FreeCAD scripts for PCB CAD/CAM & FEM

fcad_pcb is yet another way to improve ECAD/MCAD collaboration between FreeCAD and KiCAD.

The original purpose of these tools was to do PCB milling in FreeCAD. It can do much more now.:

• It can generate gcode from kicad_pcb directly without going through the gerber stage.
• It can let your modify the PCB directly inside FC (done already),
• and potentially export back to kicad_pcb (partially done).
• and finally it can generate solid tracks, pads and plated drills to enable FEM and thermal analysis on KiCad pcb boards.

Installation

The fcad_pcb macro is written in Python and requires FreeCAD 0.17 or later to work properly.

1. Clone this repo into your freecad macro directory. To check what the default path of your macro directory is go to dropdown Macro > Macros.. and find the path in the field User macros location

   cd <path/to/your/macros/directory>
   git clone https://github.com/realthunder/fcad_pcb/

2. Enter the locally cloned repository

   cd fcad_pcb/

3. Download the repository submodules

   git submodule update --init --recursive

4. Restart FreeCAD

Usage

At this time fcad is usable through the FreeCAD python console.

• Start FreeCAD,
• Launch the python console Enable through the View > Panels > Python Console dropdown menu
• Invoke the python import command to load fcad_pcb:

  from fcad_pcb import kicad

Result: you are now ready to use fcad_pcb.

Generating copper layers

from fcad_pcb import kicad
pcb = kicad.KicadFcad(<full_path_to_your_kicad_pcb_file>)
pcb.makeCoppers()

Note: the file path syntax should be one of the following:

pcb = kicad.KicadFcad('C:/Users/fooDesktop/MyProject/MyPCBfilekicad_pcb')

Alternatively if you don't want to replace backslashes for a Windows system:

pcb = kicad.KicadFcad(r'C:\Users\foo\Desktop\MyProject\MyPCBfile.kicad_pcb')`

Generating copper layers / pads / drills + ready for FEM workbench

Generate these full solid objects ready to for the FEM workbench

from fcad_pcb import kicad
pcb = kicad.KicadFcad(<full_path_to_your_kicad_pcb_file>)
pcb.make(copper_thickness=0.035, board_thickness=1.53, combo=False, fuseCoppers=True )
#
# NOTE: KiCAD 5.99 and later added possibility to specify per layer thickness including
#       dielectric layers. You are no longer required to explicitly supply thickness
#       parameters in any of the function calls as shown above.

Supply copper thickness per layer, pass a dictionary instead.

Use either integer or layer name

• integer (0~31, 0 being the front and 31 the back)

• layer name for key. Note: key None can be used for default thickness.

  pcb.make(copper_thickness={None:0.05, 0:0.04, 'B.Cu':0.09},
           board_thickness=1.53, combo=False, fuseCoppers=True)
  #
  # NOTE: KiCAD 5.99 and later added possibility to specify per layer thickness
  #       including dielectric layers. You are no longer required to explicitly
  #       supply thickness parameters in any of the function calls as shown above.

Generating a single copper layer

pcb.setLayer('F.Cu')
pcb.makeCopper()

Filtering by net name

For local nets you have to specify full hierarchical name

pcb.setNetFilter('GND')
pcb.makeCopper()

pcb.setNetFilter('GND','VCC')
pcb.makeCopper()

Shape without intermediate document objects

In case you only want the shape without any intermediate document objects

from fcad_pcb import kicad
pcb = kicad.KicadFcad(<full_path_to_your_kicad_pcb_file>, add_feature=False)

# Or, you can set the parameter later
pcb.add_feature = False

# All the above makeXXX() calls now returns a shape without creating any features
# For example, if you want the complete fused copper layers.
# Note: 'thickness' can be a dictionary for per layer thickness
coppers = pcb.makeCoppers(shape_type='solid', holes=True, fuse=True)
Part.show(coppers)

Note: that there is a sample board to play with inside this repo: test.kicad_pcb

Screenshots

FEM of tracks and drills

Full PCB in FreeCAD

PCB for milling

FEM of tracks and drills

Requirements

FreeCAD >= v0.17