Model leaflet MP89 describes a scheme for building a Tricky Track, a useful and popular model at exhibitions. Tricky Track is a set of mechanisms linked into a continuous track upon which everything is powered by the weight and/or movement of the train - no other power sources are permitted. The leaflet describes a standard which would allow a club, for example, to build a huge track with each member building one or more components.
The photographs below illustrate some extension mechanisms I have put together recently. Hopefully building them or similar components is reasonably obvious from the pictures. The train has a 120 rpm Mike Rhoades motor. This Tricky Track could be seen in action at Thornbury Model Engineering Exhibition 2015.