back_cut_l = 4;
back_cut_w = 10; //xxx
back_prong_w = 3;
+back_hole_d = 2;
+back_hole_dia = 1 + 0.5;
module MidPlan(){
polygon([[0, 0],
translate([0,0, back_th+gap_th])
linear_extrude(height=front_th) FrontPlan();
}
+ rotate([0,0,-45])
+ translate([0, back_tot_l - back_hole_d, back_th/2])
+ rotate([0,90,0]) translate([0,0,-50])
+ cylinder(h=100, r=back_hole_dia/2, $fn=40);
}
}
}