Simple G Scale Points Motor

thingiverse

(Sept 8, corrected silly mistake where centre sleeper did not have cut-out in base.) (This file has been revised; a new DD base has been created.) This is a basic servo driven point motor for G scale railroads. It utilizes a standard ES-08 Servo and features a simple Rack and Pinion drive mechanism. It is roughly the same size as the LGB manual points switch, and employs the same screw locations to connect to the tracks. Unlike my previous design (http://www.thingiverse.com/thing:349602), this motor is extremely compact and straightforward, but lacks the sprung points effect, which can cause trains to derail when trying to push against the points. The "Direct Drive Revised" version connects to the tracks at sleepers 1 and 3, making it more suitable for some LGB rail configurations that don't use sleeper positions 1 and 2. **Assembly Instructions** To ensure a smooth connection between the gears and the servo pinion, adjust the hex hole size in the gear using the 123D file until it provides a secure push-fit. Two slightly different sized gears are included to facilitate this adjustment. For better stability, use a standard 1.7mm x 10mm screw to fasten the gear to the servo; the shorter screws supplied with the servo may not provide enough hold. A second screw of identical size is used to keep the lid in place. When using the latest direct drive 123 model, choose from among three different pinion hex hole sizes to match your servo. In the event that water gets into the mechanism, a small drainage hole at the bottom allows you to drain it out.