Trying to learn as much as possible about motors...specifically servos. I'm convinced that my (to be designed) router should use servos.
Figuring an aluminum gantry, with a 3.25 HP router/spindle, and a work area of about 24" by 36"...I guess I'd have to really figure out the speed and torque requirements...but maybe there are some 'general' specs we can talk about regarding DC motors:
1. What makes a DC motor worthy of being called a 'servo'? Is it just the fact that it'll spin at around 3,000RPM, it has adequate HP, and you can stick an encoder on it good enough? Or are there other specs it needs to meet (duty cycle?).
2. My "gut feel" is that for my x-axis, I'd need a hefty motor -- maybe 1/2 HP with a 1/2" or larger output shaft. Say I were to find a cheap motor like this, and it can be altered to accept an encoder, and it spins at 3,000RPM, and it likes 30 to 36VDC. Would that be something to look at, for my axis?
3. I see a lot of 12VDC motors...but I'm assuming that they just won't provide the torque needed. Usually, they seem to be for automotive applications (emissions, or blowers, etc). No good for servo adaptation, right?
4. I also see a lot of 90VDC motors, and a few 'in between' (40V to 60V). If the other specs look right (RPMS, HP), can they be used? Or, will the power supply requirements be too great?
As an example, here's a motor I was looking at tonight. I think the price is kind of high...and I suppose the rear cover would have to be removed and the shaft tapped to put a smaller shaft into it, for the encoder...but in general, would this motor "cut it" as a decent servo?
http://cgi.ebay.com/ws/eBayISAPI.dll...tem=5934321133
It's 50V...looks like it is well made...if I ever tripped across one similar for around $10-$15, would it be worth using?
Thanks!
-Chris