Ok thanks for that info basher, my motors are listed below.

I managed to get them really cheap £19.90 each.
Motors:
  • Motor Length: 76mm
    Shaft Dia: 6mm
    Step Angle: 1.8
    Max Rated Volts/Current/Phase: 40vdc/4.2amp/2 phase
    Holding Torque: 180N.cm - 254 ozf in
    Leads: 4