Micrometer Calibration - Seeking actual Calibration Procedure for 0-1" Micrometer

[dbulak]

What is the name or number of the actual calibration procedure of a 0-1" micrometer? Where can I get it?

[Jstain1]

http://gidep-data.gidep.org/link/database

Here's a place, but you have to be a member. perhaps someone would be willing to send a procedure to you.

The number would be 33K6-4-15-1,

I'm sure there are ones you can purchase, I would consider Mitutoyo as a source.

[TeeTV]

Our company do customise calibration procedures for Micrometer, to fulfill ISO/IEC 17025 requirements. We were thinking of making them for online sales that you can use it immediately as your in-house procedure. (This type of calirbation is quite standard.) Will you be interested?


TeeTV

[Govind]

dbulak: Not meant to hijack your original thread, apologies.

JStain1,
We dont have that procedure 33K6-4-15-1. We custom developed internal procedure for our micrometers.
Just curious about one point; while measuring master between between the anvils,Is there any mention about "Number ratchet rotations"?
I was told by a senior metrologist from the old school as 2 clicks. About right?
Govind.

[TeeTV]

Govind,

We do 2 soft rotations between thumb and the pointing finger when the anvils about touching the object. Remember, soft and slow clicks.


Best regards,
Tee TV

[Jstain1]

Most established labs have a procedure in place. The more "robust" labs have access to GIDEP, where there's 1,000's of procedures, so I'm not really not in need of a procedure.

I'm sure I'll get differing opinions on this, but most of the Air force procedures are ISO17025 compliant, with the Issue of uncertainty being the biggest sticking point. I think that even that isn't a big issue.

The rule of thumb for tension is from 2 to 3 gentle turns. I've been through the Air force as well as NAVY and Mitutoyo training, and not suprising I was taught differently at each.

So, in general terms I would imagine there may be a market for procedures, but I think it would be a small niche.

Thermometers can get to be a bit involved, given the various standards that are available. I think, IMHO, that this may be very problematic.

Would you offer a "garantee" of sorts that the procedure would be compliant to some standard? if so, then your going to have to resolve this with the various certifying agencys, I.E. A2LA, NVLAP and LAB.

[Hershal]

Just a few notes......

The military procedures (USAF T.O. 33K and USN 17-20 & 17-50 series) may not necessarily be compliant to ISO/IEC 17025 in all details, uncertainty being the main sticky point, but they are extensively validated, and so we do accept them for accreditation.

I believe our colleague organizations (A2LA, NVLAP, and even L-A-B and ACLASS) also accept the military procedures for the same reason. Incidentally, the other AB not mentioned is IAS, the oldest AB in the U.S.

Marc, forgive me for blowing our horn, just want to make sure we are not overlooked.

Hershal

[Govind]

Jstain,
I did enjoy your humor about"Micrometers are not expensive "C" Clamps" pertaining to number of ratchet rotations. Also thanks to both yourself and TeeTv for providing clarity on the number of turns. But both of you did not confirm if this practice is a "thumb rule" or written standard guidelines.

This will matter for digital micrometer calibration as the display start to move back and forth couple of microns depending on the torque through ratchet rotation.I dont see this issue with mechanical micrometers though.

Govind.