Stepper Motor Controler

[Deleted]

I have a number of 4 wire (bipoler I believe) stepper motors out of old printers. I would like to be able to control the speed of rotation from about 1/4 rpm to 2 rpm. So far none of the transistor drive circuits that I have found seem to work. Most circuits use an Xor & either a JK FF or a 4013 cmos to drive the transistors. My results are very rough rotation with random direction change.
Any ideas ??
Thanks Gary for a great site & the reminder to post ;D