I recently set up a used KO Lee S714 surface grinder and was a little
disappointed at the finish, though my experience on these tools leaves a lot
to be desired. The surface almost seems to have very shallow scallops at
regular intervals. They can't be felt by hand and a fingernail doesn't catch
anywhere. There is a bit of noise as the grinder winds up but that seems to
be coming mostly from the motor. The grinder appears to be in otherwise
very good condition.

I checked the spindle runout with a gage head and amplifier and am seeing
about 0.00075" with the gage tip on the tapered spindle nose (wheel & collet
were puulled off and belts between spindle and motor were removed). I can
also get about 0.0015" deflection in the spindle by manually pushing or
pulling the spindle toward or away from the gage tip. The spindle feels
reasonably cool after running for 45 minutes without a wheel or collet
mounted.

This seems to be pretty far out of spec to me, but opinions would be
appreciated from those that know better than I.

If this does need attention, is there any chance that the bearings just need
adjustment? There's a circular disk threaded into the outboard side of the
spindle with holes for a pin spanner wrench. I haven't mucked with that yet
but presume that it's there to adjust bearing pre-load.

If the bearings need to be replaced what are the chances of being able to do
this myslef? A manual for a slightly different KO Lee grinder suggests that
spindles must be returned to the factory for rebuilding.

TIA, Mike

In article ,
Mike Henry wrote:
I recently set up a used KO Lee S714 surface grinder and was a little
disappointed at the finish, though my experience on these tools leaves a lot
to be desired. The surface almost seems to have very shallow scallops at
regular intervals. They can't be felt by hand and a fingernail doesn't catch
anywhere. There is a bit of noise as the grinder winds up but that seems to
be coming mostly from the motor. The grinder appears to be in otherwise
very good condition.

Hmm ... before we get into the matter of play, I have a some
questions to ask:

1) It the motor original?

2) If not, did you replace a three-phase motor with a single-phase
motor?

3) If it still has the original three-phase motor -- how are you
running it?

a) From genuine power company supplied three phase?

b) From a VFD?

c) From a rotary phase converter?

d) From a static phase converter?

If your answer is either (2) or (3-d), that could be a source of
your surface finish problem.

I checked the spindle runout with a gage head and amplifier and am seeing
about 0.00075" with the gage tip on the tapered spindle nose (wheel & collet
were puulled off and belts between spindle and motor were removed).

With the spindle warmed up, or after it has been sitting cold
for a while?

I can
also get about 0.0015" deflection in the spindle by manually pushing or
pulling the spindle toward or away from the gage tip.

Is that in the spindle bearings, or in the ways of the vertical
slide? (To tell -- shift the gauge to measure the spindle housing and
repeat the test.

I think that your measurements may be a bit high -- but the
runout (if it is *consistent* runout, and not slop in the bearings)
would probably be tuned out when you true your wheel with a diamond.
(You *did* true it first, didn't you?)

The spindle feels
reasonably cool after running for 45 minutes without a wheel or collet
mounted.

Then it at least is probably not too tight --but it might be too
loose.

This seems to be pretty far out of spec to me, but opinions would be
appreciated from those that know better than I.

Another thing to check is whether the pitch of the scallop
matches the teeth of the rack gear on the bottom of the table. If so,
then there is proably some slop in the table ways.

If this does need attention, is there any chance that the bearings just need
adjustment? There's a circular disk threaded into the outboard side of the
spindle with holes for a pin spanner wrench. I haven't mucked with that yet
but presume that it's there to adjust bearing pre-load.

It sounds as though it is. I don't know the K.O. Lee grinders,
so I would suggest getting a manual to match *your* machine. (Perhaps
the company can supply this for you, as I believe that they are still in
business.)

If the bearings need to be replaced what are the chances of being able to do
this myslef? A manual for a slightly different KO Lee grinder suggests that
spindles must be returned to the factory for rebuilding.

I've not tried it. The spindle on my Sanford is still in pretty
good shape -- other than the seals. Oil really flows out of the spindle
bearings at the stone end.

The manual for the Sanford also suggests that if you try to
replace the bearings yourself, instead of sending it to the factory that
you are doomed to disappointment. If so, then I am probably eventually
doomed, as the factory seems to have folded not long after I got my
(very old) grinder.

Hopefully, others will pitch in with their experience, too.
When I posted, I saw only your question and no followups.

Good Luck,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

"DoN. Nichols" wrote in message
...
In article ,
Mike Henry wrote:
I recently set up a used KO Lee S714 surface grinder and was a little
disappointed at the finish, though my experience on these tools leaves a
lot
to be desired. The surface almost seems to have very shallow scallops at
regular intervals. They can't be felt by hand and a fingernail doesn't
catch
anywhere. There is a bit of noise as the grinder winds up but that seems
to
be coming mostly from the motor. The grinder appears to be in otherwise
very good condition.

Hmm ... before we get into the matter of play, I have a some
questions to ask:

1) It the motor original?

I suspect that it is a replacement - it's a GE Stock No. K163 (220 VAC,
3-phase) and looks a lot newer than the grinder.

2) If not, did you replace a three-phase motor with a single-phase
motor?

3) If it still has the original three-phase motor -- how are you
running it?

a) From genuine power company supplied three phase?

b) From a VFD?

c) From a rotary phase converter?

d) From a static phase converter?

Just a home shop here, with single-phase power, so I bought a new Hitachi
L-100 VFD for the grinder.

If your answer is either (2) or (3-d), that could be a source of
your surface finish problem.

I checked the spindle runout with a gage head and amplifier and am seeing
about 0.00075" with the gage tip on the tapered spindle nose (wheel &
collet
were puulled off and belts between spindle and motor were removed).

With the spindle warmed up, or after it has been sitting cold
for a while?

It was checked both cold and after 45 minutes of running with no discernible
difference in the readings.


I
can
also get about 0.0015" deflection in the spindle by manually pushing or
pulling the spindle toward or away from the gage tip.

Is that in the spindle bearings, or in the ways of the vertical
slide? (To tell -- shift the gauge to measure the spindle housing and
repeat the test.

Hmm - hadn't thought of that. Just cecked, though, and only get 0.0002"
deflection when the gauge tip is against the housing.

I think that your measurements may be a bit high -- but the
runout (if it is *consistent* runout, and not slop in the bearings)
would probably be tuned out when you true your wheel with a diamond.
(You *did* true it first, didn't you?)

I'm pretty sure that these readings are not a good sign. KO Lee specs their
new grinders at 0.0001" runout. The wheel was trued before taking the test
grinds. I believe that I fed the wheel about 5-10 thou into the diamond, a
a thou or less per pass, with a couple of passes at the end with no
downfeed.. FWIW, the test grind was made with a couple of tenths downfeed
per pass, with about 0.050" infeed per pass and it was sparked out at the
end.

A friend also suggested that truening the wheel would take out the slop, but
it occurss to me that a bad ball or two (needle?) could cause the wheel turn
just a little eccentrically under load. I'm wondering if that might cause a
slight wheel hop, once per revolution.


The spindle feels
reasonably cool after running for 45 minutes without a wheel or collet
mounted.

Then it at least is probably not too tight --but it might be too
loose.

This seems to be pretty far out of spec to me, but opinions would be
appreciated from those that know better than I.

Another thing to check is whether the pitch of the scallop
matches the teeth of the rack gear on the bottom of the table. If so,
then there is proably some slop in the table ways.

I'll check that out after freshly dressing the wheel again but on the sample
I have now it appears that the pitch of the scallops is about half the pitch
of the rack, maybe less..


