difference(){
union(){
import("./LCD_Knob.STL");
translate([0,7.5,0])cylinder(r=5, h=12, $fn=50);
}
translate([0,7.5,-0.01])cylinder(r=3.1, h=5.3, $fn=50);
translate([-5,7.5-1,-0.01])cube([5,2,5]);