Warning about Deltronic Gage Pins - The "Certification of Accuracy" document

[GFish]

Please be aware that when you purchase Deltronic Gage Pins, the "Certification of Accuracy" document that accompanies them is not valid for calibration and new gage pins must be calibrated before use in order to meet ISO 9001 and/or ISO 13845 requirements.

Per the applicable standard - the requirement is for traceability to national or internal standards, in the US this of course is NIST. To establish this traceability, I (our 3rd party Orion Auditor) looks for an unbroken chain of calibration, validated through, at a minimum, the identification of the standards used, and their calibration information provided on a calibration certificate.

As this information is not included on Deltronic's certificate of accuracy, traceability to NIST is not evident.

As a result of this - both of the facilities that I work at received minor non-conformances requiring corrective action which seems to only include - send these out for calibration by someone who provides you with traceability to NIST. Deltronic's response to this issue that I brought to their attention was that a "long form certificate" is available for a premium charge.

Problem that I have is - how would anyone know that they need a long form cert to begin with? Seems that Deltronic's is playing on the ignorance of Quality professionals.

I just wanted people to be aware of this issue in order to prevent potential ISO 3rd party findings at their companies.

 

[Al Rosen]

Please be aware that when you purchase Deltronic Gage Pins, the "Certification of Accuracy" document that accompanies them is not valid for calibration and new gage pins must be calibrated before use in order to meet ISO 9001 and/or ISO 13845 requirements.

Per the applicable standard - the requirement is for traceability to national or internal standards, in the US this of course is NIST. To establish this traceability, I (our 3rd party Orion Auditor) looks for an unbroken chain of calibration, validated through, at a minimum, the identification of the standards used, and their calibration information provided on a calibration certificate.

As this information is not included on Deltronic's certificate of accuracy, traceability to NIST is not evident.

As a result of this - both of the facilities that I work at received minor non-conformances requiring corrective action which seems to only include - send these out for calibration by someone who provides you with traceability to NIST. Deltronic's response to this issue that I brought to their attention was that a "long form certificate" is available for a premium charge.

Problem that I have is - how would anyone know that they need a long form cert to begin with? Seems that Deltronic's is playing on the ignorance of Quality professionals.

I just wanted people to be aware of this issue in order to prevent potential ISO 3rd party findings at their companies.

PO can state that a calibration certificate traceable to NIST or other national recognized standards is required. Most manufacturers add on fees for traceable certs.

 

[GFish]

PO can state that a calibration certificate traceable to NIST or other national recognized standards is required. Most manufacturers add on fees for traceable certs.

Good point Al.
Deltronic only sells through distributors. I checked and all POs issued included requirement for cert traceable to NIST. Seems that both Deltronic and distributors do not understand ISO requirements.

 

[Jim Wynne]

Good point Al.
Deltronic only sells through distributors. I checked and all POs issued included requirement for cert traceable to NIST. Seems that both Deltronic and distributors do not understand ISO requirements.

The Deltronic website says this about certification/traceability:

We take gages seriously. National Institute of Standards and Technology (NIST) Calibrated Masters Certification of Accuracy and traceability to the NIST is included with every Deltronic gage. This no-charge feature has its foundation in masters calibrated for us by the National Institute of Standards and Technology.

 

[Michael_M]

.......Problem that I have is - how would anyone know that they need a long form cert to begin with? Seems that Deltronic's is playing on the ignorance of Quality professionals.

I just wanted people to be aware of this issue in order to prevent potential ISO 3rd party findings at their companies.

A simple solution to this is to verify pins prior to use with a traceable calibrated gage. Our procedure is to validate the gage pin with a calibrated digital micrometer before using. Just make sure that everyone knows how to use the micrometer and you will not have to spend money calibrating the gage pins, unless you are working under some requirement that requires gage pins to be calibrated. We have some custom gage pins used as 'masters' so they are calibrated by an outside lab, but if they are just used to check acceptance, use a good micrometer to validate.

 

[GFish]

A simple solution to this is to verify pins prior to use with a traceable calibrated gage. Our procedure is to validate the gage pin with a calibrated digital micrometer before using. Just make sure that everyone knows how to use the micrometer and you will not have to spend money calibrating the gage pins, unless you are working under some requirement that requires gage pins to be calibrated. We have some custom gage pins used as 'masters' so they are calibrated by an outside lab, but if they are just used to check acceptance, use a good micrometer to validate.

Another good thought Michael but the accuracy of Deltronic gages requires that they be checked with a laser micrometer which we don't have and is not cheap.

 

[Michael_M]

GFish, We use a digital OD micrometer to verify as we hold this device to a calibration of ±.0001. However, if this is not good enough, I know Mitutoyo makes a digital Micrometer that has an accuracy rating of .00002 (Mitutoyo part number 293-130-10). The last time I priced this device it was about $1,600. I don't know how many pins you have to calibrate, but the device might pay for itself in the short term (if each pin cost $20.00 to calibrate, as soon as you do 80 pins, it has paid for itself).

 

[dwperron]

First, I have reviewed more calibration certificates than I want to remember.
Even with the best of them you rarely see any that exhibit an unbroken chain of calibration to a national lab, validated through, at a minimum, the identification of the standards used, and their calibration information provided on a calibration certificate. And those would typically be physical / dimensional devices only. Normally you will get a traceability statement, but in order to demonstrate actual traceability you would need to have them trace each item used in the calibration back individually through all of their calibration sources as well. I've had to do that a few times, and it can be a painful endeavor.
If traceability is important to you then deal with 17025 accredited labs. They have proven their traceability to independent auditors.

Also, the tolerances on Deltronics plugs are +40 µin / -0. A supermike can be barely adequate for this. Lasermikes are not up to this job. And at Class X accuracy the environment is a critical factor in the measurements. Add the time you spend calibrating and it gets less cost effective to calibrate them yourself. Then when you add all of the back end costs of running a calibration facility it becomes obvious - unless calibration is a main part of your business then leave it to the experts.

 

[mr500]

So when the labs verify a pin gage, is it recorded as Maximum Inscribed / Minimum Circumscribed Circle taking the 3 largest or smallest points???
Or do they use a least squared approach?

 

[dwperron]

So when the labs verify a pin gage, is it recorded as Maximum Inscribed / Minimum Circumscribed Circle taking the 3 largest or smallest points???
Or do they use a least squared approach?

On plug gauges like Deltronics you would typically report the diameter at each end and the center then the same points rotated 90°.
Class Z or ZZ pin gauges are often just checked for diameter at each end.