+ polygon([[-0.1, y_T_r * r0],
+ [x_T_r * r0, y_T_r * r0],
+ [x_B_r * r1, y_B_r * r1],
+ [x_B_r * r1 + wall_x_r * rnom + plus, y_B_r * r1],
+ [basew + plus, top],
+ [-0.1, top]]);
+ translate([0, -d_OC_r * r0])
+ circle(r = r0);
+ }
+}
+
+module CrossSection(plus=0) {
+ for (m=[0,1]) {
+ mirror([m,0])
+ CrossSectionHalf(plus);
+ }
+}
+
+module CrossSectionDemo(){ ////toplevel
+ color("black") CrossSection(2);
+ CrossSection();
+ for (rc=[["red", r1],
+ ["blue",r0]]) {
+ color(rc[0]) translate([0, -d_OC_r * rc[1]]) circle(r = rc[1]);
+ }
+}
+
+strap_width = 4 + 0.5;
+total_len = 70;
+
+strap_count = 2;
+
+strap_wall_h = 1.5;
+strap_wall_l = 2.0;
+
+writing_dx = total_len / 3;
+writing_dy = basew*2;
+
+module HalfClamp(){ ////toplevel
+ difference(){
+ rotate([90,0,0])rotate([0,90,0]){
+ linear_extrude(height=total_len)
+ CrossSection();
+
+ for (i=[0 : strap_count]){
+ if (i*2 != strap_count) {
+ translate([0, 0,
+ total_len * (i + 0.5) / (strap_count + 1)])
+ for (m=[0,1]){
+ mirror([0,0,m])
+ translate([0,0, strap_width/2])
+ linear_extrude(height=strap_wall_l)
+ CrossSection(strap_wall_h);
+ }
+ }
+ }
+ }
+
+ translate([0, -basew, top])
+ Commitid_BestCount([writing_dx, writing_dy]);