feat: completed the new approach of generating PCBs from the master

README.md

@@ -27,10 +27,9 @@ more (easily accessible) thumb keys. There are so many candidates
   - minimise overall footprint by using internal standoffs (thanks for the idea
       [ErgoTravel](https://github.com/jpconstantineau/ErgoTravel))
   - use only 1U key caps to minimise size and because stabilisers are annoying
-  - One PCB design that works as all 3 layers of a sandwich design: base, PCB and
-    switch plate. Idea taken from
-    [for-split-keyboard](https://github.com/peej/for-split-keyboard) and
-    [mitosis](https://www.reddit.com/r/MechanicalKeyboards/comments/66588f/wireless_split_qmk_mitosis/)
+  - author a single "master" PCB and use a python script to generate the 3
+      layers of the sandwich case. Makes life much easier to keep them all in
+      sync.
   - support 5-pin/PCB mount switches
 
 ## Gerbers
@@ -71,6 +70,36 @@ manufactured. The listed quantity is to assemble *both halves*.
 Note1: we need to construct our own M2 standoffs of the right length as they
 don't stock M2x9 female-female standoffs.
 
+
+# Generating 3 layers of sandwich case
+We edit a single PCB file that contains the information required to generate all
+3 layer (switch plate, circuitry, base) of a sandwich case keyboard. Keeping it
+all in one file ensures that things like mounting hole always stay lined up.
+
+There is some magic in the settings of items on the PCB to indicate what layer
+they belong on. Read the code for the specifics but as a general guide:
+  - we use Eco1.User as the templates for edge cuts that only appear on some
+      layers
+  - the width of the drawing lines are slightly different so we can determine
+      which belongs on each layer
+  - the thickness of text is slightly different so we can determine which
+      belongs on each layer
+
+You *must* have Kicad installed in your system. Doing this makes the `pcbnew`
+python module available. Make sure you don't have any virtualenv, etc activated
+as you need to be using you system-wide python. Check for the module with:
+
+```python
+import pcbnew
+```
+
+Now you can regenerate the PCBs with:
+
+```bash
+python ./generate_pcbs.py
+```
+
+
 # Generating gerbers
 Using KiCad 5.1.4, here's the settings to generate gerbers.
 
@@ -125,6 +154,17 @@ Sort of. You won't be able to use OLED screens and there's no solder jumpers so
 you'll have to jump some wires between the OLED header SDA/SCL pins and the
 SLAVE_LED pin/data pin on the unused TRRS jack.
 
