# How to calculate profile of a surface?

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#### gagegirl

I cannot find any info on how to calculate profile for documentation. I understand the concept but my inspection department is divided on how it is calculated.

Here are some examples of my specific situations...(in inches) [BASICS]
1. [SR .250 BASIC]
[PROFILE OF A SURFACE | .02 | D | E | F] my feature control frame
The radius measures .240. What is my documented profile? Do I need more information to calculate it? Do I need to use centerline basics?

2. all around (flange contour) [PROFILE OF A SURFACE | .04 | D | E | F]
[R .245] 4 PLACES, measures .2435,.2457,.2551,.2403
[R .370], measures .3733
[R .770], measures .7799
[.909] to the centerline of the [R .300] 2 places, .909 measures .9082 radius measures .3010
[.525] to the centerline of the [R .300], .525 measures .5202 radius measures .3105
[R .908], measures .9071
[R .250] 4 PLACES, measures .2479, .2456, .2443, .2521

For example 1 my divided department believes either the answer is a. .010 b. .020 or c. calculate like a position using one centerline basic.
For example 2 my divided department believes either the answer is a. .0198 b. .0396
Sorry for the length but I though by providing examples it may help me get the help my department needs. Thanks.

#### Stijloor

Super Moderator
I cannot find any info on how to calculate profile for documentation. I understand the concept but my inspection department is divided on how it is calculated.

Here are some examples of my specific situations...(in inches) [BASICS]
1. [SR .250 BASIC]
[PROFILE OF A SURFACE | .02 | D | E | F] my feature control frame
The radius measures .240. What is my documented profile? Do I need more information to calculate it? Do I need to use centerline basics?

2. all around (flange contour) [PROFILE OF A SURFACE | .04 | D | E | F]
[R .245] 4 PLACES, measures .2435,.2457,.2551,.2403
[R .370], measures .3733
[R .770], measures .7799
[.909] to the centerline of the [R .300] 2 places, .909 measures .9082 radius measures .3010
[.525] to the centerline of the [R .300], .525 measures .5202 radius measures .3105
[R .908], measures .9071
[R .250] 4 PLACES, measures .2479, .2456, .2443, .2521

For example 1 my divided department believes either the answer is a. .010 b. .020 or c. calculate like a position using one centerline basic.
For example 2 my divided department believes either the answer is a. .0198 b. .0396
Sorry for the length but I though by providing examples it may help me get the help my department needs. Thanks.

Any chance you can attach the actual drawing? Or portions of it? I may be able to help, but without a drawing, I have to assume a few thing which I do not like. Keep in mind that the basic dimensions specify the location of the profile tolerance boundary. A profile may be dimensionally correct, but if it is not located correctly, you still have a nonconforming part. To answer your questions correctly, I would need to know if the tolerance boundary is equally disposed about true profile. See? So a drawing would help.

Stijloor.