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Pass fail to tolerances

Here is my problem. If I say I only want to report 3 digits and .005+/-.001 and the result is .0061 it will show me a fail. I want it to show me a pass. Same with .0039 want to show as a pass.

Anything in the software that I can turn on to correct the pass fail with that?

Any thoughts would helpful can think of some work arounds.

  • Then there are those of us with 0 position tolerance try to get the shop to remove as much as possible to make the parts easier to pass.
  • That's a terrible practice and effort should be made to curb it. If you have a -.001 tolerance and want a deviation of -.00149 to show as passed, you basically just gave it an extra 49% tolerance. My compromise after repeated discussions was to report 1 decimal place more than the print. Even with that, every time we get a new manufacturing supervisor or manager (even a QE one time!!), this issue is brought up again.
  • CMM = Characterization Magic Manipulation ?????
    Even if I think it's a very bad idea to accept OOT parts without a real customer acceptance, you can easily change the tol to 0.00549/-0.00149 with 3 decimal places, it should be invisible on the report numbers, but a part with a 0.005 deviation won't appear with a total graphic deviation...
    It's a kind of magic, it's not metrology !!!!!
  • If he's got an SOP that states thout shall round for all drawings, and this SOP is accepted by their customer(s), then thout shall round per that SOP!
    --The only exception is when it comes to conducting a gage study (MSA). You should never apply rounding to a gage study.

    FYI, you can actually further obscure (or control) the dim tolerances by making the tolerances on each dim point to an assignment variable.

    Here's a truncated segment of a routine I made that parametrically shifted tolerances so any time we run the routine with a "qualification" toggle, it refers to the GAGERR dim values

    IF/GAGERR == 0
    $$ YES,
    DRAWING SPEC GRAY OUTER BODY
    ASSIGN/TOL_AA_P=0.005
    ASSIGN/TOL_AA_M=0.02

    END_IF/
    ELSE/
    $$ YES,
    GREEN SPEC GRAY OUTER BODY
    ASSIGN/TOL_AA_P=0.01
    ASSIGN/TOL_AA_M=0.02
    END_ELSE/
    END_ELSE/​

    DIM AA_GATE_1= 2D DISTANCE FROM PLANE APLANE_1 TO POINT AD_GATE_1 PAR TO YAXIS,NO_RADIUS UNITS=IN,$
    GRAPH=OFF TEXT=OFF MULT=10.00 OUTPUT=BOTH
    AX NOMINAL +TOL -TOL MEAS DEV OUTTOL
    M 5.378+0 TOL_AA_P TOL_AA_M 5.37762 -0.00038 0.00000 --#-​
  • ooh there's an extra else as there were two part variants (resin type/color). I have unique dims for color 'A' and a second set of unique tolerances for the gray in the above code.
  • Here is my problem. If I say I only want to report 3 digits and .005+/-.001 and the result is .0061 it will show me a fail. I want it to show me a pass. Same with .0039 want to show as a pass.

    Anything in the software that I can turn on to correct the pass fail with that?

    Any thoughts would helpful can think of some work arounds.



    Sorry Peter .0061 is out of tolerance.
  • What you want to achieve is in direct violation of ASME Y14.5 Section 2.4 (this is from ASME Y14.5-2009)

  • What you want to achieve is in direct violation of ASME Y14.5 Section 2.4 (this is from ASME Y14.5-2009)

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    “Only a Sith deals in absolutes.”
  • Some agencies actually specify what he is looking for.
  • What you want to achieve is in direct violation of ASME Y14.5 Section 2.4 (this is from ASME Y14.5-2009)

    {"data-align":"none","data-size":"full","title":"image.png","data-attachmentid":530779}


    see what Mike Ruff posted...