Wood and cork

A sawmill is the only factory whose raw material arrives in a shape nobody chose, and every decision it makes is about fitting rectangles into a circle that tapers. So the pattern is drawn here rather than tabulated: a sawyer arguing about a cant thickness is arguing about a shape, and a column of numbers has never settled that argument. Two things then run through everything. The first is that recovery by volume and recovery by value disagree, and it is the second that pays wages — a pattern that yields more cubic metres of the wrong grade is a worse pattern. The second is the dimension chain, worked backwards from the customer's rule: the board is measured planed and dry, so it must be sawn oversize by the planing allowance, the shrinkage and the saw's own variation. Sawing to the number on the order is the most expensive mistake in the trade, because nothing reveals it until the timber is dry, planed, sold, and measured by somebody else. Drying is held to the same standard: a charge run faster than the species allows carries damage that no moisture meter shows, and a load whose wettest and driest boards are far apart is not dry, however good the average looks.