Wood-working for Beginners: A Manual for Amateurs. Charles G. Wheeler
of the quality of the wood, so if you can find stock that you know has been seasoning for years by the natural process, buy it by all means for your nice work, even if you have to pay more, regardless of what the dealers in kiln-dried stock or the makers of articles for sale may tell you about the advantages of kiln-dried wood.
On the other hand, if a dealer brags of his new patent "chain-lightning" dryer that will make green wood "dry as a bone" in two or three days, go elsewhere to buy your stock, for wood dried in a few days is not the kind to use for good work. You will probably have to use kiln-dried stock for most, or, perhaps, all of your work, but get it from a slow-drying kiln and keep it for further seasoning as long as you can.
Even if wood has been well seasoned, it is best, before putting it into nice work, to cut it up and dress it approximately to shape and leave it in a dry place for some time for a final seasoning, particularly in the case of thick stock. Do this with kiln-dried stock fresh from the dry-house. Let it have a little time to get into harmony with the atmosphere. Whenever wood has been exposed to damp air, as in a wet shed or cellar, let it stand in the warm shop a while before using it for nice work.
The stock is arranged for seasoning so as to allow the air to circulate around and between the pieces. A common way is simply to arrange them in piles, each piece being separated from those above and below by strips or sticks laid across (Fig. 28). These sticks should be placed directly over one another, and so that the lumber will lie straight, else the weight of the pile, which should tend to make the pieces dry straight, will have the opposite effect and make them permanently crooked. There are other ways of arranging wood for drying, but this method is common and illustrates the most important principles. Stock is sometimes stacked upright, and small pieces are occasionally hung up for such nice work as billiard cues and bows.
Fig. 28.
Seasoned wood is lighter in weight than green, dryer to the touch, usually has a different odour, cuts differently when you whittle it (and the piece you whittle off breaks differently), and it shows a difference when you saw it. It is impossible to define these differences and you will have to learn them by actual work. It is not always easy even for an experienced person to tell with certainty about some pieces until he has "worked" them, so much do the characteristics of different pieces vary. One test is to rap the boards sharply with a hammer. A green board and a dry one of the same kind will "rap" differently—that is, will have a different vibration and give out a different sound. Of course this cannot be described, but you can judge quite well in this way. It is one of the many things you can learn only by experience. You can ascertain much about the character and condition of lumber by sawing or planing or whittling a piece. This is a good test for dryness, toughness, and elasticity (which you can tell about by breaking the shavings).
Weather-dried timber is usually somewhat darkened from exposure, but kiln-drying lightens the colour of some woods.
Stock with a bright lustrous appearance and of dark hue is generally superior to that of a lighter colour and duller appearance, but such characteristics depend much upon the kind of wood. Green wood is tougher than seasoned wood, but the latter is more elastic. To subject seasoned wood to moisture and heat brings it back, to a certain extent, to its original condition, and renders it for the time being tougher, hence the process of bending wood by the application of steam or hot water (see Bending in Part V.).
Reject "wany" lumber, or that of which the edges or corners have not been squared (Fig. 18), and also boards and planks which have not been sawed to a uniform thickness. It is not uncommon for a board to be considerably thinner than it should be in some part of its length, due to irregularity in sawing.
For plain work avoid "cross-grained" stock, as well as that having knots (which are sometimes "tight" and sometimes "loose"), as it is harder to work and to smooth, is not as strong, and does not hold its shape as well, as a rule. Sometimes it is desirable, however, on account of the beautiful figure of the grain shown in many crooked-grained pieces, as in mahogany for furniture (see Appendix). Bear in mind that when especial strength is required rift stock is best.
Reject wood which smells musty, or has rusty-looking spots, which are signs of decay, or of the attack of fungi, which may spread and under favourable conditions attack other pieces which are sound (see Appendix).
Fig. 29.
Fig. 30.
Reject crooked stock. The worst form is winding or twisting. Of course no one would take such an extreme case as Fig. 29, unless for some very rough work, but even a very slight winding may make much trouble in your nice work. So look particularly for this defect, which you can often detect at once by the eye, but if your eye is not well trained use winding-sticks (see Part V.). Warped or curled stock, with the surface rounded or hollowed (Fig. 19), is also bad, but you will need no instructions to detect this defect by the eye or any straight stick. When boards are rounding on one side and hollowing on the other, it is due either to the way the log was sawed, as we have seen, or to one side having been more exposed and so having dried faster and shrunk faster than the other, causing that side to be concave, while the other became convex. Stock is sometimes crooked lengthways—either a simple bending in a curve or at an angle, or wavy (Fig. 30), or both—often due to careless "sticking" (Fig. 28) while the wood was green. Sighting lengthways will of course show these defects.
Reject stock badly checked at the ends, or cracked. There is apt to be more or less of this in most lumber. In seasoning, the pieces dry faster on the outside than in the middle, which causes checks or cracks, usually worse at the ends of the pieces, where the drying takes place most rapidly. The ends of valuable boards and planks are sometimes painted or cleated, which in a measure prevents this result. Occasionally, when the cleat is removed a crack will suddenly extend and even split the board.
Do not take a cracked or partly split board, thinking that you can use the sound end from the point where the crack appears to stop. Possibly you can, but oftentimes and in some kinds of wood it is impossible to tell before the stock is cut where the cracks end. In mahogany, for example, they sometimes are found to extend, or develop, several feet beyond where they appear to stop. Sometimes you can buy wood with such defects at a discount. Unless you are sure, however, that there is enough sound, clear wood outside of the cracks or knots, and unless the discount is pretty large, it will usually be better to buy clear, sound stock for nice work, as the waste is very apt to offset the saving, not to speak of the extra time and labour it takes to work up such material. (See Shakes in Appendix.)
Reject sapwood as far as possible, because it is usually inferior to the heartwood.
In the case of elm and young ash the sapwood is, however, superior to the heart. The heartwood is usually harder and more durable than the sapwood, heavier, of better texture, and commonly of better colour.
"The sapwood is, as a rule, darker in the whitewood class than the heartwood, whether seasoned or unseasoned, but is paler in colour in most hardwood trees which have had time to season. In some of the white, or softer woods, when fresh cut, the difference is scarcely perceptible; but exposure to the air quickly gives to the outer layers a greenish tinge, due to a species of mould fungi which attack them."—Laslett and Ward. (See also Appendix.)
When buying, do not take boards just as they happen to come from the pile. Select them yourself. Most good-natured dealers will let you do this if you do not expect them to unstack a whole pile just for one or two boards.