Bowser Turntable Details

I used Bowser's indexing kit with some modifications. For the drive I used my own motor driving the wood platter provided by Bowser.

The drive motor is a large radio control airplane servo salvaged from my junk box that had the servo drive circuits removed. It is therefore just a DC motor that has a gear reduction output. On the servo output shaft is mounted a 1/32 slot car wheel with a foam tire. This slot car wheel is a drive puck that rides on the outside of the Plywood platter. The servo is pivoted on a spring loaded mount to keep tension on the drive wheel. This geared motor can move the turntable very precisely.
The motor drive supply is a simple variable DC regulated supply using a LM317 adjustable regulator. This gives better control for a prototypical movement and precise control for manual alignment if needed.

The indexing circuit board is stock but the photo resistor mount assemblies in the bridge are modified to provide better ambient light shielding with a hood and the light slot has been modified by drilling about a 1/16 in hole in it to slow the motor down as it approaches the indexing lamp.

       Click on Schematic for larger view
I used Green clear LEDs for the indexing light source. The Green spectrum is what the photo resistors are most sensitive to. I have no idea why they supplied red grain of wheat bulbs with the kit. Using the LEDs through a pin holes in the turntable wall provides an intense indexing light that can not be seen by the user.

One other gadget I added was a normally closed push button in series with the indexing pickup that if momentarily pushed will make the bridge to a 180 degree turn automatically. 

I also added ball bearings to the bridge flanged wheels and a thrust bearing from a RC helicopter in the main bridge shaft to make the bridge run as friction free as possible.

I hope this gives you some Ideas to improve the operation of your turntable

Turntable Motor Controls. The push button does a 180 degree turn

Index and Track Power Control

LM317 Regulator Turntable Speed Control Track Power and Indexing Rotary Switch business side

Green - Clear Index LEDs. The common of the LED lead is soldered to the Turntable wall and the LED is aimed through a pinhole in the wall

Drive Motor Servo made from RC servo. A Slot Car Wheel is used as a drive puck


RC Servo circuits were removed so it is just a geared motor. Bracket is spring loaded to provide tension on the drive puck