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John Doe[_4_] John Doe[_4_] is offline
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Default Micrometer time!

Spehro Pefhany wrote:

John Doe wrote:
Spehro Pefhany wrote:
John Doe wrote:
Spehro Pefhany wrote:
John Doe wrote:
Spehro Pefhany wrote:


But, as of a few weeks ago, I have DROs on the lathe and mill, so
digital maybe makes more sense.


DRO = "digital readout"

The lathe uses output from a micrometer?

I'm going to make a measurement with the micrometer, find the
difference from the desired measurement, and then move the tool some
number of tenths of a mm, say to take up half the difference and
leave enough for a finishing pass.

Is that what the data output on some micrometers is for?

No, AFAIUI, it's for SPC (statistical process control) where samples
are measured, recorded, and mean/standard deviations and trend lines
calculated to figure out when things have to be jiggered before the
parts start to go out of spec.

https://www.mscdirect.com/betterMRO/...ing-production

Of course if you have a lot of critical measurements and a big budget
you'll use a coordinate measuring machine (CMM) that automatically
probes the parts with a little sapphire ball.

https://ecatalog.mitutoyo.com/CRYSTA...CMM-C1840.aspx


They have data output on some ordinary digital micrometers.

This one's on sale, Mitutoyo 293-340-30, $127 (USA)...

https://www.amazon.com/gp/product/B00MBHXWGY/

"Measurement data output function is available with a water-resistant
connection cable." (the cable might be extra)


It's there to collect inspection data, as I said.


Oh. So the micrometer data output doesn't go to a lathe or a mill.