Hello everybody. This is my first post here, I say hello to all forum.

I think about CNC router, portal XZY. For metal cutting. It will heavy enough, so I plain to use x2 stepper motor for each axis.

I've looked in youtube and google, and completely misunderstand how I have to connect controller driver PSU & motor.

On this video I see just motor & controller & PSU connected to controller.
Rockcliff CNC Stepper Motor Driver - YouTube

But motor so small.

In this forum I've read

stepper motor needs to be powered by at least 20 times the rated voltage. That would be 70V, so 48V would seem to be your best PSU Voltage
I am looking to something like this

KL34H280-55-4A (1/2" Single Shaft) Specification Price: $89
640 oz In. Hybrid Motor
1.8° /200 Steps Per Rev.
4.5A Amps Current Per Phase ( Bipolar Parallel)
4-wire Bi-polar, NEMA 34 Frame
What does it means 4.5A Amps Current Per Phase? I have to multiply all phases to get really current consumption?

I have used this calculator
Stepper Motors
with 40% of holding torque because it move.

256 oz*in x 400 rpm = 75watt

If I'll get
KL-600-48 48V/12.5A $129.95
115V /230V

It has 48*12.5=600watt

I need 75*6=450watt

But if I want to get more power motor, may I use this scheme?

http://s017.radikal.ru/i410/1111/2e/c084f6a19f19.jpg

My machine has heavy Y axis with spindle of 4kw about 75 kg (200 lb), two stepper motor have up and down it by Z axis. Of course Z axis used rarely than X or Y.
X axis carries desk made from steel, ~ 120 lb.
Generally I can Use x2 gear or belt system to increase Z load ability.

Thank you forehead.