If this does need attention, is there any chance that the bearings just
need
adjustment? There's a circular disk threaded into the outboard side of
the
spindle with holes for a pin spanner wrench. I haven't mucked with that
yet
but presume that it's there to adjust bearing pre-load.

It sounds as though it is. I don't know the K.O. Lee grinders,
so I would suggest getting a manual to match *your* machine. (Perhaps
the company can supply this for you, as I believe that they are still in
business.)

Yep, still in business, but they don't seem to have any manuals for this
model although they were happy to send me parts manual. That only has about
5 pages with a couple of sectioned views but not much detail on maintenance
or adjustments. There's virtually no detail on the spindle or bearings.
They did send me a manual for a more recent model (SE612/SE618) but that's
been of no help either.


If the bearings need to be replaced what are the chances of being able to
do
this myslef? A manual for a slightly different KO Lee grinder suggests
that
spindles must be returned to the factory for rebuilding.

I've not tried it. The spindle on my Sanford is still in pretty
good shape -- other than the seals. Oil really flows out of the spindle
bearings at the stone end.

The manual for the Sanford also suggests that if you try to
replace the bearings yourself, instead of sending it to the factory that
you are doomed to disappointment. If so, then I am probably eventually
doomed, as the factory seems to have folded not long after I got my
(very old) grinder.

Well, there is always the option of taking it to a machine rebuilder. I
know of someone somewhat local and might consider that option. I'd like to
be a little more knowledgeable on options before talking to him, though.


Hopefully, others will pitch in with their experience, too.
When I posted, I saw only your question and no followups.

Yours was the first I saw - thanks.


Good Luck,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

In article ,
says...
I recently set up a used KO Lee S714 surface grinder and was a little
disappointed at the finish, though my experience on these tools leaves a lot
to be desired. The surface almost seems to have very shallow scallops at
regular intervals. They can't be felt by hand and a fingernail doesn't catch
anywhere. There is a bit of noise as the grinder winds up but that seems to
be coming mostly from the motor. The grinder appears to be in otherwise
very good condition.

I checked the spindle runout with a gage head and amplifier and am seeing
about 0.00075" with the gage tip on the tapered spindle nose (wheel & collet
were puulled off and belts between spindle and motor were removed). I can
also get about 0.0015" deflection in the spindle by manually pushing or
pulling the spindle toward or away from the gage tip. The spindle feels
reasonably cool after running for 45 minutes without a wheel or collet
mounted.

This seems to be pretty far out of spec to me, but opinions would be
appreciated from those that know better than I.

If this does need attention, is there any chance that the bearings just need
adjustment? There's a circular disk threaded into the outboard side of the
spindle with holes for a pin spanner wrench. I haven't mucked with that yet
but presume that it's there to adjust bearing pre-load.

If the bearings need to be replaced what are the chances of being able to do
this myslef? A manual for a slightly different KO Lee grinder suggests that
spindles must be returned to the factory for rebuilding.


The runout seems excessive, .0002 max would be typical for
a new grinder spindle, and there should be virtually zero
free play, if that's what you mean by "0.0015" deflection".
Preload in something like this is not normally adjustable,
but is determined by the bearings themselves and the
spacers that separate them.

You may be able to replace the bearings yourself if you're
careful and educate yourself enough to know when to charge
ahead and when ask for help or do a bit more research. As
far as returning to KO Lee goes, there are dozens of other
spindle rebuilders who will repair virtually any spindle.

Ned Simmons

On Mon, 30 Aug 2004 20:18:14 -0500, "Mike Henry"
wrote:

I recently set up a used KO Lee S714 surface grinder and was a little
disappointed at the finish, though my experience on these tools leaves a lot
to be desired. The surface almost seems to have very shallow scallops at
regular intervals. They can't be felt by hand and a fingernail doesn't catch
anywhere. There is a bit of noise as the grinder winds up but that seems to
be coming mostly from the motor. The grinder appears to be in otherwise
very good condition.

I checked the spindle runout with a gage head and amplifier and am seeing
about 0.00075" with the gage tip on the tapered spindle nose (wheel & collet
were puulled off and belts between spindle and motor were removed). I can
also get about 0.0015" deflection in the spindle by manually pushing or
pulling the spindle toward or away from the gage tip. The spindle feels
reasonably cool after running for 45 minutes without a wheel or collet
mounted.

This seems to be pretty far out of spec to me, but opinions would be
appreciated from those that know better than I.

If this does need attention, is there any chance that the bearings just need
adjustment? There's a circular disk threaded into the outboard side of the
spindle with holes for a pin spanner wrench. I haven't mucked with that yet
but presume that it's there to adjust bearing pre-load.

If the bearings need to be replaced what are the chances of being able to do
this myslef? A manual for a slightly different KO Lee grinder suggests that
spindles must be returned to the factory for rebuilding.

TIA, Mike

Ive got the same issue with my big 6x18. Its the spindle bearings.
Shrug..the finish is good enough for my purposes as is the tolerences.
When it gets worse, Ill replace em. But Ive seen them go for years
and years and not get any worse.

Also be sure to dress your wheel as this can be a cause of that sort
of pattern..a somewhat out of balance condition.

You MAY be able to adjust preload a smidge, but then it will reduce
the life of your bearings even more.

Ive not rebuilt the spindle of a KO Lee, but they are similar to that
of a B&S, and they can be easily rebuilt by the end user.


Btw...if anyone wants a Jones and Shipman surface grinder, Ive got
access to two of them, automatic feeds, marvelous condidtion and ready
to be put to work, in Santa Ana California

The client wants $1000 and $1500 for them. One is cosmetically
prettier than the other, and both are nice.

Gunner

"She's (my daughter) already dating a sex offender.
Better that than a republican fundie neocon fascist."
FF, (alt.machines.cnc)

On Tue, 31 Aug 2004 04:57:17 +0000, Gunner wrote:


Ive not rebuilt the spindle of a KO Lee, but they are similar to that
of a B&S, and they can be easily rebuilt by the end user.

I wonder if you have the time to write up a description of rebuilding
a surface grinder's spindle, using the example of a Brown and Sharpe
machine. I've often heard that a used SG with a spindle that needs
rebuilding isn't worth purchasing because of the expense. If it's
really not that difficult to rebuild, a "How To" description of the
process could open up a new source for used surface grinders, and
I'm sure that many people would be grateful.

How's that for an imposition? :-)

new grinders at 0.0001" runout. The wheel was trued before taking the test
grinds. I believe that I fed the wheel about 5-10 thou into the diamond, a
a thou or less per pass, with a couple of passes at the end with no
downfeed.. FWIW, the test grind was made with a couple of tenths downfeed

I think that any dressing without actually removing stone hardens the wheel.
Your last pass should remove 1 thou for a 32A type wheel and about 1/2
thou for a NSG blue wheel. Check the Norton web site for tips.

chuck

This is Grant Erwin, posting less frequently these days and from Karen's
account because my PC is waiting for a new hard drive.

I bought a very used KO Lee S612 and the spindle bearings were bad. I
rebuilt my own spindle. The bearings were very expensive. KO Lee specs
Torrington/Fafnir bearings but I got New Hampshire Ball Bearings (NHBB)
instead. I relied extensively on the internal KO Lee documentation. You
should call KO Lee and ask them to speak to someone about how to rebuild
your old spindle. My contact was Doug; 605-225-5820 x175. I wrote up the
procedure I used, and here it is:

-------------

Spindle:

My spindle is No. S655C, which is real old. I'm told it uses 2 sets of
angular contact ball bearings (not tapered) each set of which is Fafnir
2MM9105CRDUME6151. (NOTE: this part number is a K.O. Lee part number from
the early 1950's, and it is not possible to obtain this any more for
several reasons. The current Fafnir part number is 2MM9105WICRDUM, which
is one set. Two sets are needed.)

