Cheers for the tips Robin, I'm still a while off finalising the plans yet and very much in the design stage still, and when I get round to picking up the design again I'll try to implement your good advice. In the meantime I have made progress in other areas. Namely I've managed to pick up 3 drivers from Wantai (DQ860MA) and built myself a power supply to power them which I'm quite proud of. Testing it out with a few Nema 17 steppers that I have for a different project all seems to work rather well. I've only been driving them back and forwards using an arduino to supply the pulses so far, but all seems good so far. I'll step up to using that old pc that I have lying around eventually but I'll need to find a hard drive for it first and install Mach 3 or similar. To be continued....