I am not finding any National/International Standard for the method of calibrating a Bore Indicator as a full unit,that is,including dial Gauge and Stem assembly.The method followed by us is as below:

- Assemble the Dial Gauge to the Stem of Bore Indicator unit such that the small needle of the Dial Gauge is at "1" and big needle of the Dial Gauge is at"0".
- Move the the measuring plunger of the Bore indicator with a precise (10 time accurate) micrometer and find out the deviations at every 1/10th. of the revelution of the Dial indicator till the travel of the plunger stops.

Is the method OK?.If so, what is the accepting criteria? Is there any International Standard?

I do not see a problem with your method of calibrating that type of bore gage(as long as the process is documented and everyone checking them is doing it the same way) As far as I know there is not any standard for them. Our lab uses the Dial Indicator tolerances from Navair procedure(+/- 1 Division as a rule of thumb). But the ultimate decision is the customers.


Hope this helps,
Wolf

Though no longer an active military standard you could use the MIL-STD-120, "Gage Inspection" for this calibration. Free copy can be obtained from dodssp.daps.dla.mi

Added in edit by Moderator:
"I was unable to make link work. I am not sure whether we have a copy of MIL-STD-120 here in the Cove or not. As a government document, it is copyright free. Do not be a fool and pay for a copy. I have a clean copy in my files, but it is 6.3 meg - too big to add as attachment without Marc's help. There is no "version" since U.S. Government has declared all these Standards obsolete, but that doesn't mean the techniques shown are NOT valid.

Until I work out a deal with Marc, I will email a copy (pdf) to anyone who needs it - contact me by email through my Profile.

In the meantime, I'll hope someone with time and patience can extract the pertinent pages to cover this thread's query."-Wes Bucey

See the Military Standards directory (http://elsmar.com/pdf_files/Military%20Standards/) in the pdf_files directory. It's in there. If anyone has anythng they want to contribute in the way of mil specs you can e-mail them to me and I'll put them there.

Sorry looks like I did not copy full link to the "The Department of Defense
Single Stock Point (DODSSP) for Military Specifications, Standards
and Related Publications" Web site. Try this one [url]http://dodssp.daps.dla.mil/ or just do a Google on the DODSSP name.