Bore Gage and Adjustable Set Master

[drgnrider]

I am new to calibration and trying to train myself in the art. As I have needed them, I have acquired 'how to' procedures from wherever I could off the internet. Now I need a procedure for “legacy” Bore Gages and adjustable Set Masters.

The way I see to do them: the Set Master, Bore Gage, and dial indicator are all brought in together, (on a two-year cycle). The dial indicator is removed from the Bore Gage, its’ back removed and insides cleaned and lubed, reassembled, then verified with a bench micrometer for accuracy (+/- .0001” per .030”). The remainder of the Bore Gage assembly and Set Master are disassembled, cleaned, lubed, and everything put back together. The Bore Gage and dial are then operated for functionality.

As these are adjustable for different parts, I am not sure they can be “calibrated” but more of just cleaned and visually inspected for wear and completeness. I believe this as Mitutoyo informed me that calibrating each Inside Micrometer rods is futile since the rods, when each person assembles them, will not necessarily read the same, so only the “head” can really be calibrated.

Since we are ISO 9001-2008 certified, I need to have solid reasons for why things are being done the way they are. If anyone has written procedures and/or ideas, they would be greatly appreciated.

Additionally, any ideas on books and/or classes that would be very beneficial for a calibration novice?

Thank you for your input.

 

[Jen Kirley]

Welcome to the cove!

You are certainly going about your calibration effort with thought and energy. Unless my gauges were exposed to grime/oil/dust that impaired their function, I didn't disassemble them. I checked their ability to measure within the expected parameters using traceable standards.

I agree with Mitutoyo.

Bore gauges may benefit with repeatability & reproducibility studies to help ensure they are performing consistently and their users are obtaining consistent readings.

 

[drgnrider]

Jennifer.

Unless my gauges were exposed to grime/oil/dust that impaired their function, I didn't disassemble them.

While in use, these gages are kept at their point of use, the machine. The storage boxes are left open and the gages get coated with grime, oil, dust, coolant, etc. When not in use, they are on shelves on the shop floor. 90% of all my gages, and all of these, are "legacy" (circa 1970's & 80's) and repair parts are slim, so I need to try to make them last, cleaning them helps, replacing them... is... well... OUT of the question.

Bore gauges may benefit with repeatability & reproducibility studies to help ensure they are performing consistently and their users are obtaining consistent readings.

This is why I use the Bench Micrometer to check the dial indicator when they come in to me.

Have anything documented regarding these types of tools? I have a new QA manager and he's trying to understand all of this, (especially since the gages are older than he is). The tools I am requesting to have replaced have pretty much blown his budget and we still have 6-months to go in the fiscal year!

 

[Jen Kirley]

I see. Okay, I did a search using key word "calibration" in the Post Attachments List - see the green button in the header - and came up with this list of attachments. It's quite a list, I hope there is something in there you can use. if you find something that gets you part way, feel free to adapt it to your use and share the result with us - these attachments are open source.

As far as manuals go, if I was in your position I would be doing an exhaustive Google search for your equipment's manuals first, and don't forget Amazon.com or Google Books for ideas. I get most of my books used when I can, and I've seen a lot of manuals online. When doing a Google search, try using a phrase instead of a single word in your search field and leave off the "s" or "er" etc., to broaden the search results.

As far as a calibration program goes, I believe the list of attachments I am sending you to includes an example process document. But they are for reference only - your program should suit your organization's needs, not someone else's.

I hope this helps!