Duane - FWIW, I have been supplying dimensional reports to the Big 3 as tier 1 and others as tier 2 in the automotive industry for about 12 years now. I also supply our engineering dept with results, when needed. During this time, I have never heard of using the method that you and George describe. I understand exactly what you're describing, but have to agree with Geoff. What good would your method be to an engineer that sees a collection of points probed to verify a certain profile tolerance is met? Let's say that you're checking a surface in one direction only (let's assume -Z) and you find that all the points checked are above the nominal location of the surface. In this case, multiplying by 2 to yield a number that is twice as large as your deviation from nominal won't tell an engineer or toolshop how far and in what direction a surface needs to be moved (corrected) to meet the original profile specification. I've thought about your post for a couple of days now and can't see any good application for the number you arrive at.

Just for reference, I have attached a raw CMM printout which contains the same info that our dimensional inspection reports contain except the final report is made "prettier". We also supply an abbreviated Dimensional Discrepancy Report that summarizes anything OOT.

One thing our CMM doesn't automatically output is vector deviation which I believe is more useful than individual XYZ deviations. I'm working on a way to incorporate that result in our reports, as well.

Looking forward to any/all responses,
Shane

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