Removal and Installation:

The bearings are retained by the end caps. The end caps are drilled
for face spanners although special tooling may be needed. (I sometimes
use two Vise-Grip chain wrenches .. don't know if this will work.)
The bearings are supposed to be installed DB (back to back). For
an explanation of that, see below.

The bearings are loaded by the lock nuts inside the end caps. In the front,
use a very light preload (3-5 inch pounds). In the back, tighten to
3-5 inch pounds and back off 1/8 turn to allow for thermal expansion.
After installing new bearings, check runout of the wheel taper. If
the runout exceeds .0001" (one tenth) the wheel taper needs to be
reground. Note that it may be possible to rotate the bearings in
their seats, to reduce runout, as the high runout points are marked
with an asterisk on one side.

Balancing is not necessary.

The bearings should be greased prior to use. They should be about
1/3 full only. This should be between 1 gram and 1.25 grams of
grease. A suggested grease that is widely available is Chevron SRI.
The design of the end caps should keep out coolant and grinding grit.


Addendum (from talking to Jim Goode @ Torrington/Fafnir in Bellevue,
also from talking to Doug @ K.O. Lee again)

The bearing number I need is Fafnir 2MM9105WICRDUM, which is a set
of 2, I need 2 sets. These should come with the high runout points
marked with an asterisk on one side, and with no grease on them.
Fafnir recommends that from 1.0 gram to 1.25 grams of grease (they
call out Chevron SRI, but others will work) be installed with a
finger, spread around the bearing. Fafnir cautions that the
orientation of angular contact ball bearings in the spindle is
significant. K.O. Lee says that 3 orientations of bearing are
possible: DB, DF, or DT, and that DB is called out in this spindle.

An explanation of these last terms is given in the nice URL:
http://www.ntnamerica.com/Knowledge/...ng_AngCont.htm

another good reference site is:
http://www.mmsonline.com/articles/hsm9802.html

------- end of my old notes

I went to a "tobacco shop" in Seattle's University District and bought
a very inexpensive gram scale to get the correct amount of grease. I
installed the grease using a needle attachment to my grease gun (don't
remember that part very well). I made a custom face spanner and a
lathe-turned bearing drift for this job. My spindle has runout within
spec. I have never been able to get a perfect ground finish with it;
however I rarely am looking for one. My goal is usually sub-thou
parallelism of two flat faces, and this my machine does very well.

I found working with KO Lee to be straightforward and pleasant. I
would not hesitate to try rebuilding your spindle. I should note that
over the succeeding years I have seen several NOS KO Lee grinding
spindle assemblies complete on ebay, and they have often sold for
around $100 which is only about 20% of the cost of a new set of
bearings.

Any small surface grinder should have the very edges of the wheels
eased a little bit with a dressing stone after being trued with a
diamond dresser. This helped me a lot to get a much better finish.
I also often set a smallish part at an angle to the X travel of the
surface grinder, take a pass, then without changing the Z location,
reset the part at an opposite angle and regrind. This gives a
pleasing checkered finish. It's all cosmetic - even a tenths
indicator shows no deflection whatever across the checker marks.

Grant Erwin
Kirkland, Washington



Mike Henry wrote:

I recently set up a used KO Lee S714 surface grinder and was a little
disappointed at the finish, though my experience on these tools leaves a lot
to be desired. The surface almost seems to have very shallow scallops at
regular intervals. They can't be felt by hand and a fingernail doesn't catch
anywhere. There is a bit of noise as the grinder winds up but that seems to
be coming mostly from the motor. The grinder appears to be in otherwise
very good condition.

I checked the spindle runout with a gage head and amplifier and am seeing
about 0.00075" with the gage tip on the tapered spindle nose (wheel & collet
were puulled off and belts between spindle and motor were removed). I can
also get about 0.0015" deflection in the spindle by manually pushing or
pulling the spindle toward or away from the gage tip. The spindle feels
reasonably cool after running for 45 minutes without a wheel or collet
mounted.

This seems to be pretty far out of spec to me, but opinions would be
appreciated from those that know better than I.

If this does need attention, is there any chance that the bearings just need
adjustment? There's a circular disk threaded into the outboard side of the
spindle with holes for a pin spanner wrench. I haven't mucked with that yet
but presume that it's there to adjust bearing pre-load.

If the bearings need to be replaced what are the chances of being able to do
this myslef? A manual for a slightly different KO Lee grinder suggests that
spindles must be returned to the factory for rebuilding.

TIA, Mike

(Charles A. Sherwood) wrote in message ...
new grinders at 0.0001" runout. The wheel was trued before taking the test
grinds. I believe that I fed the wheel about 5-10 thou into the diamond, a
a thou or less per pass, with a couple of passes at the end with no
downfeed.. FWIW, the test grind was made with a couple of tenths downfeed

I think that any dressing without actually removing stone hardens the wheel.
Your last pass should remove 1 thou for a 32A type wheel and about 1/2
thou for a NSG blue wheel. Check the Norton web site for tips.

chuck

I find that dressing all sides of wheels as well as the working
surface cuts out virtually all vibration on any type of mounted
grinder. Mine run almost silent and take a very long time to stop
after switching off.
Mark K.

"Charles A. Sherwood" wrote in message
...
new grinders at 0.0001" runout. The wheel was trued before taking the
test
grinds. I believe that I fed the wheel about 5-10 thou into the diamond,
a
a thou or less per pass, with a couple of passes at the end with no
downfeed.. FWIW, the test grind was made with a couple of tenths
downfeed

I think that any dressing without actually removing stone hardens the
wheel.
Your last pass should remove 1 thou for a 32A type wheel and about 1/2
thou for a NSG blue wheel. Check the Norton web site for tips.

Thanks - I'll check out Norton.

FWIW, KO Lee suggests that 1 thou downfeed is best when rapid stock removal
is desired and lesser downfeeds when one wants to approach a mirror finish.

"Ned Simmons" wrote in message
...
In article ,
says...
I recently set up a used KO Lee S714 surface grinder and was a little
disappointed at the finish, though my experience on these tools leaves a
lot
to be desired. The surface almost seems to have very shallow scallops
at
regular intervals. They can't be felt by hand and a fingernail doesn't
catch
anywhere. There is a bit of noise as the grinder winds up but that
seems to
be coming mostly from the motor. The grinder appears to be in otherwise
very good condition.

I checked the spindle runout with a gage head and amplifier and am
seeing
about 0.00075" with the gage tip on the tapered spindle nose (wheel &
collet
were puulled off and belts between spindle and motor were removed). I
can
also get about 0.0015" deflection in the spindle by manually pushing or
pulling the spindle toward or away from the gage tip. The spindle feels
reasonably cool after running for 45 minutes without a wheel or collet
mounted.

This seems to be pretty far out of spec to me, but opinions would be
appreciated from those that know better than I.

If this does need attention, is there any chance that the bearings just
need
adjustment? There's a circular disk threaded into the outboard side of
the
spindle with holes for a pin spanner wrench. I haven't mucked with that
yet
but presume that it's there to adjust bearing pre-load.

If the bearings need to be replaced what are the chances of being able
to do
this myslef? A manual for a slightly different KO Lee grinder suggests
that
spindles must be returned to the factory for rebuilding.


The runout seems excessive, .0002 max would be typical for
a new grinder spindle, and there should be virtually zero
free play, if that's what you mean by "0.0015" deflection".
Preload in something like this is not normally adjustable,
but is determined by the bearings themselves and the
spacers that separate them.

I wondered if that was the case since the manual I have doesn't mention any
adjustments.

