Use of tooling balls

[tk369]

Reading some of the posts in this forum, I believe that I've found a great place to ask a question regarding how to dimension a drawing which utilizes a tooling ball.

My companiy's Design Manual tells me to dimension everything to the center of the ball. Yet in my experience, I have always dimensioned "over" the ball, since this is what a CMM would read and could avoid trig errors.

Am I correct in my assumption? Or am I splitting hairs?

Thanks in advance.

ted kralovic

VisVSA, NX-6, Macbook, iPhone 3GS, Garmin 765T, Garmin Forerunner 405, Garmin eTrex Vista Hcx, among others

 

[IRstuff]

I think you should be posting this in the GD&T forum: forum1103. Red flag this and re-post in that forum.

I'm a bit removed from this particular discipline, but there are probably at least two schools of thought on this. There are the purist/idealist that would go for the centers of balls and other inaccessible places, while there are pragmatists that require that all such things be accesible and measurable.

TTFN
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