How to make a fast linear actuator from a gear motor and an old disk drive

To control various units in toy cars, a linear actuator (drive, actuator) is required. For example, to control the bucket arm on an excavator, you need some kind of hydraulic cylinder operating on low voltage.

You can make such a linear drive, which is also very fast and nimble, from an old computer two and a half inch drive. There is a worm gear with a wide thread pitch.

Will need

Brass tube 4 mm - http://alii.pub/62lt1j
Geared motor N20 - http://alii.pub/62lt2i

Making a drive from a gear motor and an old disk drive

We remove the stepper motor with the worm gear from the drive.

We take out the worm itself and, if necessary, if a large overhang is not needed, we cut it off.

Next, we cut the brass tube to the size of the worm with a margin. At one end we make a side hole 0.6 mm in diameter.

We press the tube onto the gear motor shaft. This is very easy to do, since one goes very well with the other.

Insert a pin into the side hole. This can be any contact from a radio component.

It must fit into the groove of the worm. The connection is then fixed by soldering.

Subsequently, it is cut with pliers and sanded to a smooth surface.

The actuator is ready. It would be a good idea to lubricate it with thick lubricant before use.

Through the gearbox, rotation is transmitted to the tube, which rotates. The worm is fixed motionless. During rotation, the wedge moves along the groove of the worm, resulting in a translational force and the rod extends. If you change the polarity of the motor, the rod will go backwards.