Specifying the location for a CMM

[ryandias]

I have been asked to specify the location of the CMM prob "touches" to reduce the variation due to non-consistant location/"touches" (IE Draft of plastic piece).

I am still a bit unsure how to really specify this. They gave me an X & Y coordinate in one view. Now how do I make this a "dimension?" Is there a specific GD&T symbol?

I was looking over a book, and the best i could relate to is a Datum Target Area. but i'm not terribly sure this is exactly what I need?

 

[JohnNabors]

Ryandias-

I would specify it in the drawing notes and then use flagnote symbols with reference dimensions to indicate the locations of the points to be probed.




John Nabors

"Against stupidity the very gods themselves contend in vain." - Friedrich von Schiller

 

[dingy2]

One cannot use datum targets since we are not setting up on a datum but reflecting the exact point on a surface where we will be taking the dimension.

I would probably reflect the contact points using phantom lines from the datums and basic dimensions. The contact points could be called a letter of some sort and the measuring information could be noted on the drawing.

Dave D.

http://www.qmsi.ca