From 9a3281646184063cc60d106f6815adbb77aadc87 Mon Sep 17 00:00:00 2001
From: Nettika <git@nettika.cat>
Date: Sun, 2 Feb 2025 18:03:43 -0800
Subject: [PATCH] Create band design

---
 .gitignore |   1 +
 band.scad  | 100 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 101 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 band.scad

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..974cbbb
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+*.3mf
diff --git a/band.scad b/band.scad
new file mode 100644
index 0000000..fd6340b
--- /dev/null
+++ b/band.scad
@@ -0,0 +1,100 @@
+include <BOSL2/std.scad>;
+
+$fn = $preview ? 32 : 128;
+
+band_arc_radius = 65;
+thickness = 3;
+height = 10;
+band_arc = 240;
+leg_length = 27;
+edge_radius = 0.5;
+punch_angles = [-95, -70, -45, 0, 45, 70, 95];
+tooth_width=2;
+tooth_height=2.5;
+teeth_max_angle = 110;
+teeth_spacing = 2.5;
+punch_clearance = 5;
+
+module tooth() {
+  cyl(
+    d1=tooth_width,
+    d2=edge_radius*2,
+    h=tooth_height,
+    rounding2=edge_radius,
+    anchor=BOT,
+    orient=FWD
+  );
+}
+
+module punch() {
+  region = right(
+    1,
+    p=rect(
+      [height/2+1, height/2],
+      rounding=height/4,
+      anchor=LEFT
+    )
+  );
+  linear_sweep(
+    [region, xflip(region)],
+    length=thickness+2,
+    center=true,
+    orient=BACK
+  );
+}
+
+
+module band() {
+  region = right(
+    band_arc_radius,
+    p=rect(
+      [thickness, height],
+      rounding=edge_radius
+    )
+  );
+  rotate_sweep(
+    region,
+    angle=band_arc,
+    spin=-band_arc/2+90
+  );
+}
+
+module leg() {
+  rotate(-band_arc/2+90)
+  right(band_arc_radius)
+  cuboid(
+    [thickness, leg_length, height],
+    rounding=edge_radius,
+    edges="Y",
+    anchor=BACK
+  )
+  attach(FWD)
+  xcyl(
+    thickness,
+    d=height,
+    rounding=edge_radius
+  );
+}
+
+difference() {
+  union() {
+    band();
+    leg();
+    xflip() leg();
+  }
+  for(a=punch_angles) {
+    zrot(a) back(band_arc_radius) punch();
+  }
+}
+
+for(a=[-teeth_max_angle:teeth_spacing:teeth_max_angle]) {
+  if(all([
+    for (b=punch_angles)
+    abs(b - a) > punch_clearance
+  ])) {
+    zrot(a) back(band_arc_radius-thickness/2+0.1) {
+      up(height/4) tooth();
+      down(height/4) tooth();
+    };
+  }
+}