commit 6f62c24f9b1cbf0f356959a4cdeb85b0bc2724d9
Author: Adam Goldsmith <adam@adamgoldsmith.name>
Date:   Tue Mar 1 12:18:18 2022 -0500

    Initial Commit

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..a951e72
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+*.stl
+/__pycache__/
+/*.svg
diff --git a/key_bittings.py b/key_bittings.py
new file mode 100644
index 0000000..f8b8373
--- /dev/null
+++ b/key_bittings.py
@@ -0,0 +1,31 @@
+MM_PER_IN = 25.4
+
+
+# A progression of root depths, decreasing by a constant amount each step.
+def linear_depths(start, end, base, increment):
+    return {str(depth): base - (depth - start) * increment
+            for depth in range(start, end + 1)}
+
+
+def depths_in_to_mm(depths):
+    return {name: depth * MM_PER_IN for name, depth in depths.items()}
+
+
+# https://www.lockreference.com/wp-content/uploads/2019/03/Yale-Disc-Tumbler.pdf
+yale_disc = depths_in_to_mm({
+    "1": .250,
+    "2": .230,
+    "X": .220,  # also called "7"
+    "3": .210,
+    "4": .190,
+    "5": .170,
+})
+
+# https://www.lockreference.com/wp-content/uploads/2018/01/Yale-.019.pdf
+yale_019 = depths_in_to_mm(linear_depths(0, 9, .320, .019))
+
+# https://www.lockreference.com/wp-content/uploads/2018/01/Yale-.025.pdf
+yale_025 = depths_in_to_mm(linear_depths(0, 7, .320, .025))
+
+# https://www.lockreference.com/wp-content/uploads/2018/09/National-Disc-Tumbler-Single-Sided.pdf
+national_disc_tumbler = depths_in_to_mm(linear_depths(1, 4, .250, .025))
diff --git a/snap_on_templates.py b/snap_on_templates.py
new file mode 100644
index 0000000..1450558
--- /dev/null
+++ b/snap_on_templates.py
@@ -0,0 +1,88 @@
+import cadquery as cq
+from cadquery import exporters
+
+import key_bittings
+
+MM_PER_IN = 25.4
+
+key_thickness = 2 + .2
+
+text_size = 4
+text_depth = 0.5
+text_margin = 2
+
+lishi_width = 18 - 0.3
+lishi_depth = 5
+lishi_height = 9.98
+lishi_overhang_height = 2.25
+lishi_overhang_width = 1
+lishi_overhang_radius = 1 - .000000001  # workaround to fillet a part with the same thickness
+corner_radius = 0.5
+side_thickness = 1
+bottom_thickness = 2
+back_thickness = 1.5
+# this number is somewhat estimated, but quite important
+# it is the offset from the end of the pliers to the point of the cutter
+lishi_cutter_offset = .54 * MM_PER_IN
+key_guide_width = 15
+key_guide_height = 12.5
+
+notch_width = 1
+notch_height = 1.32
+notch_depth = 0.5
+
+
+def lishi_template(name, depth):
+    result = (
+        cq
+        .Workplane("front")
+        .box(lishi_width + side_thickness * 2, lishi_depth + lishi_overhang_width, lishi_height + bottom_thickness)
+        .tag("lishi_interface")
+        .edges("not >Y").fillet(corner_radius)
+    )
+
+    # TODO: positioning could be better
+    result = (
+        result
+        .faces("<Y").workplane().move(0, bottom_thickness/2)
+        .rect(lishi_width, lishi_height).cutBlind(-lishi_depth)
+    )
+
+    result = (
+        result
+        .faces("<X", tag="lishi_interface").vertices(">Y and >Z")
+        .workplane(offset=-side_thickness, centerOption="CenterOfMass")
+        .rect(lishi_overhang_width, lishi_overhang_height, centered=False).extrude(-lishi_width)
+        .edges(">Z").edges("<Y").fillet(lishi_overhang_radius)
+    )
+
+    result = (
+        result
+        .faces(">Y", tag="lishi_interface").vertices(">X and <Z")
+        .workplane(centerOption="CenterOfMass")
+        .rect(key_guide_width, key_guide_height, centered=False).extrude(key_thickness + back_thickness, combine=False)
+        .tag("key_guide")
+        .edges("not <Y").fillet(corner_radius)
+        .faces(">X", tag="key_guide").vertices("<Z and <Y").workplane(centerOption="CenterOfMass").center(0, bottom_thickness + lishi_cutter_offset - depth)
+        # ideally, the key profile would be passed in as an argument
+        .rect(key_thickness, depth, centered=False).cutThruAll()
+        .union(result)  # this seems like a fairly bad way to do this, but it does work
+    )
+
+    result = (
+        result
+        .add(result.objects[0].Edges())
+        .faces(">Y", tag="key_guide").vertices(">XZ").workplane(centerOption="CenterOfMass")
+        # TODO: better positioning
+        .moveTo(lishi_width / 2 + side_thickness, -notch_height/2)
+        .rect(notch_width, notch_height).cutBlind(-notch_depth)
+        .faces(">Y").workplane(centerOption="CenterOfMass").text(name, text_size, -text_depth)
+    )
+
+    return result
+
+
+for name, depth in key_bittings.national_disc_tumbler.items():
+    #log(f"{name}, {depth}")
+    result = lishi_template(name, depth)
+    exporters.export(result, f'national_disc_tumbler_{name}.stl')