Is there any reason two coaxial holes with a composite positional tolerance can't be used as a Datum? To be clear, the holes are located to a DRF with one tolerance and tighter to each other with another in the composite FCF. With these two coaxial holes established, a second DFR will be...
Please advise.
The attachment shows three callouts of a surface profile.
The top picture is simple enough. A bi-lateral tolerance with the limited length is called out with a center line (one small lines between longer lines, reference Figure 1.1 of 1994).
The middle picture depicts a...
When using datum targets on a flexible part with a complex shape, there is no limit to the number of primary target points. Can the secondary have more than two target points?
I have an Assembly that has both a ridged, relatively small part and a larger, flexible part each bolted and riveted together thru a series of other parts. In regards to selection of a datum scheme, the primary datum could be a feature on either of the parts as they both equally represent...
I have part with complex surface with 4 target points for primary and 4 edges, no two opposing edges.
I want to use two target points on each of two opposite, but non-opposing edges to create a compound secondary datum to use as a center plane. Is this acceptable?
Unless I am missing it, multi single segment profiles are not mentioned in 1994. Supplemental books of 1994 standard do discuss it, but they are but clear to me. I need to understand refinement of upper segment edge profiles. I think for both composite and multi single segment profiles it is...
I have seen some drawings for parts that have surface profile call outs of a lofted surface. The FCFs have profiles with no Datum references in the FCFs. It has been suggested that the datum references in the FCF of the profile are not required since, for surface profile of .020, the surface...
I see a lot of parts with surfaces that have complex curvatures. Drawings(only) define the parts and those complex part surface features. Many drawings have hole locations in the part defined with point tables (with 3 place X,Y,Z coordinates). The drawings have no datums, no tolerances and no...
