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!

Here are two photos of the controls mounted in the machine and working:

The mounted assembly in operation


Detail showing simple pen guide (a small hole)

Here's the completed pen and ink drawing of "Shea":

"Shea", Dec. 4, 2006, 77x45, pen and ink drawing

"Shea" detail

-- Mike Lyon

Labels: drawing

¶ 9:45 AM