Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations SDETERS on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Is Datum B understood to be a centerline?

Status
Not open for further replies.

Barnon

Mechanical
Jul 23, 2016
97
I'm trying to reference Datum B which is the centerline of a cylindrical surface originating on a previous sheet. I see examples similar to this where the Datum is actually the 33.57 dimension (see example at bottom).

DATUM_ytyht4.jpg

datum_2_avocfu.jpg
 
Replies continue below

Recommended for you

In my opinion placing the "DATUM AXIS B" note on the datum axis on another sheet of the drawing is meaningless. The reader still does not know which feature establishes the datum. There could be numerous coaxial features that could be selected as the datum feature. If the note is applied it must direct the reader to the sheet where the datum feature is identified (with the symbol) so there is no doubt which specific feature is the datum feature.



Certified Sr. GD&T Professional
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor