Quote Originally Posted by Buba b View Post
Well i didnt get away with the tax so thats another £43 to add to the £189 for the Gecko , so if id checked around and wanted the hassel of conecting drivers and break out board up , the price wouldnt have been much differant than buying the gear from Zap in the first place. As Gary says i dont think the performace will suffer as im going to use 48v 7.3 amp power supply , its just that youv,e paid for the motor holding torque and would like to use the full spec of the motors. Its for a mini mill so i think it will make enough speed for what i want ..... time will tell .
well you haven't really, you will never get close to seeing the holding torque in practice whatever driver you have. Where the Gecko scores over any other driver is the clever stuff Mariss has built into them, resonance damping, step morphing, etc.

Remember that below the motors corner speed the torque is essentially flat except for resonances (which is where the gecko scores over other drivers which can show marked troughs in the torque at low revs). Above the corner speed the torque is inversely proportional to speed less the detent torque. A bigger motor will have a higher detent torque. the corner speed is related to inductance and drive volts and is independent of drive current. Once above the corner speed a smaller motor at higher voltage can produce more torque than a bigger motor driven at the same voltage as the bigger motor will often have higher inductances - this is despite the fact the bigger motor might have a higher holding torque.