Hi,

I have a General 25-100 10" swing midi lathe and its about 2 years old.
I have just become aware that at about 3000 rpm and above the headstock
bearings make an intermittent but sill rather coninuous popping chirp (
but not very high pitched ) racing sound. I have run the motor with out
the belt and it is quiet, so its not the motor. When you rotate the
headstock spindle by hand you can somewhat hear the bearings make noise
but it is neither a rough or high pitched sound. It just sounds like
the bearings are dry or something ( they are permanetly sealed bearings
). As I have more recently been using the lathe at higher speeds I do
not know it this is an old or new problem. There doesnt seem to be any
play in the spindle.
Any suggestions if the bearings need to be replaced?

In article .com,
wrote:

When you rotate the
headstock spindle by hand you can somewhat hear the bearings make noise
but it is neither a rough or high pitched sound.

There doesnt seem to be any play in the spindle.


A: bearings always need to be replaced.

B: but not until they are causing a noticeable problem.

What gets damaged if, say, the bearings are a touch on the dry side? The
bearings, and nothing else. So when they are adequately damaged as to be
a problem, you'll replace them, and all damage (potentially) caused by
not replacing them today will be fixed.

Meanwhile, if, say the noise is not from dried out or damaged bearings
(unlikely at 2 years, especially if it's a General, not a General
International), but is, say, simply the seals making some noise, as
sometimes happens, or belt noise, it may be many years before anything
occurs that causes the bearings to actually become damaged, and then
you'll replace them.

So, until there is noticeable roughness or play in your spindle, I don't
see any need to replace the bearings. It's not like a car that's going
to strand you beside the road if you fail to catch a wheel bearing in
time. If you feel better with a set of spare bearings on hand, get some
spare bearings, but do try to label them well and store them on the
machine somewhere, so that your kids won't toss them out as useless
random junk as they are parting out your shop after you've gone on to
your reward (many years hence, hopefully)...

--
Cats, coffee, chocolate...vices to live by

wrote: (clip) I have run the motor with out the belt
and it is quiet, so its not the motor. (clip)
^^^^^^^^^^^^^^^
I can think of a way it could still be the motor (I'm not saying it is).
The belt could be putting enough load on the bearing to make it squawk.
Taking the belt off would silence it. Harbor Freight has their mechanic's
stethoscope on sale right now. That's a really good way to isolate noises.

We have one of those generals at the turners club and a couple of the
members also have them.
They, the 10" General International, does have a tendency to have the
pulleys come loose.
So make sure all the set screws are tight.

Now if you are certain that the headstock bearings are the culprit,
don't wait to chance them, there's a good chance the bearing will
cease, and if that happens there's a chance the inner or outer bearing
race is pulled around, and if that happens it will damage the lathe.

Small chance, maybe, but why take it, you really have a problem if it
happens, and you will have to change them anyway in short order.

Try to get better quality sealed bearings from your bearing supply
place, they should not be that expensive.

Have fun and take care
Leo Van Der Loo


wrote:
Hi,

I have a General 25-100 10" swing midi lathe and its about 2 years old.
I have just become aware that at about 3000 rpm and above the headstock
bearings make an intermittent but sill rather coninuous popping chirp (
but not very high pitched ) racing sound. I have run the motor with out
the belt and it is quiet, so its not the motor. When you rotate the
headstock spindle by hand you can somewhat hear the bearings make noise
but it is neither a rough or high pitched sound. It just sounds like
the bearings are dry or something ( they are permanetly sealed bearings
). As I have more recently been using the lathe at higher speeds I do
not know it this is an old or new problem. There doesnt seem to be any
play in the spindle.
Any suggestions if the bearings need to be replaced?

wrote in message
oups.com...
I have just become aware that at about 3000 rpm and above the headstock
bearings make an intermittent but sill rather coninuous popping chirp (
but not very high pitched ) racing sound. I have run the motor with out
the belt and it is quiet, so its not the motor. When you rotate the
headstock spindle by hand you can somewhat hear the bearings make noise
but it is neither a rough or high pitched sound. It just sounds like
the bearings are dry or something ( they are permanetly sealed bearings
). As I have more recently been using the lathe at higher speeds I do
not know it this is an old or new problem. There doesnt seem to be any
play in the spindle.
Any suggestions if the bearings need to be replaced?


Suggest the higher grade bearings. When you call your bearing place they'll
probably offer options within the same dimensions. Take the sealed higher
quality. You're purchasing one set, so the couple extra bucks won't mean
much, not like the manufacturer, who sees it as two less profit. Chirps
sound like binding, since loose or worn bearings rumble. Run it up, let it
chirp a while, turn off and touch the bearing gingerly. If it's warm,
replace.

wrote:
Hi,

the headstock
bearings make an intermittent but sill rather coninuous popping chirp (
but not very high pitched )


just a thought - you said the headstock is making the noise but could
it be the tail centre bearings?