From 818c75d6c4651c0a50e2e203c81f97547be2d801 Mon Sep 17 00:00:00 2001
From: Luke Hubmayer-Werner <mongoose41@gmail.com>
Date: Mon, 23 Dec 2024 14:47:47 +1030
Subject: [PATCH] first headpiece attempt

---
 CFTubes.scad | 100 ++++++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 80 insertions(+), 20 deletions(-)

diff --git a/CFTubes.scad b/CFTubes.scad
index 4e76adb..262eec8 100644
--- a/CFTubes.scad
+++ b/CFTubes.scad
@@ -15,19 +15,21 @@ fret_inlays = [[3, "真"], [5, "尊"], [7, "正"], [9, "清"], [12, "評判"], [
 
 
 module neck(string_spacing=18, string_margin=4.5, num_strings=3, target_neck_thickness=15, scallop_depth=3, num_frets=24, fret_width=2.4) {
-	neck_length = fret_scale_length(0)+fret_width/2;
+	fw2 = fret_width/2;
+	neck_length = fret_scale_length(0)+fw2;
 	neck_width = (num_strings-1)*string_spacing + string_margin*2;
-	// Could do some trig to work out exactly how much to add for the scallop depth, but we're subtracting anyway
-	angle_excess = 20;
 	module neck_stock() {
+		angle_excess = asin((scallop_depth+fw2)/target_neck_thickness);
+		a0 = 90-angle_excess;
+		a1 = 270+angle_excess;
 		rotate([-90, 0, 0])
 			linear_extrude(neck_length)
-			polygon([for (a = [90-angle_excess:1:270+angle_excess]) [neck_width*0.5*sin(a), -target_neck_thickness*cos(a)]]);
+			polygon([for (i = [0:300]) let(a=lerp(a0, a1, i/300.0)) [neck_width*0.5*sin(a), -target_neck_thickness*cos(a)]]);
 	}
 	module scallops() {
 		for (fret = [0:num_frets]) {
-			x0 = fret_scale_length(fret-1) - fret_width/2;
-			x1 = fret_scale_length(fret) + fret_width/2;
+			x0 = fret_scale_length(fret-1) - fw2;
+			x1 = fret_scale_length(fret) + fw2;
 			xmid = lerp(x0, x1, 0.5);
 			// Radius it?
 			arc = arc_points([[x0, scallop_depth], [x1, scallop_depth], [xmid, 0]]);
@@ -101,21 +103,25 @@ module cf_tube(x1, x2, tolerance = 0.3) {
 	}
 }
 
-module cf_square(x1, x2, tolerance = 0.2) {
+module cf_square(x1, x2, tolerance = 0.2, taper_x1 = true, taper_x2 = true) {
 	x = CF_Square_Width+tolerance;
 	translate([-x/2, x2, -x/2])
 	cube([x, x1-x2, x]);
-	hull() {
-		translate([0, x2, 0])
-			cube([x*1.2, 0.2, x*1.2], center=true);
-		translate([0, x2+5, 0])
-			cube([x, 0.2, x], center=true);
+	if (taper_x1) {
+		hull() {
+			translate([0, x1, 0])
+				cube([x*1.2, 0.2, x*1.2], center=true);
+			translate([0, x1-5, 0])
+				cube([x, 0.2, x], center=true);
+		}
 	}
-	hull() {
-		translate([0, x1, 0])
-			cube([x*1.2, 0.2, x*1.2], center=true);
-		translate([0, x1-5, 0])
-			cube([x, 0.2, x], center=true);
+	if (taper_x2){
+		hull() {
+			translate([0, x2, 0])
+				cube([x*1.2, 0.2, x*1.2], center=true);
+			translate([0, x2+5, 0])
+				cube([x, 0.2, x], center=true);
+		}
 	}
 }
 
@@ -143,8 +149,62 @@ module fret_tube(from_fret, to_fret, fret_width=2.4) {
 	}
 }
 
+module headpiece(string_spacing=18, string_margin=4.5, num_strings=3, target_neck_thickness=15, scallop_depth=3, fret_width=2.4) {
+	headpiece_length = 36;
+	cf_square_length = 32;
+	fw2 = fret_width/2;
+	x0 = fret_scale_length(0)+fw2;
+	neck_width = (num_strings-1)*string_spacing + string_margin*2;
+	bend_radius = 24;
+
+	module stock() {
+		angle_excess = asin(scallop_depth/target_neck_thickness);
+		a0 = 90-angle_excess;
+		a1 = 270+angle_excess;
+		translate([0, x0, 0])
+			rotate([-90, 0, 0])
+				linear_extrude(headpiece_length)
+				polygon([for (i = [0:300]) let(a=lerp(a0, a1, i/300.0)) [neck_width*0.5*sin(a), -target_neck_thickness*cos(a)]]);
+	}
+	module string_tubes() {
+		string_thicknesses = [4.9, 4.2, 3.0];
+		module string_tube(diameter, fn=36) {
+			hole_r = diameter/2;
+			bend_r = bend_radius + hole_r;
+			union() {
+				for (a = [0:89]) {
+					hull() {
+						translate([0, bend_r*sin(a), bend_r*cos(a)]) sphere(hole_r, $fn=fn);
+						translate([0, bend_r*sin(a+1), bend_r*cos(a+1)]) sphere(hole_r, $fn=fn);
+					}
+				}
+				hull() {
+					translate([0, bend_r*sin(90), bend_r*cos(90)]) sphere(hole_r, $fn=fn);
+					translate([0, bend_r*sin(90), -target_neck_thickness]) sphere(hole_r, $fn=fn);
+				}
+			}
+		};
+		for (i = [0:num_strings-1]) {
+			string_diameter = string_thicknesses[i];
+			x = -neck_width/2 + string_margin + (i*string_spacing);
+			translate([x, x0+2, -target_neck_thickness+scallop_depth+fw2]) string_tube(string_diameter);
+		}
+	}
+	difference() {
+		stock();
+		string_tubes();
+		for (i = [-1:2:1])
+			translate([i*7.5, 0, -7])
+				cf_square(x0+cf_square_length, x0, taper_x1=false);
+		// αβγδεζ
+		translate([0, x0+headpiece_length, -5]) rotate([90, 0, 180]) linear_extrude(0.3, center=true)  text(text = "01β.α", font = "Deja Vu Sans", halign = "center", valign = "center", size = 4);
+	}
+}
+
 echo(fret_scale_length(0) - fret_scale_length(8));  // 225.724
 echo(fret_scale_length(8) - fret_scale_length(24));  // 240.335
-//fret_tube(0, 8);
-//translate([30, 0, 0])
-fret_tube(8, 24);
+// fret_tube(0, 8);
+// //translate([30, 0, 0])
+// fret_tube(8, 24);
+
+headpiece();