That said, I agree 10,000% with Miner that having the operators measure different parts is NOT an MSA. In MSA you need to be able to separate the contribution of 3 factors (or components of variation):

(1) the ability of the measurement system to measure the same value of the same location on the same part. This is repeatability variation. So each operator must measure the same place on the same part at least 2 times. This creates a crossed study. If the measurement is non-replicable as in many profilometers or is destruct then you must use a nested study design. Both Miner and I cover this distinction in our posted papers in the resources section.

(2) the ability of different operators to measure the same location/part and get the same value as every other operator. This is Reproducibility; operator to operator variation.

(3) the contribution of the part variation itself. Sometimes this includes within part variation as well.

**Is the profilometer a contact or non-contact instrument. This really, really matters.**I have worked with both. A non-contact one can in fact measure the exact same location on a part multiple times and will allow you to perform a crossed study. If it is a contact instrument then you are stuck with a nested design. Then you will need to program the thing to measure specific not random locations.

A proper study design will allow for the math to separate and quantify the contribution of these 3 factors.

No offense but it seems that your advanced knowledge of statistical calculations (MS) has not prepared you for understanding the mechanics of statistical study designs. This is not uncommon by the way. No engineering or scientific discipline prepares the graduate for the real world application of their discipline. The graduate needs mentoring and coaching in the real world.