True position to holes on not datum surfaces... is this allowed
Hi All,
I have just joined, mainly because I have a GD&T question which I need an expert answer to.
I have a customer component drawing and there are 6 holes on the component with a control frame with datums ABC. The holes are constrained to the 3 datums (two planes and a centre line).
The two plane datums are at 90 degrees to each other and the centre line is perpendicular to one plane, however, the holes are on a non datum surface which is not perpendicular or parallel to the two datum planes. Is this a correct method of geometrical tolerancing? And how would you measure the correct position of the hole if this is correct?
Thanks for any feedback,
Rouge