Get equal spacing in seconds, with no math
Here's a dirt-simple and quick way to mark equal spacing along the edge of a workpiece. Simply mark parallel lines spaced 1" apart on a sheet of material, such as hardboard, that's flat, light, and sturdy.
Next, mark the centerline on the edge of your workpiece and align it with a line near the center of your marked sheet. Then, rotate the workpiece to adjust how far apart the marked lines intersect with your workpiece. No matter the angle of the workpiece, the spacing between an equal number of lines on either side of the workpiece centerline will always be equal.
—Paul DeJaynes, Mount Pleasant, Iowa