Hi,
I'm about to strart a conversion of a emvio 25 CNC mill (G0704 size) and a bit confused on steppers .
I've read lots of info on steppers and there has been a lot of development of the technology in recent years which has led to some confusion. What i've been pondering on using are a nema 23 3Nm, 3 phase hybrid closed loop steeper (with encoder) with suitable controller. I was intending on direct drive and not use pulleys. Would i need a bigger than 4Nm on the Z as i'm intending on putting a bigger motor and doing a power drawbar or would a gas strut/counter weight be enough.
I can't seem to find any suppliers of 3 phase steppers in the UK of the size i'm looking for unless my googling skills have let me down
looking at the tormach white papers on why they use steppers and advantages/disadvantages of 2/3 phase and analogue/digital drivers over servo's has left me a bit confused on what would make a nice reliable conversion that doesn't lose steps and becomes a pain which i think only happens if i'm over driving if i understand it correctly.
I did look at the teknic hybrid steppers but postage and import taxes makes them quite expensive are there options i'm missing? or am i doing the normal thing and over thinking and 2 phase hybrid stepper from cnc4you or somewhere would make a nice conversion and should just on with it and stop googling further. I don't think the size of the machine really justifies servo's unless someone doesn't agree?

Regards
Rob