I am having trouble programming my first profile, could use an assist.

[[Mi...]]

I have uploaded an image of the relevant print information, and I wanted to include what I have programmed so far, but can't seem to upload the CMM file.

I choose profile, select the toleranced plane as the feature, Datum -A- as primary, and Datum -B- as Secondary,  .008 bilateral - one result. At the end of the run, the profile is the only thing that comes up purple with an error that says "Evaluation of Characteristic not possible". I'm not sure if it's something in my alignment, or points taken, or poor understanding of profile, I'm just not sure what is going wrong.

I wish I could include more information at this time, so if there is any other information needed from me just let me know and I'll try to find it.

 

Thank you for any help.

[[Ma...]]

I think your profile should be only for upper plane.

This datum A is not drawn correctly - is your datum A an inner cylinder?

If you post screenshots with a setup of that profile callout ( just that window with datums and feature ) it would be helpfull too.
Here you can post only some of extensions and whole programs are not wise to distribute.

[[DW...]]

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 Add B into the tertiary datum, it should calculate.

[[Mi...]]

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Yes, Datum -A-, is the, poorly drawn in blue pen, .250" Ø cylinder in the center of the part.

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That worked in the characteristic calculating, thank you. Does a profile callout always REQUIRE all 3 datums?

I'm not thrilled with the results I'm seeing, so I reprogrammed in a different orientation, and have only slightly improved my results. Is there any good way of double checking profile manually? I admit I do not have a strong understanding of profile yet, but with my best program, I am seeing .0077" of deviation when my tolerance is .008. So I would think I should see SOME kind of variation even just using basic granites, arbors, and indicators, no?

Example 1 for manually checking: -B- placed against granite table, and running an indicator over the toleranced face, low point to high point across the face is only .0015". "Parallelism to -B-"

Example 2 for manually checking: Holding onto -A- using an inspection arbor and running an indicator along either the toleranced face or datum -B-, .0005" - .001" in deviation.  "Axial Runout to -A-"

Example 3 for manually checking: .250 basic length, .2509 - .2523 across entire face.

Also, the Perpendicularity of -B- to -A- on the print is .00075". Datum -B- plane is evaluated as outer tangential since it is a datum.

 

Are there any other things to check or improve upon? I always struggle to believe and accept what I have taught myself.

 

Thank you again for the help, it is greatly appreciated.

[[DW...]]

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 Yes. Unless you select "No Datum Reference Frame" from the drop down. A surface profile with no DRF is a form only measurement. For example, a surface profile of a plane with no DRF is a measurement of flatness.

To get some visuals and a better understanding of surface profile, click here https://www.gdandtbasics.com/profile-of-a-surface/

Also it is important to understand the different evaluations when using surface profile. The standard tolerance zone is bilateral - one result. This means you have a tolerance zone equidistant from the nominal contour of your part, and the tolerance reported is the largest deviation doubled. This will always be a positive number, which may not always be helpful when troubleshooting a surface condition. A bilateral tolerance zone with two results will give you the minimum and maximum deviations from the nominal surface. This may be more helpful when troubleshooting a surface condition. 

The plane with the surface profile call out must fall within a bilateral tolerance zone of 0.008 inches with respect to datum reference frame AB. Datum A is the inside diameter cylinder axis and datum B is the large plane parallel and 0.250 inches from the measured plane. By using the surface profile call out, the engineers want to control the location, orientation, and form of the plane with respect to the perpendicular created by DRF AB. 

If you were to add up the deviations you measured using granite and hand tools, and doubling them, would you be close to 0.0077?

 

Edited 5 hours ago