jmc 180watt servos any opinions

[the great waldo]

Hello all.
I was wondering if any forumites had any opinions on the 180watt servos jmc or whatever in cnc machine use? Woodworking and light ali work in my case. There seem to be a lot of different opinions about these motors! If anyone has good/bad experiences I would be glad for any comments.
Cheers.
Andrew

[A_Camera]

The holding torque is a weak point, but the speed is a strong point. The size is a weak point (it is very long) but the fact that it has a built in (piggy back) driver and that it has position control is a strong point. It's a compromise, because if you need a lot of holding torque and high speed you need to get a considerably larger, stronger, more expensive and more complicated servo with external drivers. I like it so far where I intend to use it, but won't change my ordinary steppers on my CNC with it. I can be wrong, but I think my steppers are doing a better job than these 180W servo motors could. Anyway, I won't find out, because buying three of these to prove my point (or not) is not worth it. While these are fairly cheap, it's cheaper to use what I have as long as it works for what I do.

[alanambrose]

Hi Andrew,

I believe Stefan G has the 'close-loop stepper' version of these on his Sorotec router (I could be wrong). As I give him 15 marks out of 10 for pretty much everything, I, for one, would be happy to emulate him. He has the 'closed-loop steppers' rather than the servos to avoid having to play around with the servo params.

He has, I think, the 3 Nm IHSS60-36-30 ones - you are looking at the 180W iHSV57-30-18-36-21-38s?

BTW I have found that JMC has a plethora of parts with similar part numbers.

Alan

[the great waldo]

Hi Alan

Thanks for that; i'll check that out. I bought one of the sorotec compact line assembly kits a couple of years ago, it's still sitting in bits in my workshop as I haven`t enough space for my original one and the new one. I'm getting all the electronic bits together for the control box and motors. I went on a a bit of a daft shopping spree buying closed loop steppers as well as the jmc servos + the original steppers (I could open an ebay shop with all the stuff) anyway I would like to see how the servos perfom as I like the fact that they seem reasonably quiet and as my workshop is not far from the kitchen any reduction in noise is going to politically be a bonus!! The part numbers from JMC have to be keenly watched as it's easy to order the wrong parts.
Cheers
Andrew