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Profile tolerance

Having a question with a program. My part has a profile callout of .040. The report shows +.020 -.020... And my results say .022, and is RED... I'm not seeing how a profile of .040 is out of tolerance when the result is .022?? Something just doesn't seem right....?
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  • ASME14.5 profile is as follows:
    Condition 1: If all point are positive error the reported value is: Nominal "0" to your worst positive error. Example(profile of .04 AKA +.02-+.02) no negative error... worst positive error of 0.022 will result in a failing profile of .022
    Condition 2: If all point are negative error the reported value is: Nominal "0" to your worst negative error. Example(profile of .04 AKA +.02-+.02) no positive error... worst negative error of 0.022 will result in a failing profile of .022
    Condition 3: Error is both positive and negative: reports the difference between the largest negative and highest positive. Example(profile of .04 AKA +.02-+.02) 0.002 worst negative error... worst positive error of 0.019 will result in a passing profile of .021

    Only ISO GPS is 2x the worst error
  • Just to elaborate - the actual value for profile is defined (in ASME Y14.5.1-1994) as two values, namely the largest deviation external to nominal and the largest deviation internal to nominal. The new revision of ASME Y14.5.1, 2019, redefines the actual value of profile as essentially twice the largest deviation from nominal. The technical details are included in Y14.5.1-2019, and I'd encourage you to investigate if you haven't already.

    Up until PC-DMIS 2020 R2, with the introduction of the Geometric Tolerance command, PC-DMIS had made it's own rules for displaying a measured value when choosing ASME Y14.5. Those rules are the three conditions that you've stated above. After, and including, 2020 R2, PC-DMIS displays the measured value as twice the worst deviation from nominal when choosing ASME Y14.5 or ISO 1101.
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  • Just to elaborate - the actual value for profile is defined (in ASME Y14.5.1-1994) as two values, namely the largest deviation external to nominal and the largest deviation internal to nominal. The new revision of ASME Y14.5.1, 2019, redefines the actual value of profile as essentially twice the largest deviation from nominal. The technical details are included in Y14.5.1-2019, and I'd encourage you to investigate if you haven't already.

    Up until PC-DMIS 2020 R2, with the introduction of the Geometric Tolerance command, PC-DMIS had made it's own rules for displaying a measured value when choosing ASME Y14.5. Those rules are the three conditions that you've stated above. After, and including, 2020 R2, PC-DMIS displays the measured value as twice the worst deviation from nominal when choosing ASME Y14.5 or ISO 1101.
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