pcb2gcode - command-line tool for engraving PCBs using CNCs

       pcb2gcode was written by Patrick Birnzain, loosely based on an earlier program of the same name  by  Jeff
       Prothero (Cynbe ru Taren), which in term was based even more loosely on Matthew Sager's gerber_to_gcode.

       This  manual  page  was  written  by  chrysn <chrysn@fsfe.org> for the Debian project (and may be used by
       others).

                                                   2010-11-10                                       PCB2GCODE(1)

       This manual page documents briefly the pcb2gcode command.

       pcb2gcode  is  a program that takes the files typically produced by PCB (printed circuit board) designing
       tools, in particular Gerber (RS-274X) and Excellon (an RS-274C variant) files as  parsed  by  gerbv,  and
       produces  files  that  can  be  used to control a CNC (computer numerical control) milling machine. These
       files are in G code format (RS-274D/NGC) that can be read, for example, by the linuxcnc EMC2 system.

       When these files are executed, an engraving bit is used to remove  the  surface  from  a  copper  covered
       circuit  board,  thus  creating  isolated areas. In another step, holes are drilled into the board at the
       appropriate positions, and it can be cut out in another step. (For each step, a separate output  file  is
       created.)

       pcb2gcode - command-line tool for engraving PCBs using CNCs

       These  programs  follow  the  usual  GNU  command line syntax, with long options starting with two dashes
       (`-').  A summary of options is included below.

       Instead of passing all options on the command line, nearly all options can be  stored  in  a  file  named
       millproject.  There,  options  are given one per line as option=value pairs (without the two dashes), and
       can be separated by blank lines and commented (everything after a `#` character is treated as a comment).
       Options that don't take an argument (like --metric) are entered as option=1 there.

       Unless configured otherwise, numeric values are in units of  inch  and  inch/minute.  When  the  --metric
       option is given, they are in mm and mm/minute.

       --frontfilename.gbr
              Engrave the front side according to the given file (typically used in two-sided boards).

       --backfilename.gbr
              Engrave the back side according to the given file.

       --outlinefilename.gbr
              Cut  out  the  board to the shape exposed in the given file. Typically, there is only a polygon in
              this gerber file. Alternatively, this file can contain a closed line chain (see --fill-outline).

       --drillfilename.cnc
              Convert the given file (containing drill sizes and positions) to G-code.

       For every option --x that takes a filename, there is  an  --x-output  option  that  specifies  where  the
       resulting  G-code  is saved, defaulting to x.gbr. Instead of giving each output file name, the --basename
       option can be used; the base name will be used as a prefix to the default output file names.

       The parameters that define engraving are:

       --zworkunit
              Z-coordinate at which engraving happens

       --zsafeunit
              Z-coordinate for movements between engraving steps

       --mill-feedunit/minute
              feed rate at which engraving takes place (horizontal speed)

       --mill-speedrpm
              spindle speed during engraving (rounds per minute)

       --offsetunit
              distance by which the tool movement will be outset from the contours in  the  gerber  file  to  be
              engraved

              If  this distance can't be satisfied because copper areas are too close, a warning will be printed
              and the line will be drawn between the areas. This behavior  can  be  used  to  get  voronoi-style
              (flood-filling) areas; simply set the offset to a large value (like 1 inch).

       --extra-passesnumber
              number of additional isolation passes

              For  each  extra  pass, engraving is repeated with the offset width increased by half its original
              value, creating wider isolation areas.

       The parameters that define outline cutting are:

       --cutter-diameterunit
              amount by half of which the tool path is outset from the shape in the outline file

       --zcutunit
              Z-coordinate indicating where the outline cutting ends

       --cut-feedunit/minute
              feed rate at which outline cutting takes place (horizontal speed)

       --cut-speedrpm
              spindle speed during outline cutting (rounds per minute)

       --cut-infeedunit
              maximum Z distance that is cut away in a single pass (positive value; if less then  zcut's  value,
              there will be more than one pass)

       --fill-outline
              If  --fill-outline  is  given,  it  is  assumed that the outline file contains not a polygon but a
              closed chain of lines. The board will be cut along the centres of these lines.

       --outline-widthunit
              thickness of the lines that form the outline (if --fill-outline is given)

       Drilling takes another set of options:

       --zdrillunit
              Z value down to which will be drilled

       --zchangeunit
              Z-coordinate for movements with the drill head

       --drill-feedunit/minute
              feed rate for drilling (vertical speed)

       --drill-speedrpm
              spindle speed during drilling (rounds per minute)

       --milldrill
              If --milldrill is given, the milling head will be used to drill the holes in the PCB. Holes up  to
              the  size  of  the  milling  head  will be drilled regularly (possibly creating a bigger hole than
              intended), the other holes are created by moving the head in circles using  the  feed  and  infeed
              parameters used in cutting.

       --drill-front
              use the coordinates of the front side for drilling instead of the coordinates of the back side

       These options govern the general behavior of pcb2gcode:

       --dpidpi
              resolution used internally (defaults to 1000)

       --mirror-absolute
              mirror  operations  on  the  back  side along the Y axis instead of the board center, which is the
              default

       --svgfilename
              export the resulting contours to an SVG (scalable vector graphics) file

       The only options that can't be used in the millproject file are the common ones:

       -?,--help
              Show summary of options.

       -v,--version
              Show version of program.

gerbv(1), pcb(1).

       For further information about pcb2gcode, see the project wiki ⟨http://sourceforge.net/apps/mediawiki/
       pcb2gcode/⟩.

pcb2gcode [options]