Working with winding sticks could hardly be simpler: just place them across opposite ends of the lumber you wish to check, step back, and have a look. The board's surface must be fairly flat; setting a stick on a crowned surface wouldn't help much. Set each stick square across the board. Setting them askew will show twist that might not be present. To establish good contrast for maximum visibility, orient one flat side and one beveled edge toward you. If the background is bright, put the light-colored flat side closest to you, so the black bevel beyond will show clearly. Against a dark background, reverse the setup. Step back several feet and sight across the top edges of the two sticks, directly along the length of the board. Any twist will show as a wedge of black or white above one end or the other of the front stick. It's worth marking the high corners of the board to keep track of what you've seen as you prepare to true the surface on a jointer or with a hand plane.

STRAIGHTEDGES
To use the sticks as straightedges, let the beveled edge be your reference, with the bevel facing you. The shadow under the bevel makes light coming through beneath the edge much easier to see than it would be otherwise. If either stick becomes damaged or otherwise needs truing, it can be planed readily with a sharp hand plane, or it can be run over a jointer with sharp knives set for a very shallow cut.

BAR GAUGES
The sticks can be used together as a bar gauge, an adjustable measuring stick for comparing inside diagonal measurements to verify that boxes, carcases and frames are square. Hold the sticks' flat faces together with beveled edges up, so the beveled ends face in opposite directions. Slide the sticks past each other to nest the ends firmly in the corners of the piece you wish to check. Hold them firmly or secure them with spring clamps, lift them carefully from the piece and check the other diagonal.

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