pressfit_horn v0.1

catear_headband.scad

@@ -1,6 +1,6 @@
-include <headband.scad>
+include <globals.scad>;
 
-use <headband.scad>
+use <headband.scad>;
 
 module catear(height, thickness, fractal=0, side_len=30, bend_factor=0.5, stretch_factor=1.2, debug=false, chamfer=CHAMFER, chamfer_shape=CHAMFER_SHAPE) {
   $A=[0, side_len/2];

globals.scad

@@ -0,0 +1,19 @@
+$fn=90;
+DEBUG=false;
+SIZE=60;
+HEIGHT=4.6;
+THICKNESS=3;
+PART=0.7;
+STRETCH_LEN=40;
+TIP_LEN=0.05;
+TIP_BEND=20;
+RAKE_DEPTH=1;
+RAKE_WIDTH=1;
+RAKE_STRETCH=1;
+RAKE_CHAMFER=0.5;
+CHAMFER=1;
+CHAMFER_SHAPE="cone";
+
+INSERTICLE_X = 4.6;
+INSERTICLE_Y = 7.4;
+INSERTICLE_Z = 5.4;

headband.scad

@@ -1,20 +1,5 @@
-$fn=360;
-DEBUG=false;
-SIZE=60;
-HEIGHT=4.6;
-THICKNESS=3;
-PART=0.7;
-STRETCH_LEN=40;
-TIP_LEN=0.05;
-TIP_BEND=20;
-RAKE_DEPTH=1;
-RAKE_WIDTH=1;
-RAKE_STRETCH=1;
-RAKE_CHAMFER=0.5;
-CHAMFER=1;
-CHAMFER_SHAPE="cone";
-
-use <chamfer.scad>
+include <chamfer.scad>
+include <globals.scad>
 
 module partial_ring(part, radius, thickness, height) {
   rotate(180-180*part, [0, 0, 1])

pressfit_catears.scad

@@ -0,0 +1,32 @@
+include <globals.scad>;
+
+use <catear_headband.scad>;
+use <pressfit_headband.scad>;
+use <chamfer.scad>;
+
+EAR_SCALE = 1.5;
+EAR_BEND_FACTOR = 0.15;
+EAR_STRETCH_FACTOR = 1.2;
+
+difference() {
+translate([20*pow(0.99, SIZE/2*EAR_SCALE-1-THICKNESS), 0, -THICKNESS/2])
+union() for (i=[0:SIZE/2*EAR_SCALE-1]) {
+  j=pow(0.99, i);
+  chamfer_ = floor(abs(2*i/(SIZE/2*EAR_SCALE-1)-1));
+  translate([-j*20, 0, 0])
+    rotate(90, [0, 1, 0])
+      /*chamfer(size=1, child_h=1, child_bot=-0.5, shape=CHAMFER_SHAPE)*/
+        catear(
+          debug=DEBUG,
+          height=INSERTICLE_Z*1.2,
+          thickness=THICKNESS,
+          side_len=SIZE/2*EAR_SCALE-i,
+          bend_factor=EAR_BEND_FACTOR,
+          stretch_factor=EAR_STRETCH_FACTOR,
+          chamfer=chamfer_,
+          chamfer_shape=CHAMFER_SHAPE
+        );
+}
+translate([0, 0, -THICKNESS]) cube([100, 100, THICKNESS], center=true);
+scale([1, 1, 2]) inserticle();
+}

pressfit_headband.scad

@@ -1,7 +1,9 @@
-include <headband.scad>
+include <globals.scad>
+
+use <headband.scad>
 
 module inserticle() {
-    cube([4.6, 7.4, 5.4], center=true);
+    cube([INSERTICLE_X, INSERTICLE_Y, INSERTICLE_Z], center=true);
 }
 
 module pressfit_headband(debug=DEBUG, size=SIZE, height=HEIGHT, thickness=THICKNESS, part=PART, stretch_len=STRETCH_LEN, tip_len=TIP_LEN, tip_bend=TIP_BEND) {

pressfit_horns.scad

@@ -0,0 +1,67 @@
+include <globals.scad>;
+
+use <pressfit_headband.scad>;
+
+$fn=360;
+A=30;
+N=4;
+R=45;
+LENGTH=100;
+TWIST=720;
+STEPS=360;
+SLICES=max(TWIST, STEPS, LENGTH);
+SHEIGHT=LENGTH/STEPS;
+BEND_X_FACTOR=0.5;
+BEND_Y_FACTOR=1;
+
+COLORS=[
+"#f00",
+"#f70",
+"#7f0",
+"#0f0",
+"#0f7",
+"#07f",
+"#00f",
+"#70f",
+"#f07"
+];
+
+difference() {
+  union() for (step=[1:STEPS]) {
+    a = A*(1-(step-1)/STEPS);
+    b = A*(1-step/STEPS);
+    r = TWIST/STEPS*(step-1);
+    sh_xy = 0;
+    sh_yx = 0;
+    sh_xz = 1/STEPS*step*BEND_X_FACTOR;
+    sh_yz = 1/STEPS*step*BEND_Y_FACTOR;
+    sh_zx = 0;
+    sh_zy = 0;
+    t_x = sh_xz*SHEIGHT*(step-1)*0.5;
+    t_y = sh_yz*SHEIGHT*(step-1)*0.5;
+    t_z = LENGTH/STEPS*(step-1);
+    sc_x = 1;
+    sc_y = 1;
+    sc_z = 1;
+    mm = [
+      [sc_x,  sh_xy, sh_xz, t_x],
+      [sh_yx, sc_y,  sh_yz, t_y],
+      [sh_zx, sh_zy, sc_z,  t_z],
+    ];
+    echo(a, b, b/a, r, mm);
+    multmatrix(mm)
+      color(COLORS[(step-1)%9])
+      linear_extrude(
+        SHEIGHT,
+        center=false,
+        twist=TWIST/STEPS,
+        scale=b/a,
+        slices=SLICES/STEPS
+      ) rotate(R-r)
+        circle(d=a, $fn=N);
+  }
+  translate([0, 0, INSERTICLE_Z/2])
+    inserticle();
+}
+
+echo("twist angle: ", TWIST/STEPS);