Yet another update to my first marble machine and this time much faster than the last one. The new design works really well so the only improvement I could think to make was to put a motor on it, saving many ours of tedious winding. The machine runs from a pair of AAA batteries and can be wound even with the motor attached should your batteries run flat. It's the same kit with or without a motor so if you take the motor off afterwards you end up with a normal kit.
This kit is available for purchase through my shop http://msraynsford.myshopify.com/products/marble-machine-1