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Hi James
I agree with Bojan's comments and perhaps I can add the following comments as not so long ago I adapted an older type hard drive stepper motor to drive a simple mount through a gearbox.
Firstly, you have to obtain or make up a stepper motor driver which is basically a circuit driven by an oscillator to provide through other interface electronics the correct drive to the stepper motor to obtain the required motion and speed.
As well as Bojan's comments there is another thing to look out for. Stepper motors come with four wire (the most common) or five wire connections to the driver coils. You must make sure you get the right driver circuit for the stepper motor you have recovered.
I obtained my stepper motor driver kit from Oatley Electronics in Sydney
(Google them). Since mine was a 5 wire motor I got their kit number
K142D, but I see from their on-line catalogue that they also have a kit
K142B for four wire stepper motors. (See Complete Kit List page 3).
Cost of each of these units is about $27 plus postage which is good value. I also see that they have kits to allow control from a PC.
Having made the driver kit you then have to decide how to connect it to the four or five wires. This can be a bit of a puzzle but with a multimeter
to separate the two groups of windings and a bit of patience in systematically trying out connection combinations you can then find the one that drives the stepper motor correctly. You will also find straps/connections that allow you to stop/start and reverse the direction of travel. Also you may will find a strap that allows you to select the internal oscillator or connect to an external drive source. With the internal
oscillator the speed of the stepper motor will depend on using the inbuilt components or changing say the capacitor in the oscillator circuit to run the motor at different speeds. Note that if you try to run a stepper motor too fast it will stall due to a lag in current build up in the stepper motor coils at high clocking rates. Also small stepper motors have very low torque so you may need an external gearbox to adapt (eg in my case to the 10min cycle of the worm on my mount).
So, although the above kits are easy to make up a bit of electronics expertise and fiddling will be required to match the stepper motor to your desired application.
Whoa---this explanation turned out longer than I anticipated but it may be helpful to you and perhaps others who may wish to embark on this little adventure!
Cheers Peter
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