Ruled surface Oloid knot

An oloid is a 3D object formed by the hull of a two linked congruent circles placed in perpendicular planes, so that the center of each circle lies on the other circle.

With those two circles, if you generate the inner ruled surface, you get a nice knot...
Based upon "the Wallace Line" blog (http://kitwallace.tumblr.com/post/85762927079/ruled-mobius-strip) here is an adapted openscad script allowing to easily print the two halves of the oloid knot


see http://youtu.be/EWawYvZxRKE