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Profile on diameters


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Profile will control size, location, form, and orientation. Runout will control location, form, and orientation. Any error in size will yield a larger profile deviation than runout.

As far as reporting, the actual numbers are really the only way to convey the error in the part. The only thing that I can think of would be a graphical representation, which you can do in Calypso if you request profile of a line rather than profile of a surface.
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I think your engineer is mistaken. Think about a crankshaft rotating in IC engine, runout is mandatory callout for crankshaft otherwise it would fail in the assembly, runout control dynamic force more specifically centripetal force.
Think about a cam lifting inlet or exhaust valve in this scenario size and profile of the cam is important.Simple words it depends upon the functional requirements when to use runout and profile. Both are not same.
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What strategy recommended for measuring surface profile on diameters. I do not have free form.

What confused the engineer according to report.

What I don't understand is each point are scanned and read the radius are right to the nominal. Where the profile .0026 coming from? I see the blue lines on screenshot are at least .001 range but according to Radius measurement on each point looks fine.

Profile issue.pdf

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Think of profile as deviation from nominal SURFACE . You are reporting profile as a single number. In that case calculated as worst x 2.. You can report profile with two results for more information. It will then be a 1:1 relationship.

A perfectly round diameter, perfectly centered would still fail profile if size deviated from nominal SURFACE.
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Profile characteristic has a drop down list:

Bilateral-one result
Bilateral with unequal distribution-one result
unilateral(inside)
unilateral(outside)
Bilateral-two results
Bilateral with unequal distribution-two results
outwards to infinity
inwards to infinity
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Keep in mind that profile unless otherwise stated, is equally disposed about nominal geometry. Your .002" tolerance is actually .001" PER SIDE. Bilateral with two results will show one (the worst) deviation as 1/2 of your .0026 result. So one (inside or outside) will be .0013" which still violates the .001" PER SIDE tolerance. It will not make the result good
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One more suggestion and I'll let this die.

It is sometimes helpful to report the components of error. So in the simple case of runout requirement. You can report runout, but that does little in the way of communicating the condition of the part. It does not provide actionable data to troubleshoot or correct the problem. So you could also include cylindricity or roundness of each feature(datum and measured). Additionally you can report position. Position will also give you clues to vector as it is the worst case along a cylinder. With the supporting data you can decide the degree each is contributing to the total error. Form, Position, Vector
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Here is a GD&T Reference Guide as it relates to ASME Y14.5-2009.
Usually when I question the engineers application on a print I will show them this and generally will get no argument when they have to correct their call out.
Hope this is helpful

Greg Kozera
333_62c98db1b7208ef52d61fe1b8e60e9f1.pdf
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