You may be able to replace the bearings yourself if you're
careful and educate yourself enough to know when to charge
ahead and when ask for help or do a bit more research. As
far as returning to KO Lee goes, there are dozens of other
spindle rebuilders who will repair virtually any spindle.

I'd be tempted to find someone to do this for me. As it happens, I know
someone that owns a machine tool rebuilding company that is not too far from
here. He won't be cheap but he is extremely honest and experienced.


Ned Simmons

"Gunner" wrote in message
...
On Mon, 30 Aug 2004 20:18:14 -0500, "Mike Henry"
wrote:

I recently set up a used KO Lee S714 surface grinder and was a little
disappointed at the finish, though my experience on these tools leaves a
lot
to be desired. The surface almost seems to have very shallow scallops at
regular intervals. They can't be felt by hand and a fingernail doesn't
catch
anywhere. There is a bit of noise as the grinder winds up but that seems
to
be coming mostly from the motor. The grinder appears to be in otherwise
very good condition.

I checked the spindle runout with a gage head and amplifier and am seeing
about 0.00075" with the gage tip on the tapered spindle nose (wheel &
collet
were puulled off and belts between spindle and motor were removed). I
can
also get about 0.0015" deflection in the spindle by manually pushing or
pulling the spindle toward or away from the gage tip. The spindle feels
reasonably cool after running for 45 minutes without a wheel or collet
mounted.

This seems to be pretty far out of spec to me, but opinions would be
appreciated from those that know better than I.

If this does need attention, is there any chance that the bearings just
need
adjustment? There's a circular disk threaded into the outboard side of
the
spindle with holes for a pin spanner wrench. I haven't mucked with that
yet
but presume that it's there to adjust bearing pre-load.

If the bearings need to be replaced what are the chances of being able to
do
this myslef? A manual for a slightly different KO Lee grinder suggests
that
spindles must be returned to the factory for rebuilding.

TIA, Mike

Ive got the same issue with my big 6x18. Its the spindle bearings.
Shrug..the finish is good enough for my purposes as is the tolerences.
When it gets worse, Ill replace em. But Ive seen them go for years
and years and not get any worse.

In truth, the finish is probably good enough for what I need. Want is
another matter altogether, though, and that always seems to cost a lot.

Also be sure to dress your wheel as this can be a cause of that sort
of pattern..a somewhat out of balance condition.

How much should one expect to take off a new wheel? That's probably
dependent on a lot of factors, but is 10 thou in the general ballpark?

You MAY be able to adjust preload a smidge, but then it will reduce
the life of your bearings even more.

Sounds like it's best not to go there, then.

Ive not rebuilt the spindle of a KO Lee, but they are similar to that
of a B&S, and they can be easily rebuilt by the end user.

As someone else requested, how about a short desription of the process?

Btw...if anyone wants a Jones and Shipman surface grinder, Ive got
access to two of them, automatic feeds, marvelous condidtion and ready
to be put to work, in Santa Ana California

The client wants $1000 and $1500 for them. One is cosmetically
prettier than the other, and both are nice.

Gunner

"She's (my daughter) already dating a sex offender.
Better that than a republican fundie neocon fascist."
FF, (alt.machines.cnc)

Grant,

Thanks - that's a big help. I wish I had the discipline to write stuff like
that down when doing this sort of thing. Sure comes in handy later.

Do you remember the approximate cost of the bearings? Motion Industries has
an outlet close by and I'd probably go with them.

My previous contacts with KO Lee were not all that encouraging, but I'll try
Doug.

It appears that the end caps will need a non-standard face spanner (odd hole
size for the pins), but it should be easy enough to cobble up something up
that will work. It sounds like I can remove the end caps without any risk
of damaging the spindle or bearings - is that correct? Taking those off
would let me check to see if the lock nuts are loose, which would be a step
in the right direction.

Good tips in those links as well as the rest of your post.

Good luck on the hard drive - went through a failed HD myself a while back
and it wasn't pretty.

Mike

"Karen Story" wrote in message
...
This is Grant Erwin, posting less frequently these days and from Karen's
account because my PC is waiting for a new hard drive.

I bought a very used KO Lee S612 and the spindle bearings were bad. I
rebuilt my own spindle. The bearings were very expensive. KO Lee specs
Torrington/Fafnir bearings but I got New Hampshire Ball Bearings (NHBB)
instead. I relied extensively on the internal KO Lee documentation. You
should call KO Lee and ask them to speak to someone about how to rebuild
your old spindle. My contact was Doug; 605-225-5820 x175. I wrote up the
procedure I used, and here it is:

-------------

Spindle:

My spindle is No. S655C, which is real old. I'm told it uses 2 sets of
angular contact ball bearings (not tapered) each set of which is Fafnir
2MM9105CRDUME6151. (NOTE: this part number is a K.O. Lee part number from
the early 1950's, and it is not possible to obtain this any more for
several reasons. The current Fafnir part number is 2MM9105WICRDUM, which
is one set. Two sets are needed.)

Removal and Installation:

The bearings are retained by the end caps. The end caps are drilled
for face spanners although special tooling may be needed. (I sometimes
use two Vise-Grip chain wrenches .. don't know if this will work.)
The bearings are supposed to be installed DB (back to back). For
an explanation of that, see below.

The bearings are loaded by the lock nuts inside the end caps. In the
front,
use a very light preload (3-5 inch pounds). In the back, tighten to
3-5 inch pounds and back off 1/8 turn to allow for thermal expansion.
After installing new bearings, check runout of the wheel taper. If
the runout exceeds .0001" (one tenth) the wheel taper needs to be
reground. Note that it may be possible to rotate the bearings in
their seats, to reduce runout, as the high runout points are marked
with an asterisk on one side.

Balancing is not necessary.

The bearings should be greased prior to use. They should be about
1/3 full only. This should be between 1 gram and 1.25 grams of
grease. A suggested grease that is widely available is Chevron SRI.
The design of the end caps should keep out coolant and grinding grit.


Addendum (from talking to Jim Goode @ Torrington/Fafnir in Bellevue,
also from talking to Doug @ K.O. Lee again)

The bearing number I need is Fafnir 2MM9105WICRDUM, which is a set
of 2, I need 2 sets. These should come with the high runout points
marked with an asterisk on one side, and with no grease on them.
Fafnir recommends that from 1.0 gram to 1.25 grams of grease (they
call out Chevron SRI, but others will work) be installed with a
finger, spread around the bearing. Fafnir cautions that the
orientation of angular contact ball bearings in the spindle is
significant. K.O. Lee says that 3 orientations of bearing are
possible: DB, DF, or DT, and that DB is called out in this spindle.

An explanation of these last terms is given in the nice URL:

http://www.ntnamerica.com/Knowledge/...ng_AngCont.htm

another good reference site is:
http://www.mmsonline.com/articles/hsm9802.html

------- end of my old notes

I went to a "tobacco shop" in Seattle's University District and bought
a very inexpensive gram scale to get the correct amount of grease. I
installed the grease using a needle attachment to my grease gun (don't
remember that part very well). I made a custom face spanner and a
lathe-turned bearing drift for this job. My spindle has runout within
spec. I have never been able to get a perfect ground finish with it;
however I rarely am looking for one. My goal is usually sub-thou
parallelism of two flat faces, and this my machine does very well.

I found working with KO Lee to be straightforward and pleasant. I
would not hesitate to try rebuilding your spindle. I should note that
over the succeeding years I have seen several NOS KO Lee grinding
spindle assemblies complete on ebay, and they have often sold for
around $100 which is only about 20% of the cost of a new set of
bearings.

