Jobs ruined after long run

[JAZZCNC]

I thought i would post my results in the off chance it may help another new person if they have a similar issue as me with the high-z s model.
It turns out it was me, i was driving it too hard at 45mm/sec and as Jazzcnc thought the bushes were getting too hot and were binding, i have now run at both 20 and 30mm with total success, just it ran longer obviously, the model above mine the t series does not have the same bushes so i imagine the problem may not occur so easily.
Thanks to Jazzcnc and Philip at Protools who walked me through the reasoning.
One happy camper again

Bernie I don't believe the bushes getting too hot is the cause. 45mm/sec (2700mm/min) isn't overly fast and certainly won't or shouldn't be getting any bushes remotely hot unless they are wornout and knackerd.

Don't know what reasoning phillip at Proto may have tried to parm off on you but any machine at the price they charge for those things should easily be capable of cutting at 2700mm/min. If not then send it back because it's unfit for purpose.? By that I mean they sell it for cutting woods and plastics which both need cutting at those kinds of speeds and higher.!

Now provided the machine is mechanicly sound, which it should be with such low millage and that Mid band resonance isn't the cause(Which it very well could be!) Then there are only a few reasons that you would struggle to get speeds you need and none of them very good or what Philip would be keen to admit.!!

Low ballscrew pitch less than 5mm or very poor quality low effieciency lead screws.
Under sized motors or poor spec motors.
Drives running motors with Low voltage. ie 24Vdc
Drives running motors with wrong current settings.
Very poor or low frequency pulse engine.

Now I'd guess the screw pitch is at least 5mm so I'll count that out and even Low spec 5mm pitch lead screw should give 2700mm.

Next and prime suspect is Low voltage driving the motors. Steppers get there speed and to some degree torque from Voltage. So if the drives are being run on low voltage of less than 36vdc then they struggle with torque when the rpm rise. Also if the motors are wound or wired series type then torque drops away very quickly when rpm rise.
Too low voltage and motors using series wired or low spec motors with very high inductance are common cause of low performance.
So why would manufacturer use Low voltage.? Because it means they can use cheaper drives and less chance of problems because they don't run the voltage near the drives Max capabiltys.

Correct Motors using decent drives driven with good supply of Voltage 44vdc or more and connected to 5mm pitch ballscrew should easily achive 2700mm/min cutting speeds on machine this size. Even if using less efficient Acme lead screws should still be no problem.

So what I'm saying is you either have another issue like Mid band resonance, which is what I would like to hope it is. Or the Spec of the machine is very poor and IMO unfit for purpose considering they advertise it for cutting woods plastics etc which it should do at correct feeds n speeds.