Pen depth setting tool for v-plotter/polargraph machine

This is a pen depth setting tool for my Gondola and pen holder (pen collar).

The idea is that you set one pen to the correct depth and use that to set the depth on this tool. Lock the tool with the locking screw and you can then quickly and easily set the correct depth of the other pens.

See http://www.thingiverse.com/thing:1393028 for pen holder (pen collar) and push fit Gondola.

See http://www.thingiverse.com/thing:1393182 for a pen holder to hold multiple pens in their individual pen