- union(){
- translate([0,-arch_to_chord]){
- difference(){
- circle(arch_in_rad + arch_thick, $fa=0.1);
- circle(arch_in_rad, $fa=0.1);
- }
+ difference(){
+ union(){
+ ArchCircle(arch_in_rad + arch_thick);
+ for (m=[0,1])
+ mirror([m,0])
+ translate([arch_width/2,0])
+ multmatrix([[1,pbase ? -0.75 : 0,0,0],
+ [0,1,0,0],
+ [0,0,1,0],
+ [0,0,0,1]])
+ square([end_width, pbase ? pbase_tab : end_thick]);