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Need a Gage R&R Range Method Template in Excel?

QI Macros has a range method (short form) template for you.

The Range method provides a "quick approximation" of measurement variability. It will detect unacceptable measurement variation 80% of the time with five samples.

To Conduct a Gage R&R Range Method (Short Form) Study, you will need:

1. five parts that span the distance between the upper and lower spec limits. The parts should represent the actual or expected range of process variation. Rule of thumb: if you're measuring to 0.0001, the range of parts should be 10 times the resolution (e.g., 0.4995 to 0.5005).
2. two appraisers (people who measure the parts)
3. one measurement tool or gage
4. two measurement trials, on each part, by each appraiser
5. a Gage R&R Short Method Template like the QI Macros.

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Example of a Completed Gage R&R Range Method Template

Here is an example of a Short Form Range Method template using data from the AIAG Measurement Systems Analysis Fourth Edition.

How to Interpret Gage R&R System Acceptability

• % R&R<10% - Gage System Okay 
  (Most variation caused by parts, not people or equipment)
• % R&R<30% - May be acceptable based on importance of application and cost of gage or repair
• % R&R>30% - Gage system needs improvement 
  (People and equipment cause over 1/3 of variation)

If the %R&R is greater than 10%, use the long form Gage R&R to determine if it's an appraiser or an equipment issue.

In this example, % R&R is greater than 30% so we should conduct further analysis using more parts and appraisers and the long form.

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