you need

4 gears, two for each gear box. 4 racks 2 gearboxes 2 clamps

Held together with 3mm screws/nuts.

I originally created this to aid in drilling multiple drawer pulls but it could be used for anything that need to be centered between parallel sides. Due to a slight calculation error, the center is a half millimeter off, but this is more than close enough for drawer pulls.

The rig holds replaceable drill templates. Included are Templates for standard drawer pull for metric and 1/2 inch increments from 0 to 4 inches. A blank template is also provided so you can easily generate your own.

To use for drawer pulls, determine the correct template to use (screw the pull to the template). Place a small bit of painters tape on the drawer, locate the horizontal center and mark it on the tape.

Place the rig on the drawer, pull the top and bottom to fit, and align the notch with your center mark, Drill.