a whole assembled together?
Piece by piece is always the best way to get full coverage and to avoid painting around hardware, etc.

I've been building furniture, mostly out of pine, and I've been very disappointed to find that after a project is finished the joints become loose and some of the pieces no longer fit properly. I suspect that it has something to do with humidity. What do I do?
Wood is an organic substance and expands and contracts with changes in humidity... always has... always will! The secret is to work the wood only after it has adjusted to local conditions. Every workshop should be equipped with a storage area where wood can be air dried. Wood should be purchased well in advance and it's moisture content should be in a 7 to 12% range. You can usually be assured that the wood is not to wet if it is sold as "Kiln dried", however even then it is a good idea to let it air dry in your shop for a while. Following these procedures should minimize shrinkage and splitting.

When did chestnut trees disappear?
Chestnut blight has devastated North American stocks over the past 20 years. Wood from infected trees is of no commercial value. In an effort to contain the spread of the disease there are severe restrictions on the cutting and transportation of the timber.

FLOORS
The hardwood floors were previously done with a high gloss finish. It is starting to peel in sections, how do I fix it?
You should sand it all and refinish it.

How can you make Douglas Fir floors look good again?
They can be sanded and varnished to look their best again.

Can you install a layer of T&G plywood over a 3/4” plywood subfloor? Should the T&G run in the opposite direction and what is the best way to nail the T&G connection point?
You can install T&G over 3/4” plywood subfloor. It should run across the subfloor and it is best to use flooring screws. The usual application schedule is 6” spacing around the perimeter and 12” on the field.
 

How do I fix a squeaky hardwood floor?
The squeak is probably in the subfloor over a floor joist. Best way is to run screws into the subfloor through the joint nearest the squeak. If this is awkward, first screw a 2 x 2 to the side of the joint tight to the subfloor, then screw up through the 2 x 2 into the subfloor.

I would like to know who manufactures the "glueless" Viva-clic laminate flooring. Also can you give me the results of the Taber testing on it?
It is made in Germany by Holz Dammers Moers. Taber testing alone is no longer considered to be a reliable measure of abrasion resistance as results can be easily manipulated. It should be considered only when included in a battery of other tests conducted by an independent testing facility. Viva has been given a Class 23 (residential) and class 31(commercial) rating in such tests.

Can you use Oak plywood as a "Hardwood" flooring?
Don't even think about it. The veneer is only 1/48" max thick and can't tolerate abrasion unless given several coats of special floor finish. The main reason not to, however, is that the core veneer of the cabinet plywood are allowed voids, which could cause a furniture leg or a shoe heel to pop through, ruining the floor and perhaps cause an injury. Use products that are intended for flooring.