Any small surface grinder should have the very edges of the wheels
eased a little bit with a dressing stone after being trued with a
diamond dresser. This helped me a lot to get a much better finish.
I also often set a smallish part at an angle to the X travel of the
surface grinder, take a pass, then without changing the Z location,
reset the part at an opposite angle and regrind. This gives a
pleasing checkered finish. It's all cosmetic - even a tenths
indicator shows no deflection whatever across the checker marks.

Grant Erwin
Kirkland, Washington



Mike Henry wrote:

I recently set up a used KO Lee S714 surface grinder and was a little
disappointed at the finish, though my experience on these tools leaves a
lot
to be desired. The surface almost seems to have very shallow scallops
at
regular intervals. They can't be felt by hand and a fingernail doesn't
catch
anywhere. There is a bit of noise as the grinder winds up but that
seems to
be coming mostly from the motor. The grinder appears to be in otherwise
very good condition.

I checked the spindle runout with a gage head and amplifier and am
seeing
about 0.00075" with the gage tip on the tapered spindle nose (wheel &
collet
were puulled off and belts between spindle and motor were removed). I
can
also get about 0.0015" deflection in the spindle by manually pushing or
pulling the spindle toward or away from the gage tip. The spindle feels
reasonably cool after running for 45 minutes without a wheel or collet
mounted.

This seems to be pretty far out of spec to me, but opinions would be
appreciated from those that know better than I.

If this does need attention, is there any chance that the bearings just
need
adjustment? There's a circular disk threaded into the outboard side of
the
spindle with holes for a pin spanner wrench. I haven't mucked with that
yet
but presume that it's there to adjust bearing pre-load.

If the bearings need to be replaced what are the chances of being able
to do
this myslef? A manual for a slightly different KO Lee grinder suggests
that
spindles must be returned to the factory for rebuilding.

TIA, Mike

My bearings were purchased by the person who sold me the surface grinder
who warranted the spindle bearings. I don't know the price, but I expect
they were about $400-500.

To make the face spanner I just bandsawed out a flat steel plate into
the shape I needed, then drilled undersize and reamed to .0005" under
and pressed in a couple of pins. That part wasn't hard. I don't recall
the details, but later I found that a 3mm face spanner will work fine
in a 1/8" pin application, and that's probably what was called for.

You certainly won't hurt anything by removing the end caps, no. If
you carefully count the number of turns when you remove them then
you can replace them exactly, maybe. I very much doubt you are
going to fix anything by monkeying with the end caps, though. I
don't recall any "lock nuts" - on my spindle I remember the end
caps being the active member. You'll be shooting in the dark without
a good exploded diagram from K.O. Lee, though.

The hard drive failure isn't that big a deal since I do regular
backups and since I was able to get all my critical data off it.
We have a little LAN at my house, so it was just a matter of getting
my stuck disk to spin up again for a short time and copying things
furiously until it stuck again. I found that removing the drive and
putting it in the freezer (I wrapped it in a paper towel and put it
in a new quart ziploc bag so the paper would absorb moisture) for a
few hours freed it up again. I would count this as a last-ditch
effort only to be done on a drive you're abandoning. It was only
a few months old, too. No worry, the warranty replacement is on the
way and it will soon be all tight & right again.

GWE

Mike Henry wrote:

Grant,

Thanks - that's a big help. I wish I had the discipline to write stuff like
that down when doing this sort of thing. Sure comes in handy later.

Do you remember the approximate cost of the bearings? Motion Industries has
an outlet close by and I'd probably go with them.

My previous contacts with KO Lee were not all that encouraging, but I'll try
Doug.

It appears that the end caps will need a non-standard face spanner (odd hole
size for the pins), but it should be easy enough to cobble up something up
that will work. It sounds like I can remove the end caps without any risk
of damaging the spindle or bearings - is that correct? Taking those off
would let me check to see if the lock nuts are loose, which would be a step
in the right direction.

Good tips in those links as well as the rest of your post.

Good luck on the hard drive - went through a failed HD myself a while back
and it wasn't pretty.

Mike

"Karen Story" wrote in message
...

This is Grant Erwin, posting less frequently these days and from Karen's
account because my PC is waiting for a new hard drive.

I bought a very used KO Lee S612 and the spindle bearings were bad. I
rebuilt my own spindle. The bearings were very expensive. KO Lee specs
Torrington/Fafnir bearings but I got New Hampshire Ball Bearings (NHBB)
instead. I relied extensively on the internal KO Lee documentation. You
should call KO Lee and ask them to speak to someone about how to rebuild
your old spindle. My contact was Doug; 605-225-5820 x175. I wrote up the
procedure I used, and here it is:

-------------

Spindle:

My spindle is No. S655C, which is real old. I'm told it uses 2 sets of
angular contact ball bearings (not tapered) each set of which is Fafnir
2MM9105CRDUME6151. (NOTE: this part number is a K.O. Lee part number from
the early 1950's, and it is not possible to obtain this any more for
several reasons. The current Fafnir part number is 2MM9105WICRDUM, which
is one set. Two sets are needed.)

Removal and Installation:

The bearings are retained by the end caps. The end caps are drilled
for face spanners although special tooling may be needed. (I sometimes
use two Vise-Grip chain wrenches .. don't know if this will work.)
The bearings are supposed to be installed DB (back to back). For
an explanation of that, see below.

The bearings are loaded by the lock nuts inside the end caps. In the

front,

use a very light preload (3-5 inch pounds). In the back, tighten to
3-5 inch pounds and back off 1/8 turn to allow for thermal expansion.
After installing new bearings, check runout of the wheel taper. If
the runout exceeds .0001" (one tenth) the wheel taper needs to be
reground. Note that it may be possible to rotate the bearings in
their seats, to reduce runout, as the high runout points are marked
with an asterisk on one side.

Balancing is not necessary.

The bearings should be greased prior to use. They should be about
1/3 full only. This should be between 1 gram and 1.25 grams of
grease. A suggested grease that is widely available is Chevron SRI.
The design of the end caps should keep out coolant and grinding grit.


Addendum (from talking to Jim Goode @ Torrington/Fafnir in Bellevue,
also from talking to Doug @ K.O. Lee again)

The bearing number I need is Fafnir 2MM9105WICRDUM, which is a set
of 2, I need 2 sets. These should come with the high runout points
marked with an asterisk on one side, and with no grease on them.
Fafnir recommends that from 1.0 gram to 1.25 grams of grease (they
call out Chevron SRI, but others will work) be installed with a
finger, spread around the bearing. Fafnir cautions that the
orientation of angular contact ball bearings in the spindle is
significant. K.O. Lee says that 3 orientations of bearing are
possible: DB, DF, or DT, and that DB is called out in this spindle.

An explanation of these last terms is given in the nice URL:


http://www.ntnamerica.com/Knowledge/...ng_AngCont.htm

another good reference site is:
http://www.mmsonline.com/articles/hsm9802.html

------- end of my old notes

I went to a "tobacco shop" in Seattle's University District and bought
a very inexpensive gram scale to get the correct amount of grease. I
installed the grease using a needle attachment to my grease gun (don't
remember that part very well). I made a custom face spanner and a
lathe-turned bearing drift for this job. My spindle has runout within
spec. I have never been able to get a perfect ground finish with it;
however I rarely am looking for one. My goal is usually sub-thou
parallelism of two flat faces, and this my machine does very well.

I found working with KO Lee to be straightforward and pleasant. I
would not hesitate to try rebuilding your spindle. I should note that
over the succeeding years I have seen several NOS KO Lee grinding
spindle assemblies complete on ebay, and they have often sold for
around $100 which is only about 20% of the cost of a new set of
bearings.

