![]() ![]() However, it can also cause some woods-such as black walnut (Juglans nigra)-to lose the vibrancy of their heartwood colors, resulting in a more uniform and/or washed-out appearance.įor most woodworkers, running their own kiln to quickly dry lumber may be impractical or excessive. ![]() Kiln drying wood at elevated temperatures also has many other secondary effects as well, such as killing powderpost beetles (a destructive wood pest) in all stages of their development. This piece of red oak (Quercus rubra) exhibits honeycombing, which is among the worst of drying defects, both because it’s irreversible, and it usually can’t be detected by looking at the face of the lumber. In extreme instances of case-hardening, the core can split and check in an irreversible condition called honeycombing. Later, as the core eventually begins to dry and shrink, the condition is reversed, and the stretched shell prohibits the core from completely shrinking. ![]() If the moisture difference between the core and the shell is too great, the shell can dry in a stretched condition. This defect is caused when the outer shell begins to dry faster than the core: the shell tries to shrink, but is inhibited by the still-wet core. Thus, a kiln is able to dry wood much more evenly, and it’s this uniformity in drying that allows it to also dry the wood quickly-simultaneously avoiding the drying defects usually associated with rapid, uneven drying.īut kiln drying may also introduce internal stresses into the wood-particularly if an improper kiln schedule is used, or if corrective measures are not employed-resulting in a condition known as case-hardening. The main advantage of a kiln is that with the increased temperature and airflow-all while carefully maintaining and controlling the ambient humidity-the wood can be dried much more evenly, minimizing any sort of moisture gradient between the outer shell (which dries very quickly) and the inner core (which slowly equalizes moisture with the shell). While there are various types of kilns used to dry lumber, the basic premise is usually the same: a large insulated chamber or room is used to balance and control humidity, temperature, and airflow to safely and efficiently bring wood down to an acceptable moisture content. In situations where green wood is to be processed into usable boards, (especially in the case of thicker lumber), a kiln is frequently used to control the drying process. The traditional rule-of-thumb for air-drying lumber is to allow one year of drying time per inch of wood thickness this adage obviously only takes a few of the aforementioned variables into account, but it’s at least a rough starting point in understanding the time investment required in order to properly air-dry lumber. ![]() Drying times can vary significantly depending upon wood species, initial moisture level, lumber thickness, density, ambient conditions, and processing techniques. You’ll find that the longer the timber cures, the more difficult it is to strip off its “wrapper”.Allowing lumber to passively sit at a given humidity level in order to obtain a desired EMC (air-drying) may be the simplest and least expensive method of seasoning wood, but it is also the very slowest. Always debark your wood while it’s still green. With a little practice, you’ll soon be able to peel off two- to three- foot strips with one swipe. To use the spud, just anchor or wedge your post so it won’t move, stand over it, and dig in. Sharpen the business end of the device, and presto! You’ve got a tool that’s guaranteed to make easy work of any bark-stripping job. To make one yourself just take an old hoe, heat its “neck” until the metal is malleable, and bend the blade back until it forms a 165° angle with the tool’s handle. My debarker–I’ve also heard it called a “peeling spud”–is simply a garden hoe with the blade straightened out. Well, peeling the bark off those timbers doesn’t have to be a slow and tedious task. And you know that you should skin the bark off the posts with a drawknife (so that damaging insects, moisture, and fungi will have no place to hide)… but you’re tempted to sorta forget that part of the job, since bark stripping can be wearisome work. You’ve just cut twenty cedar fenceposts to replace those rotted ones along the edge of the south pasture. If you have an old garden hoe, you can easily create a handy log debarker.Īll right. ![]()
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