TP of a Tab

[ag162]

Good Morning,
I have a simple question:
On my print, there is a TP callout for a tab width. How is this dimensioned?
In the FCF there is the TP symbol, 1.5M, To Dat A, B, C. The leaders or arrows are pointing ot both sides of the rectangular shaped tab.


Thanks in Advance,
A.Gore

[george frick]

from your description without seeing the print this appears to be a unilateral true position callout. measure the tab in relation to the basic dim in one direction (axis). report this and include mmc for the size of the tab. that should do it.

[Mike N.]

I would view that as the centerline with the bonus of the width deviation

[george frick]

tru-pos

I would view that as the centerline with the bonus of the width deviation

exactly!

[tking]

I concur with George

TK

[Rich P]

I would consider it as possibly treating this as a symmetry

[tking]

Rich,

The position callout is used to allow for MMC application. If my old gray head recalls correctly, symmetry doesn't include material modifiers in the FCF.

It's been a while since I read anything on this so if I'm wrong (again) have some mercy, folks

TK

[Perry Fisher]

I see this often in the parts we run. From reading posts from Matt, John Boy and others I create a generic circle using each side of the tab. This puts the circle CL on the tab CL. Then dimension the True Position of the generic circle giving me the MMC of the tab. This has always worked for me.

[kbotta]

Alton,
This would control the axis, or median plane. It is called a bi-directional positon, not unilateral. It is not symmetry. Symmetry controls the median "point cloud" (see 14.5).
I'd construct a middle plane, and dimension it as TP. You didn't shown any msterial condition modifier's - so I would ASSume rfs....
Hope this helps,
Kev