This is the design for the drive unit that will move the wagons on the travers in the "Kassefabrikk". It measures about 25mm cube. Split frame pickup.The brown parts are 3D printed by Shapeways in steel for the weight. The pinkred plates are plastic also printed by Shapeways. The green also plastic by Shapeway. This makes a 3 point compensation for optimal contact and adhesion. To complete is N scale wheels, Exactoscale wormgears and a 6mm gearmotor from Mikroantriebe. To further make it reliable I plan to use a decoder from CT electronic (Tran) and stay alive puffer from Fishermodel.