+**What happened to a single PCB that works as all 3 layers?**
+Originally I tried to make one PCB design that works as all 3 layers of a
+sandwich design: base, PCB and switch plate. The idea was taken from
+[for-split-keyboard](https://github.com/peej/for-split-keyboard) and
+[mitosis](https://www.reddit.com/r/MechanicalKeyboards/comments/66588f/wireless_split_qmk_mitosis/).
+I failed because I wanted to have minimal post-manufacture cutting by hand and
+JLCPCB kept rejecting my desgins as they didn't have strong enough supports to
+hold the PCB together though the whole manufacture process. So now we have
+"master" PCB design and use a python script to generate the PCBs for each layer
+from that master.
+
 **Do you have keyboard-layout-editor source?**\
 Yes. Either [this file](./layout.kle) in this repo or here's a (hopefully up to date)
 <a href="http://www.keyboard-layout-editor.com/##@@_x:3&t=#000000%0A%0A#115219;&=E%0A%0A#&_x:9.75&t=#000000%0A%0A#115219%0A#9914a6;&=I%0A%0A*%0A%7D;&@_y:-0.875&x:2&t=#000000%0A%0A#115219;&=W%0A%0A/@&_x:1;&=R%0A%0A$&_x:7.75&t=#000000%0A%0A#115219%0A#9914a6;&=U%0A%0A/&%0A%7B&_x:1&t=#000000%0A%0A#115219;&=O%0A%0A';&@_y:-0.875&x:5;&=T%0A%0A%25&_x:5.75;&=Y%0A%0A%5E;&@_y:-0.625&x:1;&=Q%0A%0A!&_x:13.75;&=P%0A%0A%22;&@_y:-0.625&x:3;&=D%0A%0A3&_x:9.75&t=#000000%0A%0A#115219%0A#9914a6;&=K%0A%0A8%0A);&@_y:-0.875&x:2&t=#000000%0A%0A#115219;&=S%0A%0A2&_x:1;&=F%0A%0A4&_x:7.75&t=#000000%0A%0A#115219%0A#9914a6;&=J%0A%0A7%0A(&_x:1&t=#000000%0A%0A#115219;&=L%0A%0A9;&@_y:-0.875&x:5;&=G%0A%0A5&_x:5.75;&=H%0A%0A6;&@_y:-0.625&x:1;&=A%0A%0A1&_x:13.75;&=/:%0A/;%0A0;&@_y:-0.625&x:3&t=#000000%0A#0b458a%0A#115219;&=C%0A%0A+&_x:9.75&t=#000000%0A%0A#115219%0A#9914a6;&=%3C%0A,%0A%0A%5D;&@_y:-0.875&x:2&t=#000000%0A#0b458a%0A#115219;&=X%0A%0A-&_x:1;&=V%0A%0A/=&_x:7.75&t=#000000%0A%0A#115219%0A#9914a6;&=M%0A%0A~%0A%5B&_x:1&t=#000000;&=%3E%0A.;&@_y:-0.875&x:5&t=#000000%0A%0A#115219;&=B%0A%0A%60&_x:5.75;&=N%0A%0A/:;&@_y:-0.625&x:1&t=#000000%0A#0b458a%0A#115219;&=Z%0A%0A/_&_x:13.75&t=#000000;&=?%0A//;&@_y:-0.625&x:3;&=Del&_x:9.75&t=#000000%0A%0A%0A#9914a6;&=%0A%0A%0A%3E%0A%0A%0A%0A%0A%0A%E2%86%93;&@_y:-0.875&x:2&t=#000000;&=Alt&_x:1;&=GUI%0AEnter&_x:7.75&t=#000000%0A%0A%0A#9914a6;&=%0A%0A%0A%3C%0A%0A%0A%0A%0A%0A%E2%86%90&_x:1&t=#000000&a:7;&=%E2%86%91;&@_y:-0.875&x:5&a:4;&=Shift&=Ctrl&_x:3.75&t=#115219;&=Numb%0AEnter&_t=#000000;&=Space;&@_y:-0.625&x:1;&=Leader&_x:13.75&a:7;&=%E2%86%92;&@_y:-0.375&x:2;&=&_a:4;&=Swap&_t=#000000%0A#0b458a;&=Esc&_t=#ab0202;&=Media&_t=#9914a6;&=Brkt&_x:3.75&t=#000000;&=Tab&=AltTab&=Bspc&=Swap&_a:7;&=">permalink</a>

generate_pcbs.py

@@ -1,4 +1,9 @@
 #!/usr/bin/env python
+# Reads the PCB "master", that we edit by hand, and generates 3 output PCBs for
+# each of the layers of the sandwich style case. This helps to keep everything
+# in sync between the layers. You must have Kicad installed on your system as
+# that installs the `pcbnew` module that we use. AFAIK you can't install pcbnew
+# via pip.
 import sys
 import os
 import pcbnew
@@ -12,6 +17,7 @@
 
 ALL_LAYERS_WIDTH = 50000
 NOT_TOP_PLATE_WIDTH = 50010
+ALL_LAYERS_TEXT_THICKNESS = 150100
 
 
 def refill_zones(board):
@@ -21,10 +27,24 @@ def refill_zones(board):
     filler.Fill(zones)
 
