hotwire an AC servo

[Karl_T]

We're parting out a monster matsuura bed mill. I think the model is M1000DC.

The Z is at top of travel. We've got nearly all usable parts off the machine but can't get the Z axis to turn. You have to lower the Z to get at the coupling box to disconnect the servo.

I know you can hot wire a DC brushed servo just by hooking it to a bettery charger. Can anything similar be done on this servo? next choice is a pipe wrench on the ball screw which will surely ruin it.

Karl

[Al_The_Man]

What is stopping the Z from back feeding when off?
It can be anything from a Pin engaging, servo brake, Counter Balance Hydraulic lock, If hydraulic lock, you would have to take the valve off.
A large mill especially, usually has counter-balance of some kind.
Al.

[Karl_T]

We can't find any sort of hydraulic lock. Took a whole bunch of stuff off. maybe we should look some more. the machine is at tool change height. Is there a lock pin, possibly???

The head has a large counter weight on a chain.

We can only get at the old resolver and turn there, twisted that off. You can't get the cover off the coupling box till you lower the head. There a spring steel covering the screw, we're thinking of torching that tommorrow, but this might ruin that ball screw.

The other two axis turned hard for 1/2 turn and then went nice, this one is being a stone *****. There is significant surface rust on the exposed parts of this mill.

We have a second mill like this one, and really want the spare parts.

Karl

[Al_The_Man]

If you have the service manuals for the machine it should tell you if you have any lock of any kind.
I have driven a AC servo motor in synchronism on the bench with another by direct connection of the 3 phase leads from first to second motor, but I suspect this may not work if the second motor is under any sort of high load.
Is there no way to access a plain part of the ball screw in order to turn it with a padded pipe wrench?
Al.

[Karl_T]

No service manuals, could REALLY use a set especially to get the other machine running.

The machine is really stripped, we confirmed there is no clamping device of any kind on the Z ball screw.

The ball screw sits in a trough type pocket that only leaves a bit over 1/4" clearance from the metal spring cover. maybe 1/2" if we rip the metal spring out somehow. How hard is a ball screw? may we could drill holes 1/4" by 1/4" deep and make a custom spanner wrench. A few drill hole at the very end of travel shouldn't hurt anything.

We decided to call it a week and think on it. We're weekend warriors on this job.

Here's an eBay listing of the machine we're trying to get going
http://cgi.ebay.com/MATSUURA-Model-M...3A1%7C294%3A50

We also got a very similar machine at the same auction we're trying to part out.

Karl

[Al_The_Man]

It is most likely a precision ground BS so it is going to be case hardened, probably not drillable.
At least the control manuals you can down load off the MEAU site, it appears to be an M50 controller.
Al.