This is a linear slide actuator project that can be used for positioning or making a small machine or for robotics. It can be made longer or shorter by lengthening/shortening the guide rods and lead screw. It uses a standard widely available DC gearmotor which operates from 4.5 to 6 volts. The main components are all 3D printed. It is easy to assemble and durable. A photo-interrupter sensor and encoder wheel is included to track the axis position.