2 point diameter/ max inscribed. I need some explanation.

[[Da...]]

Just a bit of background first. We are a precision grinding service job shop. So we work on other peoples parts and finish the high precision surfaces that are out of reach to most machine shops. We are a sub contractor. Our customer doesn't know how to answer me, and is reluctant to go to the end user to clarify what I am questioning. The print shows a LP ( two point diameter) and a GX ( max inscribed association criterion). LP produces 2 diameter readings (Max/min), And GX will produce a different diameter due to roundness variations. Not shown in the picture is a concentricity call out of .0008 with a Max material modifier. I know that GX will produce a center for the circle , but does LP produce a different center ? should LP be used only for size, and GX only for concentricity? How do I use these both at the same time?

[[Ma...]]

LP simulates caliper measurement. So opposing points would be your result.

I would use (E) nad LP on drawing - not sure why mix both methods. Or just report both values.

[[Da...]]

Martin, What do you mean "(E)" ?

And LP (2 point diameter) is an option in the "size" Standards" pull down. It produces a max and a min Diameter.

[[Ma...]]

By (E) it's meant envelope - it's often used with LP - so LP will give you MIN and (E) will give you something like GX ( on shaft )

It's on that Two point diameter characteristic - you can enable there (E) ( by those brackets i mean circle )

[[Je...]]

Dave,
(E) is the Envelope condition, that you can set at 2 Point Diameter. It Gives you (at OD) the GX for the upper tolerance and the lower LP for the lower tolerance - so, just what you need, I guess (I know, in ISO it would be what you need based on your drawing).
For concentricity: I don´t know for ASME, but in ISO the concentricity-callout is defined as LSQ-feature, and as OTE (GX/GN) for the datum

Edited February 11

[[na...]]

Is tolerated diameter a hole or a pin?

If it's a hole, combination in the drawing is very strange, normally designer would want (E) as Martin says.

But envelope on the hole will control the smallest tangential feature with the lower limit (.3150 in your case), and the biggest 2-point distance with upper limit (.3156 in your case).

So switched symbols on lower and upper limits.

Edited February 12
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