Specifying a datum on a cored hole 1

[SDETERS]

Please see image. We machine some die castings at our location. We have struggled with the proper and consistent way of checking and calling out our Y datum using cored holes on our die castings. (aluminum.)

What we have is a X datum which is defined by three circular datum targets on a face. Then we have a Y and Z datum which are cored holes.

What would be a proper way to call out the Y datum cored hole back to X? Is the way I am showing the Y datum define the entire center axis of the taper core perpendicular back to X? What would be a better way of controlling the perpendicular of the cored hole axis back to X?

We use self tapping bolts in these cores during assembly, so the center axis needs to have a certain perpendicular control back the X datum.

Thanks We are using ASME Y14.5-1994

 

[drawoh]

SDETERS,

The positional tolerance with respect to datum[ ]X has no meaning. You can specify perpendicularity.

--
JHG

 

[SDETERS]

Thanks for this feedback. This helps.

 

[ak762]

Quite difficult to make correct assumption seeing only one section view but the positional tolerance include perpendicularity as well.

 

[SDETERS]

Does the perpendicularity of the hole's axis still apply even though the hole tapered?

 

[ak762]

My interpretation of the definition of the tolerance zone what specified in the frame yes,the perpendicularity of the hole's axis applies though the hole tapered.