Design Example: Ring Turntable

This example demonstrates actuating an aluminum ring lazy-susan bearing using a stepper motor with friction roller drive.

200 mm Version

The turntable comprises a commercial ring bearing and a support structure laser-cut from 6 mm plywood. The outer diameter of the bearing is 200mm, and the OD of the drive roller is typically 15.47mm, for an approximate ratio of 12.93 motor revolutions per ring rotation. With a 200-step NEMA17 stepper motor, a full rotation is about 2590 counts.

The SolidWorks model files and individual DXF cutting files may be found in the FlatPackExamples/Ring-Turntable folder, or may be downloaded as a single file as Ring-Turntable.zip.

The specific bearing tested is a VXB Kit12879, although the form factor is available from multiple sources.

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A stepper-motor powered turntable built around a commercial lazy-susan bearing. The motor has a friction-drive roller pressed directly against the outer ring of the bearing. The inner ring is supported by the plywood structure. The roller is tensioned with a spring below the pivoting support.

392 mm Version

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The larger version is designed for CNC fabrication, milled from 9mm plywood. It is drawn as an alternate configuration in the same SolidWorks files. It features a lazy-Susan bearing with a 392mm outer diameter and uses a NEMA17 stepper motor with planetary reduction gear.

The specific bearing tested is a VXB Kit11281, although the form factor is available from multiple sources.