Any small surface grinder should have the very edges of the wheels
eased a little bit with a dressing stone after being trued with a
diamond dresser. This helped me a lot to get a much better finish.
I also often set a smallish part at an angle to the X travel of the
surface grinder, take a pass, then without changing the Z location,
reset the part at an opposite angle and regrind. This gives a
pleasing checkered finish. It's all cosmetic - even a tenths
indicator shows no deflection whatever across the checker marks.

Grant Erwin
Kirkland, Washington



Mike Henry wrote:


I recently set up a used KO Lee S714 surface grinder and was a little
disappointed at the finish, though my experience on these tools leaves a

lot

to be desired. The surface almost seems to have very shallow scallops

at

regular intervals. They can't be felt by hand and a fingernail doesn't

catch

anywhere. There is a bit of noise as the grinder winds up but that

seems to

be coming mostly from the motor. The grinder appears to be in otherwise
very good condition.

I checked the spindle runout with a gage head and amplifier and am

seeing

about 0.00075" with the gage tip on the tapered spindle nose (wheel &

collet

were puulled off and belts between spindle and motor were removed). I

can

also get about 0.0015" deflection in the spindle by manually pushing or
pulling the spindle toward or away from the gage tip. The spindle feels
reasonably cool after running for 45 minutes without a wheel or collet
mounted.

This seems to be pretty far out of spec to me, but opinions would be
appreciated from those that know better than I.

If this does need attention, is there any chance that the bearings just

need

adjustment? There's a circular disk threaded into the outboard side of

the

spindle with holes for a pin spanner wrench. I haven't mucked with that

yet

but presume that it's there to adjust bearing pre-load.

If the bearings need to be replaced what are the chances of being able

to do

this myslef? A manual for a slightly different KO Lee grinder suggests

that

spindles must be returned to the factory for rebuilding.

TIA, Mike

On Wed, 1 Sep 2004 09:13:23 -0500, "Mike Henry"
wrote:

Grant,

Thanks - that's a big help. I wish I had the discipline to write stuff like
that down when doing this sort of thing. Sure comes in handy later.

Do you remember the approximate cost of the bearings? Motion Industries has
an outlet close by and I'd probably go with them.

Try Alpine Bearing in Boston Mass. They do the mailorder COD thing.
Ask for JC. Get a price. MI is often pretty expensive.


My previous contacts with KO Lee were not all that encouraging, but I'll try
Doug.

It appears that the end caps will need a non-standard face spanner (odd hole
size for the pins), but it should be easy enough to cobble up something up
that will work. It sounds like I can remove the end caps without any risk
of damaging the spindle or bearings - is that correct? Taking those off
would let me check to see if the lock nuts are loose, which would be a step
in the right direction.

Good tips in those links as well as the rest of your post.

Good luck on the hard drive - went through a failed HD myself a while back
and it wasn't pretty.

Mike

"Karen Story" wrote in message
...
This is Grant Erwin, posting less frequently these days and from Karen's
account because my PC is waiting for a new hard drive.

I bought a very used KO Lee S612 and the spindle bearings were bad. I
rebuilt my own spindle. The bearings were very expensive. KO Lee specs
Torrington/Fafnir bearings but I got New Hampshire Ball Bearings (NHBB)
instead. I relied extensively on the internal KO Lee documentation. You
should call KO Lee and ask them to speak to someone about how to rebuild
your old spindle. My contact was Doug; 605-225-5820 x175. I wrote up the
procedure I used, and here it is:

-------------

Spindle:

My spindle is No. S655C, which is real old. I'm told it uses 2 sets of
angular contact ball bearings (not tapered) each set of which is Fafnir
2MM9105CRDUME6151. (NOTE: this part number is a K.O. Lee part number from
the early 1950's, and it is not possible to obtain this any more for
several reasons. The current Fafnir part number is 2MM9105WICRDUM, which
is one set. Two sets are needed.)

Removal and Installation:

The bearings are retained by the end caps. The end caps are drilled
for face spanners although special tooling may be needed. (I sometimes
use two Vise-Grip chain wrenches .. don't know if this will work.)
The bearings are supposed to be installed DB (back to back). For
an explanation of that, see below.

The bearings are loaded by the lock nuts inside the end caps. In the
front,
use a very light preload (3-5 inch pounds). In the back, tighten to
3-5 inch pounds and back off 1/8 turn to allow for thermal expansion.
After installing new bearings, check runout of the wheel taper. If
the runout exceeds .0001" (one tenth) the wheel taper needs to be
reground. Note that it may be possible to rotate the bearings in
their seats, to reduce runout, as the high runout points are marked
with an asterisk on one side.

Balancing is not necessary.

The bearings should be greased prior to use. They should be about
1/3 full only. This should be between 1 gram and 1.25 grams of
grease. A suggested grease that is widely available is Chevron SRI.
The design of the end caps should keep out coolant and grinding grit.


Addendum (from talking to Jim Goode @ Torrington/Fafnir in Bellevue,
also from talking to Doug @ K.O. Lee again)

The bearing number I need is Fafnir 2MM9105WICRDUM, which is a set
of 2, I need 2 sets. These should come with the high runout points
marked with an asterisk on one side, and with no grease on them.
Fafnir recommends that from 1.0 gram to 1.25 grams of grease (they
call out Chevron SRI, but others will work) be installed with a
finger, spread around the bearing. Fafnir cautions that the
orientation of angular contact ball bearings in the spindle is
significant. K.O. Lee says that 3 orientations of bearing are
possible: DB, DF, or DT, and that DB is called out in this spindle.

An explanation of these last terms is given in the nice URL:

http://www.ntnamerica.com/Knowledge/...ng_AngCont.htm

another good reference site is:
http://www.mmsonline.com/articles/hsm9802.html

------- end of my old notes

I went to a "tobacco shop" in Seattle's University District and bought
a very inexpensive gram scale to get the correct amount of grease. I
installed the grease using a needle attachment to my grease gun (don't
remember that part very well). I made a custom face spanner and a
lathe-turned bearing drift for this job. My spindle has runout within
spec. I have never been able to get a perfect ground finish with it;
however I rarely am looking for one. My goal is usually sub-thou
parallelism of two flat faces, and this my machine does very well.

I found working with KO Lee to be straightforward and pleasant. I
would not hesitate to try rebuilding your spindle. I should note that
over the succeeding years I have seen several NOS KO Lee grinding
spindle assemblies complete on ebay, and they have often sold for
around $100 which is only about 20% of the cost of a new set of
bearings.

Any small surface grinder should have the very edges of the wheels
eased a little bit with a dressing stone after being trued with a
diamond dresser. This helped me a lot to get a much better finish.
I also often set a smallish part at an angle to the X travel of the
surface grinder, take a pass, then without changing the Z location,
reset the part at an opposite angle and regrind. This gives a
pleasing checkered finish. It's all cosmetic - even a tenths
indicator shows no deflection whatever across the checker marks.

Grant Erwin
Kirkland, Washington



Mike Henry wrote:

I recently set up a used KO Lee S714 surface grinder and was a little
disappointed at the finish, though my experience on these tools leaves a
lot
to be desired. The surface almost seems to have very shallow scallops
at
regular intervals. They can't be felt by hand and a fingernail doesn't
catch
anywhere. There is a bit of noise as the grinder winds up but that
seems to
be coming mostly from the motor. The grinder appears to be in otherwise
very good condition.

I checked the spindle runout with a gage head and amplifier and am
seeing
about 0.00075" with the gage tip on the tapered spindle nose (wheel &
collet
were puulled off and belts between spindle and motor were removed). I
can
also get about 0.0015" deflection in the spindle by manually pushing or
pulling the spindle toward or away from the gage tip. The spindle feels
reasonably cool after running for 45 minutes without a wheel or collet
mounted.

