pi_screw_hole_dia = 2.3;
pi_screw_hole_wall = 2.3;
-module PiMount(pi_mount_z=5){
+pi_sz_z_incl_ribbon = 18.0;
+
+pi_mount_z_min = 1.75;
+pi_mount_z_def = 2.50;
+
+// calculated, output
+
+function pi_ribbon_top_z(pi_mount_z= pi_mount_z_def)
+ = pi_mount_z + pi_sz_z_incl_ribbon;
+
+module PiMount(pi_mount_z= pi_mount_z_def){
sxy = pi_nom_sz/2 - [1,1] * pi_nom_centres_in;
for (mx=[0,1]) mirror([mx,0,0]) for (my=[0,1]) mirror([0,my,0]) {
difference(){