Profile Datum Structure

[[An...]]

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[[Ri...]]

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That's a maybe. It's hard to get into the mind of the engineer without talking to them.

Issues of measurement discrepancies arise from issues like this where the drawing says this, the standard says this, but the engineer meant this (without conveying that).

To me, unless you have something on the drawing, or a verbal/email from the customer/engineer it is best to follow the standard, so that you at least have a leg to stand on.

In the US, liability is nothing to joke around about because there are people who make an a lot of money ensuring that the blame is put on someone other than themselves.

/rant

[[Er...]]

Woried about consequences ? I have the perfect solution, move to Sweden, here you get promoted if you do wrong. But on the otherhand, why bother work? You get the almost the same money doing nothing...

It's a utopia for everyone, but the Swedes 😃

[[An...]]

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[[Ri...]]

You are correct, the standard doesn't go over every scenario.

Once again, everything that I have read that is generally agreed upon states that you are to follow the can-may-must rule, and that datum order of precedence matters.

My statement is a statement of covering one's rear-end. If you choose to attempt to enter the mind of the designer that is your choice.

[[An...]]

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[[Ri...]]

And every designer is different. Whether that is German, Austrian, American, etc.

I worked in Automotive for nearly 15 years. They are all different, and all interpret things differently.

I wouldn't be as worried about warranty recalls in automotive as I would for something in the aerospace world.

[[An...]]

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[[Ch...]]

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You are looking at wrong standard. Y14.5 doesn't apply to how to measure the part, just design.

1.1.6 Reference to Gaging. This document is
not intended as a gaging standard. Any reference to
gaging is included for explanatory purposes only.


Choosing an alternative way to measure that part that 'meets the needs of the business' is totally acceptable.
ASME B89.7 Measurement Uncertainty

[[An...]]

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[[Ri...]]

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That note has been removed. I believe the intent of that note was to make a statement regarding how a gage should be designed. Probably more of a c-y-a note.

My statement was also more of a sarcastic statement where people get bent out of shape when someone doesn't follow the general interpretation of the standard or general practices.

People can design, and interpret a drawing however they like, and in the case where you are the end user, it doesn't generally matter. Where it matters is the case of you being the supplier. If you do not have direct access to the design engineer, it would be dangerous (depending on the industry) to make your own interpretation. You don't have a leg to stand on other than, "this is how I've always done it".
/end rant