This seems to be pretty far out of spec to me, but opinions would be
appreciated from those that know better than I.

If this does need attention, is there any chance that the bearings just
need
adjustment? There's a circular disk threaded into the outboard side of
the
spindle with holes for a pin spanner wrench. I haven't mucked with that
yet
but presume that it's there to adjust bearing pre-load.

If the bearings need to be replaced what are the chances of being able
to do
this myslef? A manual for a slightly different KO Lee grinder suggests
that
spindles must be returned to the factory for rebuilding.

TIA, Mike





"In my humble opinion, the petty carping levied against Bush by
the Democrats proves again, it is better to have your eye plucked
out by an eagle than to be nibbled to death by ducks." - Norman
Liebmann

I think that any dressing without actually removing stone hardens the
wheel.
Your last pass should remove 1 thou for a 32A type wheel and about 1/2
thou for a NSG blue wheel. Check the Norton web site for tips.

Thanks - I'll check out Norton.

FWIW, KO Lee suggests that 1 thou downfeed is best when rapid stock removal
is desired and lesser downfeeds when one wants to approach a mirror finish.


Careful here. Downfeed is being used in two ways.
I was recommending to remove 1 thou at a time when truing the wheel.
You are talking about grinding one thou off the work piece.

The point I was trying to make is that how you true the wheel has
a significant affect on how it cuts.

chuck

"Charles A. Sherwood" wrote in message
...
I think that any dressing without actually removing stone hardens the
wheel.
Your last pass should remove 1 thou for a 32A type wheel and about 1/2
thou for a NSG blue wheel. Check the Norton web site for tips.

Thanks - I'll check out Norton.

FWIW, KO Lee suggests that 1 thou downfeed is best when rapid stock
removal
is desired and lesser downfeeds when one wants to approach a mirror
finish.


Careful here. Downfeed is being used in two ways.
I was recommending to remove 1 thou at a time when truing the wheel.
You are talking about grinding one thou off the work piece.

The point I was trying to make is that how you true the wheel has
a significant affect on how it cuts.

Sorry, I meant downfeed in the context of dressing the wheel.

In article ,
says...
On Wed, 1 Sep 2004 09:13:23 -0500, "Mike Henry"
wrote:

Grant,

Thanks - that's a big help. I wish I had the discipline to write stuff like
that down when doing this sort of thing. Sure comes in handy later.

Do you remember the approximate cost of the bearings? Motion Industries has
an outlet close by and I'd probably go with them.

Try Alpine Bearing in Boston Mass. They do the mailorder COD thing.
Ask for JC. Get a price. MI is often pretty expensive.


About $240/pair from Motion Industries for the bearings
Grant mentioned. They show only one pair of the DUM(medium
preload) in stock, but over a thousand DUL(light preload).
I'm actually surprised that the mediums are specified--I'd
expect a light preload in a grinder spindle.

Ned Simmons

Grant (or any one else),

If you have a chance and feel so inclined would you take a look at this
site:

http://member.newsguy.com/~mphenry/s...&_bearings.htm

I've uploaded some pics there along with a brief description of what has
been done and observed so far. It's a bit rambling and not especially well
organized.

I'm especially interested to find out if the spindle bearings appear to be
the proper type, or at least the one that I could get a picture of. I found
an old 1985 Fafnir catalog that provides some info on the 2MM9105WICRDUM
bearings that you referred to in an earlier post and these look similar but
I'm not sure about the reddish brown part of the bearing. Is that the (CR)
composition cage, which is apparently non-metallic? I'd also be curious to
hear what folks think of the finish on O-1 steel.

Mike

"Karen Story" wrote in message
...
My bearings were purchased by the person who sold me the surface grinder
who warranted the spindle bearings. I don't know the price, but I expect
they were about $400-500.

To make the face spanner I just bandsawed out a flat steel plate into
the shape I needed, then drilled undersize and reamed to .0005" under
and pressed in a couple of pins. That part wasn't hard. I don't recall
the details, but later I found that a 3mm face spanner will work fine
in a 1/8" pin application, and that's probably what was called for.

You certainly won't hurt anything by removing the end caps, no. If
you carefully count the number of turns when you remove them then
you can replace them exactly, maybe. I very much doubt you are
going to fix anything by monkeying with the end caps, though. I
don't recall any "lock nuts" - on my spindle I remember the end
caps being the active member. You'll be shooting in the dark without
a good exploded diagram from K.O. Lee, though.

The hard drive failure isn't that big a deal since I do regular
backups and since I was able to get all my critical data off it.
We have a little LAN at my house, so it was just a matter of getting
my stuck disk to spin up again for a short time and copying things
furiously until it stuck again. I found that removing the drive and
putting it in the freezer (I wrapped it in a paper towel and put it
in a new quart ziploc bag so the paper would absorb moisture) for a
few hours freed it up again. I would count this as a last-ditch
effort only to be done on a drive you're abandoning. It was only
a few months old, too. No worry, the warranty replacement is on the
way and it will soon be all tight & right again.

GWE

Mike Henry wrote:

Grant,

Thanks - that's a big help. I wish I had the discipline to write stuff
like
that down when doing this sort of thing. Sure comes in handy later.

Do you remember the approximate cost of the bearings? Motion Industries
has
an outlet close by and I'd probably go with them.

My previous contacts with KO Lee were not all that encouraging, but I'll
try
Doug.

It appears that the end caps will need a non-standard face spanner (odd
hole
size for the pins), but it should be easy enough to cobble up something
up
that will work. It sounds like I can remove the end caps without any
risk
of damaging the spindle or bearings - is that correct? Taking those off
would let me check to see if the lock nuts are loose, which would be a
step
in the right direction.

Good tips in those links as well as the rest of your post.

Good luck on the hard drive - went through a failed HD myself a while
back
and it wasn't pretty.

Mike

"Karen Story" wrote in message
...

This is Grant Erwin, posting less frequently these days and from Karen's
account because my PC is waiting for a new hard drive.

I bought a very used KO Lee S612 and the spindle bearings were bad. I
rebuilt my own spindle. The bearings were very expensive. KO Lee specs
Torrington/Fafnir bearings but I got New Hampshire Ball Bearings (NHBB)
instead. I relied extensively on the internal KO Lee documentation. You
should call KO Lee and ask them to speak to someone about how to rebuild
your old spindle. My contact was Doug; 605-225-5820 x175. I wrote up the
procedure I used, and here it is:

-------------

Spindle:

My spindle is No. S655C, which is real old. I'm told it uses 2 sets of
angular contact ball bearings (not tapered) each set of which is Fafnir
2MM9105CRDUME6151. (NOTE: this part number is a K.O. Lee part number
from
the early 1950's, and it is not possible to obtain this any more for
several reasons. The current Fafnir part number is 2MM9105WICRDUM, which
is one set. Two sets are needed.)

Removal and Installation:

The bearings are retained by the end caps. The end caps are drilled
for face spanners although special tooling may be needed. (I sometimes
use two Vise-Grip chain wrenches .. don't know if this will work.)
The bearings are supposed to be installed DB (back to back). For
an explanation of that, see below.

The bearings are loaded by the lock nuts inside the end caps. In the

front,

use a very light preload (3-5 inch pounds). In the back, tighten to
3-5 inch pounds and back off 1/8 turn to allow for thermal expansion.
After installing new bearings, check runout of the wheel taper. If
the runout exceeds .0001" (one tenth) the wheel taper needs to be
reground. Note that it may be possible to rotate the bearings in
their seats, to reduce runout, as the high runout points are marked
with an asterisk on one side.

