Options: Generic

pcb2gcode --help shows all the command-line options available.

millproject file

If a file called millproject is available, pcb2gcode will read options from it. This can be a convenient way to save the options together with the project.

Units

All options that have units of length, speed, time, etc, can be specified with units. Many common units are supported so if you just try a common one, it will probably work. Units must be correct, however, so "60mm" is not a valid speed. You probably meant "60mm/minute" or "1mm/s". You can mix SI and imperial units however you like and extra spaces are generally tolerated.

You shouldn't use parameters without units because it's confusing. For the sake of backwards-compatibility, they default to either inches or millimeters, depending if you specified the --metric=true option.

Miscellaneous options

Generic options (CLI and config files):
  --ignore-warnings [=arg(=1)] (=0)     Ignore warnings
  --svg arg                             [DEPRECATED] use --vectorial, SVGs will
                                        be generated automatically; this option
                                        has no effect
  --metric [=arg(=1)] (=0)              use metric units for parameters. does 
                                        not affect gcode output
  --metricoutput [=arg(=1)] (=0)        use metric units for output
  --g64 arg                             [DEPRECATED, use tolerance instead] 
                                        maximum deviation from toolpath, 
                                        overrides internal calculation
  --tolerance arg                       maximum toolpath tolerance
  --nog64 [=arg(=1)] (=0)               do not set an explicit g64
  --output-dir arg                      output directory
  --basename arg                        prefix for default output file names
  --preamble-text arg                   preamble text file, inserted at the 
                                        very beginning as a comment.
  --preamble arg                        gcode preamble file, inserted at the 
                                        very beginning.
  --postamble arg                       gcode postamble file, inserted before 
                                        M9 and M2.
  --no-export [=arg(=1)] (=0)           skip the exporting process

Mostly you don't need to adjust any of those. If you are doing something out of the ordinary with the settings and getting warnings, set --ignore-warnings to cause pcb2gcode to go ahead and make the output anyway.