cpp7 = cppB + [1,-1] * catch_knob_dia/2
+ [ catch_stem_beside_gap, -catch_stem_below_gap ]
+ [ 0, -catch_pin_height ]
+ [-1,1] * catch_cr;
cpp11 = cpp7 + [1,0] * catch_cr;
cpp7 = cppB + [1,-1] * catch_knob_dia/2
+ [ catch_stem_beside_gap, -catch_stem_below_gap ]
+ [ 0, -catch_pin_height ]
+ [-1,1] * catch_cr;
cpp11 = cpp7 + [1,0] * catch_cr;