Part of a turntable mechanism built for Trevor Marshall's previous On2 layout. The pivot is a 1/4" mono phone plug and jack combination. A brass bushing was made to accept the cable end of the phone plug, and a nylon gear was bored out to fit the outside diameter of the plug body. A brass plate to support the superstructure (built separately) was affixed to the top of the bushing. Power fed to the tip and ring contacts on the phone jack allows for the audio output of sound equipped locos to remain uninterrupted throughout the turntable rotation. The wires are run from the plug solder tabs up to the rails inside the bushing body. Trevor built the styrene and wood superstructure, I dealt with the machining.
The turntable is powered by a Switchmaster stall motor mounted on a spring loaded swing arm. The spring keeps the stall motor pinion gear in mesh with the bridge's pivot gear. The entire bridge can be removed from the top of the layout for maintenance or detailing by simply pulling teh assembly upwards. A Lenz automatic reversing relay deals with the polarity change relative to the lead tracks during rotation.
