Help with the GD&T - Tolerance for the Profile of the Surface

[Bigfoot]

I could use some help on this.

The part has two features that have a 0.5mm tolerance for the Profile of the surface. One feature is a stand alone profile on a 7mm deep machined groove for that surface. The other is on the surface of an ellipse that is relative to the 7 mm depth (for an offset) and is tied to datums A - B - C without any modifiers. The engineering dept decided to build a gage using LVDT that provide variable data on the relative position of the machined groove to the top surface more as a position than as a profile. Is this a valid means to check this feature?

 

[Proud Liberal]

If you could send me a scan of the print, I could better advise you on the proposed technique or suggest another method.

[email protected]

 

[Bill Ryan - 2007]

I guess I'm confused when you say the elliptical surface is "relative" to the groove depth (which is not "tied to" any datum?), yet it's "tied to" -A-, -B-, -C- in the feature control frame Does that come from your knowledge of the part fit/function (from your description I don't see the "relativity")?

As with ProudLiberal, I might be of some help if I could see the dwg.

Bill