Engraving all three Tek Circuit Computer decks on a single sheet of styrene plastic with the diamond drag tool:
The three patterns overlap here & there, but the intent was to have plenty of engraved lines for further study:
The vivid blue glare comes from a flashlight at grazing incidence off to the left, with brutal color correction back to something sensible.
Engraving each deck at a different depth gave a range of downforce:
EZ='EngraveZ=-0.5mm' Runit Bottom Engrave EZ='EngraveZ=-1.0mm' Runit Middle Engrave EZ='EngraveZ=-2.0mm' Runit Top Engrave
I fed all three of those G-Code files into bCNC, applied them to the same sheet with the same origin touchoff, and it worked fine.
The tool holder rate of 200 g + 50 g/mm produced downforces of 225, 250, and 300 g. In retrospect, the range wasn’t really broad enough, so Moah Force may be in order.
The diamond produced plenty of swarf:
Wiping the surface with a strip of masking tape clears away the loose rubble:
The innermost scale comes from the top deck, engraved at 300 g. The long shadows from the plastic pushed up along the tick marks seem to indicate the deepest trenches, although I don’t have any way to measure their depth.
I scribed and snapped the sheet into quarters so I can (mis)treat the engraved patterns in various ways:
What a mess!