Balancing is not necessary.

The bearings should be greased prior to use. They should be about
1/3 full only. This should be between 1 gram and 1.25 grams of
grease. A suggested grease that is widely available is Chevron SRI.
The design of the end caps should keep out coolant and grinding grit.


Addendum (from talking to Jim Goode @ Torrington/Fafnir in Bellevue,
also from talking to Doug @ K.O. Lee again)

The bearing number I need is Fafnir 2MM9105WICRDUM, which is a set
of 2, I need 2 sets. These should come with the high runout points
marked with an asterisk on one side, and with no grease on them.
Fafnir recommends that from 1.0 gram to 1.25 grams of grease (they
call out Chevron SRI, but others will work) be installed with a
finger, spread around the bearing. Fafnir cautions that the
orientation of angular contact ball bearings in the spindle is
significant. K.O. Lee says that 3 orientations of bearing are
possible: DB, DF, or DT, and that DB is called out in this spindle.

An explanation of these last terms is given in the nice URL:



http://www.ntnamerica.com/Knowledge/...ng_AngCont.htm

another good reference site is:
http://www.mmsonline.com/articles/hsm9802.html

------- end of my old notes

I went to a "tobacco shop" in Seattle's University District and bought
a very inexpensive gram scale to get the correct amount of grease. I
installed the grease using a needle attachment to my grease gun (don't
remember that part very well). I made a custom face spanner and a
lathe-turned bearing drift for this job. My spindle has runout within
spec. I have never been able to get a perfect ground finish with it;
however I rarely am looking for one. My goal is usually sub-thou
parallelism of two flat faces, and this my machine does very well.

I found working with KO Lee to be straightforward and pleasant. I
would not hesitate to try rebuilding your spindle. I should note that
over the succeeding years I have seen several NOS KO Lee grinding
spindle assemblies complete on ebay, and they have often sold for
around $100 which is only about 20% of the cost of a new set of
bearings.

Any small surface grinder should have the very edges of the wheels
eased a little bit with a dressing stone after being trued with a
diamond dresser. This helped me a lot to get a much better finish.
I also often set a smallish part at an angle to the X travel of the
surface grinder, take a pass, then without changing the Z location,
reset the part at an opposite angle and regrind. This gives a
pleasing checkered finish. It's all cosmetic - even a tenths
indicator shows no deflection whatever across the checker marks.

Grant Erwin
Kirkland, Washington



Mike Henry wrote:


I recently set up a used KO Lee S714 surface grinder and was a little
disappointed at the finish, though my experience on these tools leaves
a

lot

to be desired. The surface almost seems to have very shallow scallops

at

regular intervals. They can't be felt by hand and a fingernail doesn't

catch

anywhere. There is a bit of noise as the grinder winds up but that

seems to

be coming mostly from the motor. The grinder appears to be in
otherwise
very good condition.

I checked the spindle runout with a gage head and amplifier and am

seeing

about 0.00075" with the gage tip on the tapered spindle nose (wheel &

collet

were puulled off and belts between spindle and motor were removed). I

can

also get about 0.0015" deflection in the spindle by manually pushing or
pulling the spindle toward or away from the gage tip. The spindle
feels
reasonably cool after running for 45 minutes without a wheel or collet
mounted.

This seems to be pretty far out of spec to me, but opinions would be
appreciated from those that know better than I.

If this does need attention, is there any chance that the bearings just

need

adjustment? There's a circular disk threaded into the outboard side of

the

spindle with holes for a pin spanner wrench. I haven't mucked with
that

yet

but presume that it's there to adjust bearing pre-load.

If the bearings need to be replaced what are the chances of being able

to do

this myslef? A manual for a slightly different KO Lee grinder suggests

that

spindles must be returned to the factory for rebuilding.

TIA, Mike

In article ,
says...
Grant (or any one else),

If you have a chance and feel so inclined would you take a look at this
site:

http://member.newsguy.com/~mphenry/s...&_bearings.htm

I've uploaded some pics there along with a brief description of what has
been done and observed so far. It's a bit rambling and not especially well
organized.

I'm especially interested to find out if the spindle bearings appear to be
the proper type, or at least the one that I could get a picture of. I found
an old 1985 Fafnir catalog that provides some info on the 2MM9105WICRDUM
bearings that you referred to in an earlier post and these look similar but
I'm not sure about the reddish brown part of the bearing. Is that the (CR)
composition cage, which is apparently non-metallic?

It looks like the retainer to me.

If this were my spindle and I didn't need to have it
running tomorrow, this is what I'd do. Disassemble it, take
careful note of how it's built and make sure you understand
why. Take lots of photos in case you need to ask questions.
Make sure to keep the paired bearings together thru the
whole process.

Wash the bearings thoroughly, inspect them carefully under
a stereo microscope for any obvious damage or wear to the
balls and races. Assuming they aren't obviously NFG, give
them a final rinse in clean acetone and regrease.

Reassemble the spindle. If they're identical, switch the
two pairs of bearings, back pair to the nose. The bearings
at the nose likely take more abuse than the back pair and
have more effect on the runout.

Worst case, the spindle will be no better than when you
started, but you'll have learned something and had a
practice run rebuilding the thing without jeopardizing an
expensive set of new bearings. If you've lived a clean life
and help old ladies cross the street, the runout may be
improved.

Ned Simmons

"Ned Simmons" wrote in message
...
In article ,
says...
Grant (or any one else),

If you have a chance and feel so inclined would you take a look at this
site:

http://member.newsguy.com/~mphenry/s...&_bearings.htm

I've uploaded some pics there along with a brief description of what has
been done and observed so far. It's a bit rambling and not especially
well
organized.

I'm especially interested to find out if the spindle bearings appear to
be
the proper type, or at least the one that I could get a picture of. I
found
an old 1985 Fafnir catalog that provides some info on the 2MM9105WICRDUM
bearings that you referred to in an earlier post and these look similar
but
I'm not sure about the reddish brown part of the bearing. Is that the
(CR)
composition cage, which is apparently non-metallic?

It looks like the retainer to me.

Thanks - for some odd reason it looked like an O-ring at first, which made
no sense at all.

If this were my spindle and I didn't need to have it
running tomorrow, this is what I'd do. Disassemble it, take
careful note of how it's built and make sure you understand
why. Take lots of photos in case you need to ask questions.
Make sure to keep the paired bearings together thru the
whole process.

Wash the bearings thoroughly, inspect them carefully under
a stereo microscope for any obvious damage or wear to the
balls and races. Assuming they aren't obviously NFG, give
them a final rinse in clean acetone and regrease.

Reassemble the spindle. If they're identical, switch the
two pairs of bearings, back pair to the nose. The bearings
at the nose likely take more abuse than the back pair and
have more effect on the runout.

Worst case, the spindle will be no better than when you
started, but you'll have learned something and had a
practice run rebuilding the thing without jeopardizing an
expensive set of new bearings. If you've lived a clean life
and help old ladies cross the street, the runout may be
improved.

That sounds like a reasonable approach. A knowledgeable friend is willing
to stop by and check it (and my grinding technique) out in a week or two,
so I'll probably wait until then to dig into the spindle. It's been
suggested to me that the runout characteristics (max and min just about
exactly 180° apart) indicate that the spindle may be slightly bent. If
that's true, working on the bearings probably won't help, but then dressing
the wheel sufficiently should eliminate any eccentricity that would cause
scalloping.

Someone else though that the table rack or gear may have some sort of
problem that is contributing to or causing the scalloping. I'll check that
out tomorrow night after work. At least the rack would (probably) be
cheaper than new bearings, but it won't do any thing to reduce the run out.