I made a ruler out of plexiglass with a laser cutter to use on the bed of a Vandercook Universal I. The ruler spans the two bearers and the 0 of the ruler matches up with the bed of the press. I also have mounted a peel-and-stick metal ruler to the feedboard with the same zero. Even without the plexi ruler, this is invaluable for quick and accurate registration.
The tick marks and labels on the ruler were engraved as a vector graphic (rather than as a raster fill) and then filled with ink. Each letter and numeral were engraved as single-path curve and not as an outlined shape. As digital fonts require closed paths, I made a custom font that has an extra point for each glyph far above the cap height which closes the path. To convert the glyphs to a single path format, I outlined the type in Illustrator then direct selected every extra points all at once and delete it. Without this workaround, the other alternative would be to have the path reverse itself, but then the laser cutter (or any other CNC engraving tool) will go over the path twice.
