translate(v = [0, -material_width, 0]){
rotate(a = -90, v = [0, 1, 0]) {
cube( [1.75 * mm_per_inch + material_width,
1.5 * mm_per_inch + 2 * material_width,
translate(v = [0, -material_width, 0]){
rotate(a = -90, v = [0, 1, 0]) {
cube( [1.75 * mm_per_inch + material_width,
1.5 * mm_per_inch + 2 * material_width,