Tangent Plane Modifier 4

[weavedreamer]

The intent is to control the extrusion of a spherically tipped rod back to two mounting holes.
This is the proposed solution.

 

[weavedreamer]

May the tangency plane modifier be legitimately invoked as illustrated?

 

[CheckerHater]

I don't see the problem here.

You have curved (domed) feature so you control it with Profile.

The only thing that is (functionally) important is the contact with tangent mating part, so you use tangent modifier.

Using two round holes as RMB datum features may be not convenient, but still legal.

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 

[powerhound]

No. You cannot use the tangent plane modifier on anything but nomially flat surfaces.

John Acosta, GDTP Senior Level
Manufacturing Engineering Tech
SSG, U.S. Army
Taji, Iraq OIF II

 

[weavedreamer]

Can the profile apply just to the height, and just drop the modifier, John?

 

[powerhound]

Yes but you need to make the radius a basic dimension. The profile is applied to the surface of the radius, not to the height dimension.

John Acosta, GDTP Senior Level
Manufacturing Engineering Tech
SSG, U.S. Army
Taji, Iraq OIF II

 

[weavedreamer]

By changing the radius to basic, and using the profile, isn't that requesting the radius to be checked too?

All that is really desired at this level in the assembly is to check the protrusion relative to the mounting scheme.

 

[CheckerHater]

You cannot use the tangent plane modifier on anything but nomially flat surfaces

Reference, please...?

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 

[powerhound]

ASME Y14.5-2009

John Acosta, GDTP Senior Level
Manufacturing Engineering Tech
SSG, U.S. Army
Taji, Iraq OIF II

 

[CheckerHater]

Paragraph?

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 

[powerhound]

Can you really not look it up yourself?

John Acosta, GDTP Senior Level
Manufacturing Engineering Tech
SSG, U.S. Army
Taji, Iraq OIF II

 

[pmarc]

CH,
One question or two actually. Assuming for a moment that you are allowed to apply tangent plane here, what is the length of that plane and how does the tolerance zone look like?

 

[CheckerHater]

Can you really not look it up yourself?

Looking...

Definition (from Para. 1.3.45)

plane, tangent: a plane that contacts the high points of the specified feature surface.

No mention of nominally flat surface.

Application (from Para. 6.5)

...The tangent plane symbol is illustrated with orientation tolerances; however, it may also have applications using other geometric characteristic symbols where the feature is related to a datum(s).

Interesting... The OTHER symbols using datums(s) are position, concentricity, symmetry, runout and profile.

Still, couldn't find where exactly use of tangent is limited to flat surfaces.

Anybody?


"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 

[CheckerHater]

@pmarc: what the length of tangent plane has to do with anything?


"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 

[powerhound]

You left a lot out of your condensed version of 6.5. It does mention that flatness is not controlled when a Tangent plane is specified. This would imply a nominally flat plane. If it applied to any type of surface then it would have said that FORM is not controlled by the geometric tolerance. It also says that the tangent plane would contact the high pointS of the surface.

Since you seem to think that Tangent plane can be used on any characteristic that uses datum references, how would you use it with concentricity?


John Acosta, GDTP Senior Level
Manufacturing Engineering Tech
SSG, U.S. Army
Taji, Iraq OIF II

 

[powerhound]

CH,

Your question to pmarc demonstrates your lack of understanding of the tangent plane modifier.

John Acosta, GDTP Senior Level
Manufacturing Engineering Tech
SSG, U.S. Army
Taji, Iraq OIF II

 

[pmarc]

What if the pin from your drawing was not perfectly perpendicular to the datum plane A (which will most likely be the case in reality)? How would the line depicting plane tangent to the tip look like? How long would it be?

 

[CheckerHater]

powerhound, this is third insult in a row.

What exactly did I do to deserve it?

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 

[CheckerHater]

pmarc,

I lost interest to this discussion. I am sorry.

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 

[pmarc]

What can I say, CH?

I do not know you, but you definitely are not the person who says: "I was wrong" very often.