I’ve been using the Z-axis of my CNC machine to lift the pen from the paper during jogs to new drawing locations, but these very small movements of .05 inches or so have severely worn a single tooth in the pinion gear which moves the Z so it will have to be replaced… In order to avoid such uneven wear in the future, I developed a solenoid operated pen lifter which also significantly speeds completion of the drawings, as the solenoid lift and drop is almost instantaneous while the Z moves much slower… “Shea” involved about 5 million lines of movement code including over 100,000 pen lifts — seems to work quite well!
"Shea", Dec. 4, 2006, 77x45, pen and ink drawing
"Shea" detail
The mounted pen assembly in operation
Detail showing simple pen guide (a small hole)