New to servos, please help/advise?

Hello group my name is David and I've lurked here for quite some time.
Thanks to all of you that post answers and ideas - you have been a
great resource for all of us newbies.

Can someone help me with a few things (power supply/encoder)?

My mill is pictured in the "Volitan" folder in the "Photos" section.
I'm guessing the table weighs around 150 lbs (I'll know for sure soon)
. I have 3 of the following servos:

---------------------------
Reliance Electric DC Brushed Servo Motors, Model E712
37.51 Oz-In/A
25.0-30.5 V/KRpm
Motor Terminal Resistance .75-1.02 Ohms @ 4A.
Maximum Terminal Voltage 60V
Maximum Continuous Speed 2100 RPM (No Load)
Maximum Peak Torque 1500 Oz-In.
Maximum Peak Current 44.5A
Maximum Continuous Stall Torque At Max Motor Temp 300 Oz-In.
Maximum Continuous Current 8.9A
---------------------------------

I have 5 TPI ballscrews, and plan on using Gecko 320's and encoders
from us Digital. Rapid rates are not a concern as it's a Hobby
machine. My thought is to use the third servo to drive the knee, and
later on get a smaller one for the quill so I can use either/or
depending on the job.

Power supply amperage? I'm confused.

3 geckos @ 20 amps max each = 60 amps. I've never seen anyone here
recommend a 60 amp supply.

3 servoes at max continuous - 26.7 amps. So I suppose it should be
somewhere in between but I'm guessing because I don't really know what
I'm talking about yet.

Power suply voltage?
This will affect RPM's and not torque, correct?


Encoder resolution. What are the pros/cons to teh different
resolutions? I'd like the ability to thread mill if that means
anything there.

Sorry this is so long, I'm not even asking all the questions I have
yet :)


Thank you!
David