Hello, I have seen a machine that can round bread dough very easily and dont undestand how the movement is achieved. As you can see, there are 2 drums that turn at the same time, one outer, one inner. The inner drum's movement is what I cant figure out. In my opinion it turns at the same rate and direction as the outer drum, but not only does that, also there is another movement, a "circular" movement around the longest axis, that moves the dough pieces around the edges of the outer drum. Watch these videos please: http://youtu.be/fFjovsZokcc http://youtu.be/6gicSTS-nCo?t=13m35s http://youtu.be/2VF_ipbpgAM?t=4m42s This last video is very interesting because you can see how the drum in still position goes in and out in a circular movement, combine that with the rotation and its like using the hand to make a dough ball. My question how that circular movement of the inner drum is produced?