reporting MAX(GX) MIN(GN)

[programmer]

i am trying to report MAX(GX) MIN(GN). Can someone tell me if I am using the function right? See attached. I am measuring the circle under LSQ. Report it using GX, GN and Diameter of location of circle and getting different results. Capture.PNG

[bfire85]

You gave GX for both upper and lower. Use GG to report least squared. GX is Max inscribed (used for smallest ID) and GN is Min Circumscribed (used for largest outer diameter).

[programmer]

"You gave GX for both upper and lower." i gave it the +0.001/-0 dimension. Is that the right way of dimensioning it?

[bfire85]

"You gave GX for both upper and lower." i gave it the +0.001/-0 dimension. Is that the right way of dimensioning it?

Not from my understanding. The way the size feature works is you can report, for example, max inscribed and least squared in the same feature. So you enter the nominal size and tolerances like you normally do, but for your upper, you would put GG and for your lower, GX. This way against 0.0632 +0.001/-0, you will have your least squared and max inscribed diameters. You have your definitions messed up on what is what when it comes to reporting max and min diameters. See below for the feature explanations.

From the PC-DMIS help file:

The Size command supports the following modifiers that are defined in the ISO 14405-1 standard:

(LP) - Two-point size

(GG) - Least-squares association criterion

(GX) - Maximum inscribed association criterion

(GN) - Minimum circumscribed association criterion

(CC) - Circumference diameter (calculated size)

(CA) - Area diameter (calculated size)

(CV) - Volume diameter (calculated size)

(SX) - Maximum size

(SN) - Minimum size

(SA) - Average size

(SM) - Median size

(SD) - Mid-range size

(SR) - Range of sizes

(E) - Envelope requirement

ACS - Any cross section or sections

SCS - Specific fixed cross section or sections

[JEFMAN]

Where is OEG ????? LOL

[bfire85]

Hahaha JEFMAN

[programmer]

So when I measure the actual 0.0632 ID do I use Least_SQr or MAX_INSC? The customer wants to see GX and GN reporting for the 0.0632 ID. Can you show an example? I only have the LEAST_SQR in there just to see the difference.

[bfire85]

So when I measure the actual 0.0632 ID do I use Least_SQr or MAX_INSC? The customer wants to see GX and GN reporting for the 0.0632 ID. Can you show an example? I only have the LEAST_SQR in there just to see the difference.

If they specifically want to see GX and GN for an inside diameter (which GN is for an outer diameter anyway) then do something like this:

SIZE4      =SIZE/
            OUTPUT=BOTH, UNITS=MM, STANDARD: ISO 14405-1,
            TOLERANCE SPECIFICATION MODE: NOMINAL_WITH_DEVIATIONS,
            NOMINAL SIZE: 27,
            UPPER TOLERANCE: 0.1,GN,__,
            LOWER TOLERANCE: 0.1,GX,__,
            UPPER SIZE: 27,
            LOWER SIZE: 27,
            FEATURE: A3_2

Otherwise, this would be the best option:

SIZE4      =SIZE/
            OUTPUT=BOTH, UNITS=MM, STANDARD: ISO 14405-1,
            TOLERANCE SPECIFICATION MODE: NOMINAL_WITH_DEVIATIONS,
            NOMINAL SIZE: 27,
            UPPER TOLERANCE: 0.1,SX,__,
            LOWER TOLERANCE: 0.1,SN,__,
            UPPER SIZE: 27,
            LOWER SIZE: 27,
            FEATURE: A3_2

[JEFMAN]

I'm not at the cmm to check, but I think an old bug reappeared : min circ cylinder and max inscr cylinder have the same vector, and the same form defect.
I believe that's a bug which had been fixed long time ago (not sure of it).
If you look at the text values, there are only 4 values at 0 ( I think there should be 5 !).

If someone here can check it, maybe a new thread is needed (I'm off the cmm for a week...)