+// -*- C -*-
+
+include <utils.scad>
+
+hex_across = 12.70 - 0.3;
+screw_dia = 8.0 + 0.0;
+
+min_th = 0.425;
+extra_th = 0.5;
+
+// calculated
+
+total_th = min_th + extra_th;
+hex_rad = hex_across / 2 / cos(30);
+
+module Plan(){
+ difference(){
+ circle(r = hex_rad, $fn = 6);
+ circle(r = screw_dia/2);
+ }
+}
+
+module Elevation(){
+ square([ hex_across*2, min_th*2 ], center=true);
+ hull(){
+ rectfromto([ 0, -1],
+ [ 0.1, min_th]);
+ translate([ hex_rad, 0 ])
+ rectfromto([ 0, -1 ],
+ [ 1, total_th]);
+ }
+}
+
+module Blivet(){
+ intersection(){
+ linextr(0, total_th + 1)
+ Plan();
+ linextr_y_xz(-hex_across, hex_across)
+ Elevation();
+ }
+}
+
+Blivet();