Newbie (ageing rapidly!)

[ManicMetal]

You're right 2.5mm pitch screws.
I've already had the X and Y drives running (from a signal gen) up to about 60kHz (2800mm/min on 16 ustep) Where the power supplies run out of voltage to drive the 2.8mH inductance. I loaded the bed with my heaviest vice, and angle plate.

It isn't a matter of resolution 8 ustep would give me 1.5um resolution (way more than the tolerances of the machine) but 16 ustep does give a noticeably smoother motion than 8. There is hardly any reduction in torque (this is more a factor of adequate drive voltage). I've specified 2000mm/min at 16 ustep to stay within reasonable rpm for the motors while keeping to a frequency the motion controller should be capable of, I can always reduce this if needed (commissioning trials will prove the limits and determine the maximum ramp rates).

I'll take a look at the Acorn system, seems a shame to abandon Mach3 and Mill Wizard, I like their simplicity.

[JAZZCNC]

I've already had the X and Y drives running (from a signal gen) up to about 60kHz (2800mm/min on 16 ustep) Where the power supplies run out of voltage to drive the 2.8mH inductance. I loaded the bed with my heaviest vice, and angle plate.

It isn't a matter of resolution 8 ustep would give me 1.5um resolution (way more than the tolerances of the machine) but 16 ustep does give a noticeably smoother motion than 8.

Time will tell on this because things change when chips start flying and resonance's start taking affect. Also are you 100% sure the motion is smoother or is it just the change in motor sound that makes you think this.?

I'll take a look at the Acorn system, seems a shame to abandon Mach3 and Mill Wizard, I like their simplicity.

Doesn't get any easier than Acorns software and the built in Conversational Cam more than matches Mill wizzard. Another thing I can tell you with 100% certainty is that the motion is much smoother than Mach3. The motion planner is much more advanced and with the Smoothing feature enabled motion is noticably better.

Only USB device I've had any success with is UC300 and even then didn't fully trust it due to odd unexplained happening on several machines. Gave it benefits of doubt thou because the machines that did occur on used the same Dell Pc's which I've had issues with regards USB.
To be honest the PC is the biggest issue for USB and even when optimised in windows still get issues. Mostly I think quality of PC plays big part.

With Ethernet never get any issues of any kind and I've got dozens of customer machines that use them. Some of them in some pretty noisy environments, ie: next to plasma machines. Try that with USB and your doomed.!

My point being here I'm trying to help pass on my experience and not to slag off USB. If you or others choose to ignore this advice then that's fine by me, it's your money you waste it any way you like.

The Frequency/Ms setting etc is irrelevant really because so many variables come into play and each motor/drive/controller/machine combo will be affected slightly differently. But my experience is that high Ms just stress's the controller for virtually no gains. What you gain in one area you loose another and to some degree depends on how your using the machine.! . . .Low down you'll see the smoother action but up high the motors/drives feel the pain and become open to resonances.

However It's just flick of few switches to change so no Big deal provided you've got the frequency to start with and Most External controllers will have more than enough any way so again no Big deal.