Artifact kit to facilitate MSAs?]]>

Is it possible to obtain all the results and then we have distinguishable measurement categories? And how does it relate to PV, for example?

I have an example to measure 100mm +/- 1mm (tolerance)

I measure it with a caliper with an accuracy of 0.01 mm

So in this case I have over 200 possible results and they will be within tolerance?]]>

The gage R and R is a bit not intuitive. Can anyone explain how to derive the formula e.g. EV = mean of Range x K1. What is this constant K1 and how to derive that? why do we need to multiply by a constant when we already got the range average?

Other formulas such as AV too.

Thank you.]]>

The purpose to do so because it is difficult to maintain the sample to be in the original condition for future

GRR since the sample will have oxidation, contamination etc.

I am not sure if this practice is acceptable in view of customers and auditors.

Please enlighten me.]]>

I have a doubt about the validity of MSA studies.

According to the IATF it is not necessary to carry out this study annually. If there is no change in design, equipment and the same people are measuring, is this study valid forever?

Other question is. If I have lot of characteristcs to measure defined in control plan, do I need to measure all of them?

Thanks in avance?]]>

We want to qualify a new internal Lab based on our Global methods.

From my understanding, what I need is not a Gage R&R, but rather a Method R&R:

3 labs measuring 5 samples for 2 times (following the same global method)

Even if the global method is the same, the equipments and work instruction in the different Labs are not the same.

Should I consider this like a standard Gage R&R? I assume we will get %SV/Tol higher than the acceptable 30%, since the gages are not...

R&R Study for labs, not for gage]]>

But how we can define CLOSE limit while sample selection.

What is the exact value of closed limit.

Thanks in advance for your valuable support.]]>

Calculating K1, K2, and K3 for 30 part sample]]>

- What would be the best practice for doing an MSA on the torque Wrenches?
- How do you determine the "machine error" over time, as torque is represented as revelations?
- How would one make sure that the torque is still correct when process is completed. (sanity...

MSA on Torque wrench]]>

So in the MSA section the requirement is to use Control Limits and not specification limits on the MSA before SOP. To my knowledge Conrol limits are calculated by CL=m + or - 3*std deviation?

What global is saying, is we must redo the study but use Historical Standard deviation from our SPC done with line side data collection.

So when we redo the MSA using the same...

Difference between Control Limits and Historical Deviation]]>

I am a rookie in MSA. I just run few of them (both internal and for customers) but I still have some doubts regarding the correct way to run a Gage R&R when we have a tolerance given by our customers, and I hope you can help me to dissolve these doubts.

Here below two approaches to run a MSA:

1) Sample selection: samples taken on purpose over the entire tolerance field given by customer.

--> We consider the

Gage R&R according to customer spec]]>

Let me preface this with I am not six sigma certified.

I recently got a new job where we use a balance to measure the contamination on a tin. The general process is as follows:

- weigh tin
- add solvent w/ contaminate to tin
- evaporate solvent; leaving contaminate behind
- weigh tin again
- delta in weight is the weight of contaminate

Gage R&R - Uncertainty in Contamination]]>

First of all, I hope you and your families are all safe and healthy in these pandemic times.

I have a question about the Repeatability & Bias MSA (Type 1), maybe you can enlighten me:

Generally for Type one study we need to measure 30 time the same sample.

How it work with destructive tests? Should we only assess the Bias by measuring 30 different reference samples? What do you do generally? Any experience to share?

Any help is welcome

Samuele]]>

Performance to Tolerance (P/T) ratio uses σ_R&R / (USL - LSL) as an estimate of a gauge capability while GRR method uses σ_R&R / σ_total where σ_total is given by...

P/T ratio vs GRR - which is more meaningful and why?]]>

Quick question:

Theoretically, if for a MSA all the samples will be measured by the operators only once, we should not have information about the repeatability, right?

Why also Minitab give me varcomp and all the other information about repeatability?

thanks in advance.

Samuele]]>

Gauge R&R or just R?]]>

We ask for MSA's / PPAP's of our suppliers because our own customers insist on receiving the files for their administration. I have a fourth edition MSA book, but i'm hesitant to simply follow up on the information in the book.

Can someone explain to me what key factors are the most important when it comes to judging a supplier's MSA?

See the picture below, which we could use as an example.

View attachment 723]]>

GR&R gauge readings]]>