Superior Electric Steppers

[Agathon]

Very clear reply - thanks.

OK, so just to confuse myself more I've tried to fill out the Excel motor calculator here - http://www.mycncuk.com/threads/1524-...otor-do-I-need

I've attached the calculation with what I think are generous values using the Leadshine 3ph 2Nm motors LS2NmMotorCalcs.xls
This seems to look OK, but have I missed something - are my estimates as to load mass and table speed too low? The 3ph 2Nm Leadshine motors have an encouragingly flat torque curve at less than 360rpm -

If I go for conventional steppers I'll go with the AM822 drivers, but what size motor? The old steppers have a surprisingly small shaft (3/8") so Nema34s with 14mm shaft are a bit of nuisance. I see Nema23 3Nm motors with 10mm shafts - http://r.ebay.com/KuT9Ez - Are these big enough though?

Sorry for all the questions.

Just to give some idea of the sort of machine - here's a (bad) photo:

As you can see, it's a kind of mill-drill. But don't be fooled, this thing is a beast weighing in at about a tonne. The table weighs around 150kg - hence my 100kg load per axis estimate. The motors drive the ball-screws directly.