MSA for Push and Pull test

[ElenR]

We received a Minor NC due to no MSA conducted on our Push and Pull Test from our IATF Surveillance audit.
We told the auditor that the bonding force is not classified as special characteristics on the control plan thereby the push and pull tester will not require mandatory MSA. But the auditor said that MSA applies to any type of measurement, inspection, and testing referenced in the Control Plan. It's just that those with SC needed to be prioritized. Is it valid that the push n pull tester need to undergo MSA?

Our bonding force check is sampling check to ensure our ferrite core will not be detached from its base after it undergone curing process.

 

[Ninja]

Howdy ElenR,

I won't answer your question directly, though I'm sure others will.
I will however walk down a train of thought...

"Our bonding force check is sampling check to ensure our ferrite core will not be detached from its base after it undergone curing process. "
Do you care about the results of the test?
"No" = stop doing the test
"Yes" = next question:

Do you care if the test is accurate?
"No" = stop doing the test
"Yes" = next question:

How do you know your test is accurate?

In automotive..."Accuracy" in a customer or auditor's eyes is almost always answered by GR&R.
I'm sure there are other valid answers to the question...by why not just answer it in the parlance of the field?
This is one of the (many) areas that I have found it cheaper and more efficient to just comply rather than to prove that another method is valid.
You can make a stand, and prove your point (over and over and over and over and over) ... or just do the GRR.

HTH

 

[Miner]

@Ninja I agree with the intent of your post, but want to make a correction:

• Accuracy - also known as bias or a measure of the location of the measurements. This is measured by a bias, linearity or stability study and is controlled by calibration.
• Precision - a measure of the variation or spread of the measurements. This is measured by an R&R study.

To quote another cover's tagline: "Because words have meaning."

 

[Ninja]

You are completely correct.

I used the word "Accuracy" since it is the only word I've ever heard automotive personnel use when asking about a vendor test method "Is it good enough to meet our needs".

Words have meaning...and it's fairly typical for folks to use them incorrectly.
Thank you for the clarification.

 

[ElenR]

@Ninja I agree with the intent of your post, but want to make a correction:

• Accuracy - also known as bias or a measure of the location of the measurements. This is measured by a bias, linearity or stability study and is controlled by calibration.
• Precision - a measure of the variation or spread of the measurements. This is measured by an R&R study.

To quote another cover's tagline: "Because words have meaning."

If I understood it right, the nonconformity statement should not No MSA since our Push and Pull Test undergone calibration but we failed to conduct R&R study, By the way, thank you for the clarification.

 

[Ninja]

Hello again ElenR,

Calibration and MSA study are two different things.

"Calibration" is verifying to a known good value (typically NIST traceable) that the equipment has the ability to measure accurately (See Miner's definition above).

MSA study considers both the equipment and how you use it (the complete test method).

If you've only calibrated the gage but then use it poorly, or if it is simply not the right tool for the job, you can totally fail MSA with a newly calibrated tool.

I've seen many tools that were calibrated, then used with no idea (no GRR) if the results meant anything or not.

 

[catalyst169]

We received a Minor NC due to no MSA conducted on our Push and Pull Test from our IATF Surveillance audit.
We told the auditor that the bonding force is not classified as special characteristics on the control plan thereby the push and pull tester will not require mandatory MSA. But the auditor said that MSA applies to any type of measurement, inspection, and testing referenced in the Control Plan. It's just that those with SC needed to be prioritized. Is it valid that the push n pull tester need to undergo MSA?

Our bonding force check is sampling check to ensure our ferrite core will not be detached from its base after it undergone curing process.

What kind of MSA study did you end up using?

 

[WEAVER]

@Ninja I agree with the intent of your post, but want to make a correction:

• Accuracy - also known as bias or a measure of the location of the measurements. This is measured by a bias, linearity or stability study and is controlled by calibration.
• Precision - a measure of the variation or spread of the measurements. This is measured by an R&R study.

To quote another cover's tagline: "Because words have meaning."

Are BIAS, LINEARITY AND STABILITY STUDIES required for every calibration? Like in some of our calibrated instruments there is only one test point -- we are not required to calibrate it in other measurement range since it's application is that test point only; so we don't have the data for linearity. Are we now required to calibrate it in it's full range since we need to evaluate its linearity?
How can we confirm (and prove to auditors and customers) that our calibration plan conforms to these three parameters?
Thanks in advance,

 

[Miner]

I recommend that you perform a risk assessment for the risk of not performing a linearity study for an instrument with a single test point. If the risk is low, skip the linearity evaluation and include your risk assessment with the records for this instrument.

 

[WEAVER]

I recommend that you perform a risk assessment for the risk of not performing a linearity study for an instrument with a single test point. If the risk is low, skip the linearity evaluation and include your risk assessment with the records for this instrument.

Thank you so much, sir, this has been most helpful!