Removing brakes from Servos

[ghurd]

I had a few (very) old servos that were pretty much un-good after I tinkered with them.
1 or 2 were useless.  Seems like 1 that had good prospects before tinkering were useless afterwards.

And yes, Abused!
I 'won' a servo on ebay... from a seller who's items were all returnable, except the servo motor I 'won'.
All the screw heads were severely messed up, anti-tamper sticker seal was broken, etc.
The coils were fine.  In fact, everything but the screw heads looked brand new.
It didn't make enough of anything to charge a AAAA nicad in a hurricane.

"Fungus" had 101% reliable numbers about his servo(s) and the loss in V/RPM and output into a battery after the , but he is out there finding himself.  Darn kids nowadays are like they were back in the '60s!  LOL

I still have a servo motor or 3 around with brakes, but was never confident about getting the things apart so they would still work afterwards.

"Have you made any W/T's built with a servo?"
In the context I expect it was intended, no.  I managed to ruin any servo motor of a suitable size I could try, by taking it apart.
BUT I do intend to try to get the brakes off at least one I have, then give it a try.  I pretty much gave up on the ones I have with brakes attached due to the failures I had.

It must have something to do with size?  (and age)  The bigger "servo" motors you guys are using must have better magnets.  The largest I ever removed the rotor from was maybe 3.3 or 4" dia class?  Maybe 5 or 7" long?
Not the monsters you guys are talking about.

This post has me ready to rip off the back of those buggers I didn't screw up yet!
G-


Just for clairity, because I know this is going to come up in searches for the next 20 years...

"Servo" motor can be taken may ways, and they can be very different.
An Ametek or Indiana is a servo motor.
A stepper motor (ie: from a junk printer) is a servo motor.
A typical muffin fan has a servo motor.
Most $$$ Kollmorgen units are servos.
A GE ECM is a servo motor, as is the F&P, LG, Ect.
A Zubbly conversion is a servo motor (not very unlike some of the early GE ECMs).
A HughP PMA is a servo motor (not unlike some Kollmorgens).
And the type you guys have is a servo motor too.

[bvan1941]

ghurd,
As usual you give lots of background as basis for logical answers! I really hope you WILL experiment with servos. I will reiterate what advice I've gotten from Mike and Adam. "Choose a servo that has the lowest rpm's, higher voltages, and suitable amperage to achieve the basic requirements for W/T parameters and load applications." ( I'm sure they didn't use those words), but It's what I took away from their discussions on this subject in Forum posts.
It appears that the servos data plate is confusing to some people when it comes to estimating current levels. I think most people are mistaking the amperage listed as the combined output from all (3) phases. Both Mike and Adam have been advising that is not the case! They've even said in some posts that that truer estimates are more like 2.5-3 times that rating. I believe them and will post both my (calculated) estimates and recorded actual results with my projects as I complete them.
 "Monster" -- Powerwise, I think I've seen some of the 1000-1500w servos advertised w/o brakes and encoders attached, are only < 15-20lbs. according to advertised shipping weights and would operate around 2k rpm's. or less. Believe both Mike and Adam have made very good W/T's Initially, in this range.

Soo go ahead and "jump in."  Would bet your observations would bring even more clarity and interest in their use!
Bill