• If you have provided a Tolerance Interval in the Enter/Verify Gauge R&R Specifications window, a % of Tolerance column appears in the Gauge R&R report. This column is computed as 100*(Variation/Tolerance). Also, a Precision-to-Toleranceratio appears at the bottom of the report. This ratio represents the proportion of the tolerance or capability interval that is lost due to gauge variability.
• If you have provided a Historical Sigma in the Enter/Verify Gauge R&R Specifications window, a % Process column appears in the Gauge R&R report. This column is defined as follows: 100*(Variation/(K*Historical Sigma)).
• The Number of Distinct Categories (NDC) is defined as (1.41*(PV/RR)), rounded down to the nearest integer.
Below are my results. If I use the 3.4% Gauge R&R then I believe my MSA is Excellant.
But if I look at the .81 Precision to Tolerance Ratio my MSA is not good as I would read this as 81%. Which is the correct number to use for the above guidelines?
Gauge R&R (copied as Text)
Measurement Source Variation (6*StdDev) % of Tolerance which is 6*sqrt of Repeatability (EV) 0.0779517 77.95 Equipment Variation V(Within) Reproducibility (AV) 0.0221650 22.17 Appraiser Variation V(Technician) Technician 0.0221650 22.17 V(Technician) Gauge R&R (RR) 0.0810417 81.04 Measurement Variation V(Within) + V(Technician) Part Variation (PV) 2.3527216 2352.7 Part Variation V(Part SN) Total Variation (TV) 2.3541170 2354.1 Total Variation V(Within) + V(Technician) + V(Part SN)
6 k 3.44255 % Gauge R&R = 100*(RR/TV) 0.03445 Precision to Part Variation = RR/PV 40 Number of Distinct Categories = 1.41(PV/RR) 0.1 Tolerance = USL-LSL 0.81042 Precision/Tolerance Ratio = RR/(USL-LSL)
Using last column 'Part SN' for Part.
Variance Components for Gauge R&R
Component Var Component % of Total Gauge R&R 0.00018244 0.12 Repeatability 0.00016879 0.11 Reproducibility 0.00001365 0.0089 Part-to-Part 0.15375831 99.88 +++++++++