I agree, avoid stepper systems, they're yesterday's newspaper. Servos
avoid all the resonance headaches and have faster travels than a stepper
system of equal power. The saving grace of steppers is they're cheap,
but you know the old saying -- Good, fast, cheap, pick any two.

Eric R Snow wrote:

On Sat, 29 Jan 2005 08:30:44 -0500, "Lucky Strike"
wrote:


Is anybody out there using Anaheim Automation's "DPJ72LC" LC Series on their
knee mills?


From what I've seen the product looks fairly capable and cost effective.

I'd appreciate any comments.


I looked at the above mentioned product. It is a stepper system. I
would avoid making a machine with steppers. Gecko Drives makes servo
drivers that use step and direction signals on the input side. For an
80 volt 15 amp driver you would spend $114.00. Of course, you will
need three drives. US Digital sells inexpensive encoders that will
work with the Gecko drives. And there are several step and direction
software packages available. Some for free and others, like MAXNC, for
a pretty good price. I have bought and used the MAXNC software that I
used to drive a small stepper driven X Y stage. The software worked
well and was easy to setup. But I had problems with the stepper motors
losing steps. To avoid losing steps the stage could not move faster
than 30 inches per minute. Gecko has an engineer who will gladly help
you decide what size motor to get, either servo or stepper. Just my 2
cents worth.
Cheers,
Eric R Snow,
E T Precision Machine