Just wondering which is the best postprocessor to use in FreeCAD. Since Onefinity’s controller is a fork of Buildbotic’s controller and Buildbotic’s controller understands code which is patterned after the LinuxCNC dialect, I first though I should use the LinuxCNC postprocessor (Path workbench → Job → Output tab → Processor). But Carl and Lynn uses the GRBL processor, possibly because of this?
I thought I’d seen an earlier post asking a similar question that also got zero replies. Maybe it’s a faux pas? IDK. Anyway, I tried it and:
- I’ll be using GRBL
- Running LinuxCNC output file starts with a prompt to hook up the probe. Once it gets a touch and you click continue, it begins cutting.
- The GRBL output doesn’t prompt for the probe - it moves straight into cutting.
Although it looks like the actual motion portion of the generated gcode was identical in the 2 files, the differences are:
GRBL GCode inserts the following on every line
K0 - Turn off Linear Advance
G54 - sets the work offset zero location
G49 - cancel tool length compensation
G80 - cancel all active canned cycles
G40 - turn off cutter compensation
M5 - stop spindle rotation
M6 T2 - Toolchange
G54 G80 G40
I’ve been using the LinuxCNC post processor for over a year. I didn’t mess with the post amble (G54 G80 G40) but I have on occasion gone into G-Code files and modified height settings for the milling bits - only reason being is my negligence in properly defining all the detail for the mill bits, depths & heights in the job.