# Clausing 8530 Mill X Axis Power Feed



## calstar (Nov 27, 2016)

This unit was dead from the day I got mill, any ideas of what goes wrong with them? They have a reputation for not being the most reliable power feeds, that and the fact this one is 60 yrs old. I opened it up hoping I'd see a loose wire(no such luck), I guess the first thing to do is check the on/off /on switch.


This is a view of the motor, I don't think this is burned, just 60yrs of oily dust, what do you think?



and another view, potentiometer with motor below it






thanks, Brian


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## Terrywerm (Nov 27, 2016)

Carefully remove the brushes if you haven't already done so. Blow it out real well and then reinstall the brushes. See if it works. If the brushes are getting short, you might want to take measurements off of the old ones and see if you can source some new ones so that the originals can be replaced.


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## Bob Korves (Nov 27, 2016)

Follow the wires and see where you have continuity and where you do not.  Narrow it down until you have found the problem(s).


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## calstar (Nov 27, 2016)

Hey Terry, brushes are fine, al least 1/2 remaining, next is continuity(when I locate my multimeter).  Brian


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## Terrywerm (Nov 27, 2016)

It was worth a look though, right?


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## O-brian (Nov 28, 2016)

In the photos the potentiometer (variable transformer) looks like a burned spot on the winding near the bottom edge.  Check this winding and also the contact on the wiper.  The wiper is the output to the motor.  You could bypass the potentiometer and see if the motor works.  This will help track down the problem.
Have a great day
Dennis


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## hman (Dec 1, 2016)

You definitely need an ohm meter.

A couple years ago I bought a used mill with a non-working power feed.  The inside of the housing was kinda covered with black soot.  Checked the motor by connecting an ohm meter across the brushes.  Good windings were an ohm or two, but many of them showed zero ohms.  Field windings were OK (several ohms).  In your case, also check the Powerstat, as per O-brian.  Note that this is a variable transformer, not just a potentiometer.  The control contact is an adjustable "center tap" on the transformer.

If the windings on the Powerstat are burned through on the contact surface (as they appear to be on the photo), you might be able to peel the ends of the wires out of their potting material and solder them together on the back side of the donut.  It will leave a bit of a "blank" spot at that point on the contact face, but 99% of the adjustment range will remain useable.


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## calstar (Dec 2, 2016)

Thanks for the input guys, I don't really understand some of it but I'll try to muddle through as best as I can. This project is not on the top of my priority list but at least I have some direction.

Brian


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