What's your spindle runout?

[sc0ch]

If you have a tenths indicator or better, what's runout on the spindle nose of your lathe and/or mill (Precision Matthews or otherwise)?

1) My PM-25 has unmeasurable runout with a tenths indicator despite substantial abuse. Approximately 0.00001" on the spindle nose without load (10 millionths). Wow! Its weaknesses likely lie elsewhere (for example PM-25 vs PM-728 )

2) At work we have a Taiwanese South Bend G-26-T with approximately 0.00001" runout on the spindle nose without load (10 millionths) (Taiwanese South Bend). Wow!

3) Conversely, my clapped out "toolroom" Colchester Chipmaster is 0.00009" (90 millionths) on the spindle nose without load. It inherently cuts a 0.001" taper or worse over ten inches (Chipmaster).

4) Recently inspected a Nardini 1440 with 0.0001" (100 millionths) runout without load.

5) a used Sharp clone of a Hardinge HLV-H showed 0.00002" runout on the spindle nose without load before it sold for $15,000.

Will measure some HAAS CNC machines at work when there's time.

 

[macardoso]

I personally question (no offense intended) how you are measuring runout down to 0.00001". I consider myself to have a well stocked shop in terms of metrology instruments and I wouldn't give you a number with any certainty beyond 1 tenth (and even that is iffy since I don't send my instruments for annual calibration). Also I only have Noga bases for spindle measurements when throws all that in the garbage anyways. I know there are dial comparators that go down to 0.00002" but even then... Those numbers are in the range of interferometric measurements and all the fiddlyness that comes with measuring that precisely.

But if you really have a mill with a 10 millionths spindle TIR, good for you. I'd love that in my shop. My mill spindle has always been a tricky thing to use tiny tooling with.

Anyways...

2013 Grizzly G0704, Angular Contact bearing replacement - 0.0003" TIR. Stock roller bearings were about 0.0004" TIR. The error is in the taper grind not the bearings.
1994 Enco 110-2033 (12x36" lathe) - 0.0001-0.0002" TIR. Can be improved by tightening the spindle locknuts with extra heating and wear.

Measured with a 0.0001" DTI last calibrated in 2018.

 

[mmcmdl]

What's all this talk of millionths ?

 

[sc0ch]

I agree with the dubiousness of measuring below a tenth. Thus why I say "approximate" so frequently! However, all my measurements were repeatable with the same gauge. So, call them "gauge relative." It's just interesting to inspect this stuff and surprising sometimes.

 

[woodchucker]

I'd like to have what your smoking.
All these machines with NO RUNNOUT.

 

[mmcmdl]

I'm interested in measuring the garden out back although I do want to measure a bunch of Jacobs chucks . I'll be moving the block for the tenth time now ! with this garden My son said the next move they will be moved to the dump , although they're easy to bury .

 

[UMDJesse]

What should the acceptable runout be on the spindle?

 

[C-Bag]

3) Conversely, my clapped out "toolroom" Colchester Chipmaster is 0.00009" (90 millionths) on the spindle nose without load. It inherently cuts a 0.001" taper or worse over ten inches (Chipmaster).

I'm not a pro by any stretch, but this points out how spindle runout is just one of many factors in the work a machine will put out. I would bet big time this taper is more about twist of the bed than runout. YMMV.

 

[woodchucker]

Dave, I must be near sc0ch's smoke , I didn't understand your last post at all...

 

[mmcmdl]

Dave, I must be near sc0ch's smoke , I didn't understand your last post at all...

It was about what gets measured at my place lately . And it's NOT spindles .