# Field test for a digital dial indicator



## better-lathe-than-never (Nov 16, 2021)

I'm looking to buy a Mitutoyo Absolute Digital gauge off CL - it has a .5'' range.   Is there a quick field test that I can do to roughly check its accuracy before committing to purchase?

I have another cheap Chinese indicator that I could bring along if necessary but not sure about its accuracy either, which makes it hard to determine accuracy of anything else.

UPDATE:  I also have a magnetic base with a holding arm (vertical and horizontal).


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## macardoso (Nov 16, 2021)

You could set it up as a drop gage and check the difference between different blocks in a calibrated gage block set. I'm assuming this is a standard dial indicator.

This is a drop indicator setup.


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## better-lathe-than-never (Nov 16, 2021)

I should have mentioned that I have have an indicator magnetic base but I don't have a granite block or drop indicator setup like that above.  I'll have to look for something that I have which is measurable and exact.


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## Chewy (Nov 18, 2021)

I use gauge blocks and Mic standards to test everything that I buy.  In your case. take a piece of steel and do a precision measurement and see if the indicator reads the same.  Be careful at this time of year to make sure that the steel and indicator are both at room temperature.  I bought a Mic last year and it was about 40 degrees in the mailbox.  Took it inside and checked a standard and was off .003.  An hour later when warmed p, it was in a couple of tenths.

If you need a flat plate for a base, bring along a piece of glass.


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## Rex Walters (Nov 29, 2021)

Chewy said:


> I use gauge blocks


Pin gauges make much cheaper standards. Individual sizes can be had for a few bucks apiece, and even off-shore cheap ones will be more accurately dimensioned than even the best calipers can reliably measure. Any decent micrometer set will include standards as well.  https://www.amazon.com/dp/B01BHHK2M0/ref=cm_sw_em_r_mt_dp_BSCR53DZ7QMVHV8QNEMN


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