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True Position of holes, without Diameter symbol in Control Box??

let me lay this out for you guys and gals the best I can:

I have Datum A wich is a inside Circle recessed into the top of the part. We will call this "Datum A"

I have another recessed circle on the bottom of the part. We will call this "Hole"

"Hole" has a dimension callout that reads as follows: Dia. 7.06"
[T.P./.010/A] Notice there's no Dia. Symbol in the Cntrl Frame

I have never seen this callout before without the Dia. Symbol in the control frame when in reference to a datum that is a circle or cylinder, have you?

If I run this with both features as Circles, I get a measurment of 0 (ZERO)

If I run this with both features as Cylinders, I get some actual numbers, but I don't know if they are correct.

If I run this with Datum A as a Cylinder and Hole as a Circle, I get 0(ZERO)

I am confused as to which way i am supposed to do this. Is the callout on the drawing messed up, or am I giving Pcdemon incorrect features to calc this dimension?

Any help would be greatly appreciated.

Sam
Parents
  • with a touch probe the CMM is never truly measuring the entire length of a feature. Even with a scanning probe if that feature is not a thru hole you can't probe it right up to the surface it intersects.


    Just wanted to point out that pcdmis evaluates the position of a cylinder over its defined length, regardless of where you take the probings. So as long as you've defined the cylinder to cover the entire length of the feature, it will be evaluated over the entire length. This can be good and bad (mostly good), but its important to know.
Reply
  • with a touch probe the CMM is never truly measuring the entire length of a feature. Even with a scanning probe if that feature is not a thru hole you can't probe it right up to the surface it intersects.


    Just wanted to point out that pcdmis evaluates the position of a cylinder over its defined length, regardless of where you take the probings. So as long as you've defined the cylinder to cover the entire length of the feature, it will be evaluated over the entire length. This can be good and bad (mostly good), but its important to know.
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