Autofokus laser head on a K40? oooh yes :) Is it needed? - Modifications - Maker Forums
I have decided to upgrade my K40 by building a new frame supporting the XY rails and to increase the cutting area to 620mm X 450mm | K40 Laser Cutting Engraving Machine
Lengthen the K40 X-Axis linear guide rail : r/lasercutting