lengthL=100; widthL=10; lengthT=lengthL-widthL; pinD=3; $fn=30; //linkage parts module linkageWhole(){ hull(){ circle(d=widthL); translate([lengthT,0]) circle(d=widthL); } } module holes2(){ circle(d=pinD); translate([lengthT, 0]) circle(d=pinD); } //actual linkage module linkage(){ difference(){ linkageWhole(); holes2(); } } linkage();