True Position of a notch to an OD

[parrottk]

I created a notch using auto feature .059 x .140 true position callout is
.059 +- .0005
[.002][B,max]
-B- is the outside diameter of the part.
the notch is located on the Y c'line and .0295 on each side.
hits are showing X-.0312, X+.0285 location is off?
true position reads perfect 0.000000
part is aligned to the face Z+ leveled to face
rotated to the notch Y+
origen to Z face X,Y to -B-

thanks

[kbotta]

....

[Paul Sarrach]

did you true pos the X Axis? If I understand you correctly, the surface is Z zero, the center of the part is X Zero, and you rotated the X Axis to the notch center, then I would use the distance function for your true position. You are trying to dimension the face of the notch not the sides. correct

[parrottk]

NOTCH IS ROTATED TO Y+
TRUE POSITIONED THE X AXIS

[J Temmen]

If you rotate the +Y axis line through the notch then the X axis will be zero on the features used. Just like a fixture plate, when you measure a +Y line and rotate to it you then set the X origin on it as well.

[JIM HARRIS]

If you are using datums with mmc it may be .0000 true pos. pc-dmis uses a fitter. for mmc.Datums and features can rotate and shift within there tol.Turn mmc off to rfs then you should see your dev.

[Paul Sarrach]

can you scan and down load that?

[cmmguy]

What controls the rotationaly alignment about the Datum B.

btw...
Why is your cylinder not your primary axis and the face secondary. I don't understand why you aren't leveling on the cylinder. esp when the notch is called out to -B-

[kbotta]

It always helps when someone can post a drawing....

[Paul Sarrach]

kev, your right. Guessing is not really helping, now is it. lol What we need is details,details,details...........................

[kbotta]

It would be nice if whenever anyone had a question about position, datums, drawings etc... they would post a pic - or portion of - the drawing. it helps, and yes Paul - keeps from guessing!
There is a lot of info right here! You just have to make sure get the right info.
Kev

[bboyd]

Done a lot of parts with a similar single notch called out to the Dia. Eng is looking for the to faces of the notch to be parallel to each other and perpendicular to your axis. Sometimes I think they pick TP because it was the only one anyone ever told them about in school

[Paul Sarrach]

boyd, can you download a pic?