# 935 mill centrifugal switch



## PeterT (Apr 18, 2020)

Again! I've been happily milling away for several months back & the dreaded cogging sound started again yesterday when the on switch is pressed. If you have never experienced this, count yourself lucky. But if you haven't, it resembles a loud mechanical noise like a gear case with some loose extra bolts. 

So by now I know the drill. Shimmy up the ladder, remove the motor grill, examine the plastic fan to see if it had migrated down to interfere with the centrifugal switch. Last time I thought I mounted it flush to the motor shaft just as visual reference. Now it was maybe a smidge lower but not much. I've loctited the bolt to keep it secure but its basically pressure clamping the plastic boss hub which isn't the most robust looking part. So I removed the fan, I can see that the CS has not migrated up because I can see my witness scribe line on the shaft from before. With fan completely removed, flip the switch, motor starts & purrs like a kitten.

So now my theory is this is just a problematic fan design. The underside is kind of a dome shape so its obviously quite close to potentially interfering with the CS counterweight action. This time I turned a nylon spacer disc, 0.75" ID x 1.0" OD x 0.30" thickness. It's a little fat but I'm going to try it this way. Now the fan sits a little above the end of the motor shaft but still lots of ceiling room to the motor grill plate. I set the disc on the CS hub. Now if the drifts down it will come too rest on the spacer & hopefully not interfere. Well about 100 starts since its been installed, fingers crossed and no sacrificial incense to the capacitor gods.


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## YYCHM (Apr 18, 2020)

What make and model mill is this?

Craig


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## John Conroy (Apr 18, 2020)

Here's hoping that's a permanent fix


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## PeterT (Apr 18, 2020)

Craig, its a model 935 VS, mini Bridgeport style, Taiwan made, sold by Modern Tool (and others).
John, yes!


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