I'm hearing worrying noises from the spindle of my Millrite model MVI vertical mil. I have the manual, which has some drawings, but it isn't clear to me how one gets the spindle apart and back together. For one thing, the various drawings I have don't really fit together to match what I see on the mill. I know people have replaced these bearings without too much trouble, but some guidance from the survivors would be appreciated before I try.
Thanks,
Joe Gwinn
Are you sure it is the main spindle bearings, or could it be some smaller bearing somewhere in the head? Some machines have additional bearings even on the spindle to prevent the top extension from whipping. but those are very inexpensive commodity bearings.
Jon
I am sure of nothing except that if I take the belt off and let the motor run, no funny noises. Hmm. I last did that when a prior new noise happened a few months ago. I should repeat the test. I've been busy at work, and had not been using the Millrite all that much.
Anyway, I think it's time to take the spindle apart, if only to clean and regrease it. For all I know, it has never been taken apart since it was made in
1965.Joe Gwinn
If it is similar to a Bridgeport, there is a backgear assembly, and a direct drive clutch. If so, you can disengage all the clutches and gears and see what makes noise when you spin it. When I got my Bridgeport 1J head, all the bearings in it were massively shot except the main spindle bearings. It didn't make bad noises when I ran it, but I was glad I opened it up and took a look. Some of the smaller bearings had crumbled the ball spacers and thrown off their shields. Would have caused a HUGE disaster in no time if I hadn't dug into it.
Jon
The Millrite has no such components. The quill and spindle are simple direct drive from a V-belt.
I have been getting advice on the Burke Mills group (Yahoo), and will probably disassemble the quill and spindle next weekend.
Joe Gwinn
And if the Millrite has a variable speed pulley set, you start getting noise when the Delrin bushings inside the movable pulley half (on both the spindle and the motor shaft) get worn. Especially so if the Delrin jacket on the key follower in the shafts.
A quick google Search turns up a lot of hits on the MVI relative to spindle bearings -- and I consider it unlikely that there would be that many with bad/failing bearings.
However -- I seem to have come across a suggestion that it is fixed speed belt, in which case this does not apply.
Good Luck, DoN.
This will be checked.
It is fixed speed, with a stepped cone pulley, all driven from a VFD. No Reeves Drive.
Joe Gwinn
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