Can you use true position on planar feature of size? 1

[roywu2002]

Can you use true position on planar feature of size? If so, please give me an example!

Thank you very much!

 

[KENAT]

What standard are you working to and what do you mean by 'planar feature of size'?

Position can be used on slots/key-ways and on the male equivalent (tabs/keys) etc.

While holes are it's primary use that is just the tip of the proverbial iceburg.

Posting guidelines faq731-376

http://eng-tips.com/market.cfm?

(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​

 

[fsincox]

I am not sure what you mean here, I was thinking, like the centerplane of a keyway may be a planar feature of size?

 

[CheckerHater]

Position is used on features like obround slots, but more complicated shapes usually require profile as well.
Is that what you are asking?

 

[SeasonLee]

Roy

True position is the theoretically exact location of a feature of size defined by basic dimension. A tolerance of position (TOP) control is a geometric tolerance that defines the location of a FOS from its true position, like hole or shaft TOP always require basic dimension to define their location.

As for planar FOS, here is an example of true position to define the tab location, but this a special application of applying only one basic dimension, this will control the location and orientation of the center plane relative to datum A.

SeasonLee

 

[roywu2002]

SeasonLee:

That's exactly what I was asking for. That was very helpful. Your post led me to look up TOP. I'm an entry mechanical engineer so I still have a lot to learn. Thank you so much! Really appreciate your help.

Roy