November 21, 2025
Description
This is a compact,fully 3D-printed linear actuator designed for modularity and easy integration into automation projects.
It uses an SG90 360° continuous-rotation servo together with a rack and pinion drive and two micro switches for automatic stroke limiting.
The default version provides ~60 mm of travel, but the stroke can be easily changed by modifying the length of the groove on the gear rack.
To make this easier i included 40 mm, 50 mm, and 60 mm rack versions in the STL folder. Custom stroke lengths can be made by modifying the STEP file of the gear rack.
This actuator is designed to be simple to assemble, easy to wire, and reliable enough for general motion applications.
I also included detailed step by step assembly instructions with pictures, plus Arduino example code to get the actuator running.
Bill of Materials (BOM)
1. SG90 continuous-rotation servo (360° version)
2. 6× M3×20 screws
3. 6× M3 nuts
4. 6× M3×10 screws
5. 2× 10T85 micro-switches with roller lever
6. 0.25 mm² solid-core wire
License:
BY-NC-SA