This is the first post of an ongoing series about wood. Understanding its nature, the way it moves and changes, and the implications for designers and builders. Check back every Wednesday for the next installment.
Here's a dangerous assumption we might make about wood: That is once it's cut it remains, more or less, the same. But this is not the case. Even after being cut it moves; it expands, contracts and warps. And this movement often results in dramatic alterations to (or completely ruins) the design of furniture or environments. Understanding the nature of wood is the first step to avoiding surprises, and it is crucial knowledge for a furniture designer to amass. Changes in humidity alone can remove or add as much as a quarter-inch from a board's width. Think about what that might do to your carefully-placed joints on either side of, say, a tabletop you'd designed, that was comprised of four boards glued together along their edges: if each board grew 1/4" in length during a humid summer, you'd have an inch overall of added width--and joint failure where the tabletop connected to the skirt or legs.
So to unpack wood, I'll start a few steps before the lumber finds its way into your shop. What goes into a sawmill is logs, and what comes out of it is boards. But turning the former into the latter is a more detailed process than one would think. Initially it's a geometry problem: We have one log and we want to cut it in such a way as to yield the most useable boards. Over the years, sawyers have devised three main ways to cut a board: Plainsawn, quartersawn and riftsawn.
In this series I will describe each cut—its advantages and disadvantages—and its best applications.
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