multiple Basic Dimensions vs reference

[charles_billingsley]

I am looking for the clarification regarding multiple basic dimensions, I have been told you can have multiple 'basic" dimensions shown throughout a drawing of the same feature. e.g. a hole .500 off an edge, I happen to show this basic dimension .500 on multiple sheets, versus having it one time basic and all the others REF dims.

[Kelly_Bramble]

The applicable rule within ASME standard is:

"Each necessary dimension of an end product shall be shown or defined by model data. No more dimensions than those necessary for complete definition shall be given. The use of reference dimensions on a drawing should be minimized."

This rule is mostly interpreted as one placing only one limit or basic dimension on an engineering drawing - achieve "necessary for complete definition"

ASME Y14.5-2018, 4.1 Fundamental Rules, page 12

It has been my practice and that of many to only show a dimension once whether it is a Limit or Basic dimension so as to avoid the possibility of conflicting dimensions due to misplacement.

Additionally, showing a dimension once is less work, more efficient and result in a better organized engineering drawing.

[charles_billingsley]

Thank you for the reply, and yes I know all what you stated and agree however that did not answer my question, which I know sounds silly. If you "happen" to have a basic dimension and that same dimension is shown multiple places, does it remain basic or should it be in () indicating REF.

[Kelly_Bramble]

Thank you for the reply, and yes I know all what you stated and agree however that did not answer my question, which I know sounds silly. If you "happen" to have a basic dimension and that same dimension is shown multiple places, does it remain basic or should it be in () indicating REF.

Yes, however you did indicate "I happen to show this basic dimension .500 on multiple sheets,"

I would recommend you duplicate dimensions as (reference) and only if it is helpful to the engineering, design, manufacturing or quality intent.

Back to my original response/post - last sentence.

"Each necessary dimension of an end product shall be shown or defined by model data. No more dimensions than those necessary for complete definition shall be given. The use of reference dimensions on a drawing should be minimized."