Measurement system analysis
Can Priya and Noah tell a pass from a fail at 32?
Filled circles are Priya Shah. Open circles are Noah Kim. The line on the first chart is 32 µin Ra. P3 and P4 are the parts whose readings sit on both sides of that line.
How this sheet sits with the others
Priya measures first, then Noah, two trials each. On P3, Priya reads 30 and 32 and Noah reads 34 and 29. On P4, Priya reads 33 and 35 and Noah reads 31 and 36. Those parts change sides of the 32 limit. The readings are the evidence. This sheet does not publish a percent GRR, and it does not show process spread over time.
- What it makes visible
- Priya Shah’s and Noah Kim’s two trials on five parts, against the spec at 32.
- When it is useful
- When a reading near 32 might change sides depending on who measures.
- Who uses it
- Priya Shah, then Noah Kim, the Friday backup on the gage. Noah is not the regular inspector.
- What it takes
- Two trials on each of P1 through P5, in µin Ra.
- What it leaves
- P3 and P4 cross 32 depending on who measures. No percent GRR.
- The underlying record
- Priya Shah's and Noah Kim's readings of the same five parts, and whether each part stays on the same side of 32 µin, are the measurement the capability claim and the bench tally cannot see on their own.
Where these facts go next
What this sheet still leaves out
It has no process spread over time.