September 14, 2015

Hello World, How to Mill Printed Circuit Boards (PCB)

Hello World, How to Mill Printed Circuit Boards (PCB)
This post is part of the Hello World Projects.

There are many ways to create custom PCBs (printed circuit boards). I like milling because the CNC mill can etch the traces, drill the through-holes, and cut the board all with one machine. All in a few minutes if your board is small.

My friendly neighborhood SoDo MakerSpace has a Shapeoko 2, which I've been using. In this tutorial, I'll show you how mill some PCBs.

Credit for the original version of this tutorial goes to ähöüokul on Instructables, and thanks to Alex Cheker for pointing me to it. Now, on with the show!


Step 1: Export to SVG

In Fritzing:
  • Export SVG: Export PCB > Etchable SVG

Step 2: Process SVG with InkScape

  • Open InkScape (download )
    filename either xx_etch_copper_top.svg or xx_etch_copepr_bottom.svg
  • [Optional] View > Outline
  • Edit > Select All (Ctrl+A)
  • Object > Ungroup (Ctrl+Shift+G), repeat until you see "No groups to ungroup" in the bottom
  • Path > Stroke to Path
  • Path > Union
  • File > Save As > *.svg
  • Step 3: Open SVG with MakerCam


    Some Navigation Tips
    • To Pan: Toolbar > Hand Icon
    • To Zoom: Toolbar > Plus/Minus Icon or Scroll Up/Down
    • To Select: Toolbar > Arrow Icon, then click or click+drag to select

    Step 3: Make Copper Trace

    • Select copper trace outlines
    • Create Profile CAM > Profile
    Profile for Traces> 12 mil< 12 mil
    tool diameter (in)0.010.008
    target depth (in)-0.008-0.006
    inside/outsideOutside
    safety height (in)0.5
    stock surface (in)0
    step down (in)0.0040.003
    feedrate (in/min)6
    plunge rate (in/min)10
    directioncounter clockwise
    Tool: Engraving Bit (20 deg, 0.2mm)

    Step 4: Make Through Hole

    • Select through hole outlines
    • Create Profile: CAM > Drill Operation
    Through Hole Profile:
    tool diameter (in)0.035433
    target depth (in)-0.075
    drill locationpath center
    hole spacing (in)0.5
    safety height (in)0.5
    stock surface (in)0
    peck distance (in)0.05
    plunge rate (in/min)5
    Tool: Drill Bit (0.9mm)

    Step 5: Make Board Outline

    • Select board outlines
    • Create Profile: CAM > Profile Operation
    Board Outline Cut Profile:
    tool diameter (in)0.0625
    target depth (in)-0.075
    inside/outsideOutside
    safety height (in)0.5
    stock surface (in)0
    step down (in)0.015
    feed rate (in/minute)6
    plunge rate (in/minute)10
    directionCounter Clockwise
    Tool: Square Endmill (1/16 in)

    Step 6: Calculate GCode

    • Cam > Calculate All

    Step 7: Add Tabs

    • Select Board Outline Path
    • Add Tabs: CAM > Add Tab to Selected
    Tab Settings
    tab spacing (in)1
    tab width (in)0.15
    tab height (in)0.25

    Step 8: Export GCode

    • Cam > Export GCode
    • Select one path at a time
    • Click "Export Selected Toolpath"

    Tools to use during CNC
    tracesengraving bit (20 deg, 0.2mm)
    holesdrill bit (0.9 mm)
    boardsquare endmill (1/16 in)

    Check Your Code

    Bloop bloop!

    Cut it OUT!

    Step 9: Mill It!

    • Clamp board in
    • Turn Shapeoko On
    • Unlock GRBL Controller
    • Click Choose File button
    • Bring Engraving Bit to touch the surface of the board
    • Click the "Start" button

    Repeat for through holes (w/ drill bit), then the board cut (w/ endmill)

    Step 10: Snap the Tabs

    Snap and you're set!

    I've managed to get some super fine boards with this method. Check out this Intel Edison breakout board I did .

    It's so pretty!

    Got it? Got it. Now go make things.

    Related Tutorials: