WORKING WITH THE GRAIN
Many woodworking tasks, especially planing, require working in the direction of the grain. You can usually tell grain orientation by running your hand along a board face: The surface will feel smoother when your hand is moving with the grain and rougher when running against it. Another method is to slide a smoothing plane lightly along the face in one direction, then repeat in the opposite direction. The blade will chatter or catch on the wood fibers when it is cutting against the grain. As shown on the plain-sawn board at right, the wood fibers slope “uphill” in the direction of the grain and “downhill” against it.
To prevent a plane blade from catching the grain and tearing or chipping the wood fibers, always cut in the uphill grain direction. This will produce clean shavings and a smooth surface. Be especially careful to spot grain that changes direction within a single board. The diagram at left shows several typical grain patterns with arrows indicating the best planing direction. The uphill direction may be constant from one end of a board to the other (A). Or it may change, demanding that you plane from each end toward the middle (B). It could also change from the middle to the ends (C). If the grain does not slope at all, you can plane in a single pass from either end (D).