 
+def is_logo(module):
+    return module.GetReference() == 'CHICKEN'
+
+
+def is_brace(module):
+    return module.GetReference().startswith('Brace')
+
+
+def is_brace_not_for_top(module):
+    return module.GetReference().startswith('BraceNotTop')
+
+
 def delete_electronics(board):
     for module in board.GetModules():
-        # FIXME don't delete chicken
-        # FIXME don't delete mount holes
+        ref = module.GetReference()
+        is_mounting_hole = ref.startswith('Mount')
+        if is_mounting_hole or is_logo(module) or is_brace(module):
+            continue
         board.Delete(module)
 
 
@@ -37,18 +57,22 @@ def generate_base_pcb():
     board = pcbnew.LoadBoard(master_pcb)
     print('Creating base PCB: %s' % base_pcb)
     delete_electronics(board)
+    for module in board.GetModules():
+        if is_brace(module):
+            if is_brace_not_for_top(module):
+                continue
+            board.Delete(module)
     delete_tracks(board)
     for d in board.GetDrawings():
-        # FIXME don't delete name, version, licence
+        if type(d) is pcbnew.TEXTE_PCB:
+            if d.GetThickness() == ALL_LAYERS_TEXT_THICKNESS:
+                continue
         if d.GetLayerName() == 'Edge.Cuts':
             if type(d) is pcbnew.DRAWSEGMENT:
                 if d.GetWidth() == NOT_TOP_PLATE_WIDTH or d.GetWidth(
                 ) == ALL_LAYERS_WIDTH:
                     continue
         board.Delete(d)
-    # FIXME delete template ProMicro edge.cuts
-    # FIXME delete template choc edge.cuts
-    # FIXME delete template switch edge.cuts
     refill_zones(board)
     board.Save(base_pcb)
 
@@ -57,17 +81,17 @@ def generate_middle_pcb():
     board = pcbnew.LoadBoard(master_pcb)
     print('Creating middle PCB: %s' % middle_pcb)
     for d in board.GetDrawings():
-        # FIXME don't delete name, version, licence
-        if d.GetLayerName() == 'Edge.Cuts':
+        if type(d) is pcbnew.TEXTE_PCB:
+            continue
+        layer_name = d.GetLayerName()
+        if layer_name == 'F.SilkS' or layer_name == 'B.SilkS':
+            continue
+        if layer_name == 'Edge.Cuts':
             if type(d) is pcbnew.DRAWSEGMENT:
                 if d.GetWidth() == NOT_TOP_PLATE_WIDTH or d.GetWidth(
                 ) == ALL_LAYERS_WIDTH:
                     continue
         board.Delete(d)
-    # FIXME delete template ProMicro edge.cuts
-    # FIXME delete template choc edge.cuts
-    # FIXME delete template switch edge.cuts
-    # FIXME remove reset switch cut
     refill_zones(board)
     board.Save(middle_pcb)
 
@@ -77,9 +101,21 @@ def generate_top_pcb():
     edge_cuts_layer_id = board.GetLayerID('Edge.Cuts')
     print('Creating top PCB: %s' % top_pcb)
     delete_electronics(board)
+    for module in board.GetModules():
+        is_brace_for_top = not is_brace_not_for_top(module)
+        if is_brace(module) and is_brace_for_top:
+            continue
+        ref = module.GetReference()
+        is_mount_for_top = ref.startswith(
+            'Mount') and not ref.startswith('MountNotTop')
+        if is_mount_for_top:
+            continue
+        board.Delete(module)
     delete_tracks(board)
     for d in board.GetDrawings():
-        # FIXME don't delete name, version, licence
+        if type(d) is pcbnew.TEXTE_PCB:
+            if d.GetThickness() == ALL_LAYERS_TEXT_THICKNESS:
+                continue
         if d.GetLayerName() == 'Edge.Cuts':
             if type(d) is pcbnew.DRAWSEGMENT:
                 if d.GetWidth() == ALL_LAYERS_WIDTH:

generated_pcb/.gitignore

@@ -1,2 +1,3 @@
 *.pro
 fp-info-cache
+*-bak