In this feature, Jim Koudys provides useful information to woodworkers who want to enhance their understanding of the wood with which they work. Here he answers questions that are most often put to him.

What is quarter sawn?:
Lumber or veneer pieces in which the growth rings form angles ranging from 45 to 90 degrees with the wood surface are considered quarter sawn. Other terms for such cuts include edge grain, vertical grain or radial cut. An attraction of quarter sawn lumber is that it allows the distinctive feature or ray flex in some species. This is especially evident in maple, oak, sycamore and beech. Another advantage of these cuts is more stability, because there is less shrinkage. Typically, quarter sawn is a more expensive cut because of the time involved in processing and the amount of lumber wasted to form the cut. As a consequence of these factors, quarter sawn lumber is usually more difficult to find.

What is moisture content?
Moisture content is determined by comparing the percentage of the weight of water in a piece of wood to the weight of wood when it is completely dried. The relative humidity where the lumber is purchased may be different than the humidity in your workshop area. You should climatize the lumber in the environment in which it is being worked to obtain the equilibrium moisture content (EMC) of the wood. While 72 hours of climatizing is generally recommended, 2 weeks or longer tends to achieve better results.

What is a board foot?
A board food is a piece of lumber that is measured in its rough state. Its dimensions are 12" x 12" x 1" thick. One board foot is 144 cubic inches of wood. (The calculation is length in inches x width in inches x thickness in inches divided by 144 = 1 board foot (bd. ft.).

What is the least expensive way to buy lumber?
There are several answers to this question so I'll try to answer it by going from the least expensive to the most expensive and let you find where it's best for you. The cheapest way may be to have your own logs milled by private sawyers. The cost of the board foot can go down to as low as 20 to 30 cents per board foot and the lumber will be milled the way you want. The next best thing is to find a mill that carries a supply of logs of varying species and grades. Depending on your project, you can purchase a log with as little as 75 to 400 board feet and hive it milled to your specifications. This can cost as little as 35 cents to $2.00 per board foot. depending on the species, grade and cut of the log. The next best thing is to buy lifts of green lumber. Some places offer green lumber by the lift. Your next best is to buy small quantities of green lumber which are more expensive than lifts, but still cheaper than seasoned lumber. The next is to buy dried lifts of lumber. You may be purchasing between 200 and 4oo board feet, but the cost savings may be there. The next is to purchase small quantities of rough dried lumber and dress it yourself. (This is where we do most of our sales.) This will range from $100 to $6.00 depending on grade and species. Next, have a mill dress it for you. Last but not least (well maybe least), go to your local commercial lumber store and buy completely homogenized wood at potentially outrageous costs.

I have a log to be milled and I have heard that 'through and through' is the cheapest way to have it milled.
Yes and no. Yes, 'through and through', which is a method of milling logs, is a fast and easy method to mill a log, but not always the best. A reputable sawyer will always try to suggest the best method of milling to yield the highest quality of wood for the lowest cost. That may be 'through and through' which is just simply cutting straight through the log. the sawyer may recommend sawing around the log (what we like to call best face milling). This method is slightly slower than through and through, but likely will yield the highest quality boards possible.

In my hobby magazine, I saw a project which needed the bark left on the piece of lumber. However every piece of lumber that I process, the bark fall off.
What time of year did you cut you log? Whether the bark stays on the log or not is largely dependent (in most species) on the time of its life cycle throughout the year. If you cut a tree down in the spring, summer or fall, the cambium (which is the layer just below the bark that either becomes bark or cellulose) is at the point of growth when the bark is loose form the tree. In the winter, the cambium layer is dormant and the bark is tight on the tree. So when a tree is cut in the spring, summer or fall there will be a tendency for the bark to fall off, while a tree cut in the winter will usually keep its bark on even after milled into lumber. This is by no means the best scientific explanation, but rather the simplest considering the space.

I've seen logs by the side of the road waiting to be cut, and they have been painted on the ends. Does this identify different grades of logs?
It may, depending on what you mean by 'painted on the ends'. More than likely it is what we call end grain wax. After a log is cut, the drying process begins and logs release moisture from the ends, at least 10 t0 15 times faster than from the side of the tree. The problems that arise from this is what is known as checking. Checking are those splits you see in the end of a log. They can go as deep as the length of the log. Using end wax, which may be purchased from some mills, will slow the drying and reduce the amount of checking.