Or: Getting an actual shape from a drawing to the mill
OK so we've had the mill write something using the default LinuxCNC example code, but LinuxCNC is not for designing anything, it only runs G-code generated by a CAM or CAD package.
So, we've got more software and can now try and generate something “original” - in this case we're going to trace a picture in Inkscape, save it as SVG and use PyCAM to turn it into G-Code as described here.
Wrinkle
Inkscape translates a bitmap image by outlining both sides of the lines, which gives an unexpected double-edged result in the same way PyCAM does with regular fonts. There's ways around this which we'll no doubt get to later.
We went on the internet, and we found this!
Load into Inkscape, right-click, something something… trace bitmap!
Save as SVG.
Yes I forgot what I did here, will update later if I remember!
The wrinkle here is Inkscape has dutifully traced the inside & outside of the shape as two separate lines, so we're getting two separate tool paths:
Also note the shape is wherever it was on the A4 page in Inkscape - miles away from the machine's “home”. If only there was an easy button to fix that…
That's better - the shape now sits at X0,Y0,Z0.
Back later - stay tuned!