res = 50; // r1 = section radius, r2 = center-line radius module torus2(r1, r2) { rotate_extrude(convexity = 10, $fn=res) translate([r2, 0, 0]) circle(r = r1, $fn=res); } spacing=10; effrad=6; offset = sqrt( pow(2*effrad,2) - pow(spacing,2) ) / 2; translate([-spacing, -offset, 0]) torus2(1, effrad); translate([ 0, offset, 0]) torus2(1, effrad); translate([ spacing, -offset, 0]) torus2(1, effrad);