Double Helix Tower LEGO GBC Module

This LEGO Great Ball Contraption (GBC) module uses Nicolas’ (Nico71) ball pump to push the balls up through the tower. The balls then roll down a rotating double helix that is made from LEGO slides (6 x 12 x 8 studs, 11267). It works very reliably and does not jam. There are some more photos over at Flickr.