Circular Runout applied to a cylindrical surface defined with basic dims and profile control

[dtmbiz]

Yea's and nay's ?

A diametrical contour is rotated about an axis and is defined with basic dimensions and a geometric Profile control.

Is applying a Circular Runout control to one or more of the contour's cylindrical surfaces which are defined with basic dimensions
(vs. "limits of size"), in compliance with ASME y14.5 1994 ?

 

[tim_member]

Are you asking about a scenario similar to Fig. 6-17 in '94?

 

[dtmbiz]

Yes Tim that is exactly what I was looking for. Thank you

 

[greenimi]

Interesting enough runout could be used with ± and with basic dimension angle.
Not sure myself why the standard is allowing both......

 

[dtmbiz]

Greenimi
That was the question here on site as to whether or not a basic dimension with a profile control qualifies as a
limit of size dimension. By definition profile control does include size.

In years past I wanted to use a basic dimension (the length of a rectangle) as a feature of size datum feature.
Most every one was opposed, siting that it was not associated to a size dimension.

The circular Runout control text does not state whether or not the control requires a dimension with a local tolerance (or default tol.), or basic dimension.
It does have a note under two figures (6-47 & 6-48) that say it must fall within the limits of size.

If you look for the definition for limits of size (1.3.27) you will find "The specified maximum and minimum sizes".

Most of the time in my experience Circular and Total Runout are applied to features defined with a local tolerance (or default to gen tol.)
And then comes the figure 6-17 with Circular Runout applied to a profile defined with basic dimensions.

Unfortunately that example is in the Profile section and not in the Runout section.

Posted the question because I wanted some other feedback to consider

 

[chez311]

dtmbiz,

I know it might not be of help since you referenced Y14.5-1994 but in Y14.5-2009 there is an example of a FOS associated with a basic dimension specified as a datum feature.

Unfortunately that example is in the Profile section and not in the Runout section

I don't think that makes it any less valid as supporting that circular runout can be used in conjunction with basic dimensions/profile.

 

[greenimi]

And in 2018 version of Y14.5, dimension 80 (datum feature C) has been changed to basic (without changing the concept).

 

[dtmbiz]

Chez311 & greenimi
Yes I have seen that in the later standards there has been this update.
Too bad we are on 1994
Good that the ASME update was made in later versions
Thank you

 

[pylfrm]

Is applying a Circular Runout control to one or more of the contour's cylindrical surfaces which are defined with basic dimensions
(vs. "limits of size"), in compliance with ASME y14.5 1994 ?

I rarely care whether a drawing complies with the requirements of ASME Y14.5. Usually it's much more important that the tolerances on the drawing have well-defined meanings. Is your situation different?

There is nothing in ASME Y14.5M-1994 section 6.7 that prohibits what you propose. If the meaning of the tolerance is defined and the usage is not specifically prohibited, then there is no problem.

In years past I wanted to use a basic dimension (the length of a rectangle) as a feature of size datum feature.
Most every one was opposed, siting that it was not associated to a size dimension.

It seems you were correct:

The datum feature symbol is applied to the concerned feature surface outline, extension line, dimension line, or feature control frame as follows:
...
(b) placed on an extension of the dimension line of a feature of size when the datum is the axis or center plane.

Feature of Size. One cylindrical or spherical surface, or a set of two opposed elements or opposed parallel surfaces, associated with a size dimension.

With profile tolerancing, the true profile may be defined by basic radii, basic angular dimensions, basic coordinate dimensions, basic size dimensions, undimensioned drawings, or formulas.

pylfrm