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Comparing curve profile to feature radius


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I'm looking for some direction on a problem I have. I have a composite profile that I created with Curve. It contains 2 radii with a line between on either side of a standing nub.. The upper DRF controls position and orientation and the bottom just form. I also have a separate call out for the two radii. I opted not to use the extract from Curve option because the radii are very small (.3 and .55mm) and both less than 45 degrees. So I'm using 3 points with a constraint on x and y.
The radii are often reporting out of tolerance but to look at the unconstrained profile results of the form they appear to be very good.
I'm wondering what I am missing. I read somewhere that you need freeform to accurately report a profile with no DRF but there is an option in the line profile characteristic for "No Datum Reference".
Any advise would be appreciated.

profile no ref frame.pngCallout.pngradius 3 points.png

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Questionable characteristics aside, making a few quick assumptions that I may be wrong about, if you're using the same probe as used in the curve, there's no way you can check a 0.3mm radius with a 0.5mm radius probe and I'd strongly question if it could accurately grab enough points to measure the 0.55 even using constraints.
My guess is the curve is filtering out the radius's in the plot before the curve is best fitted. Might adjust the magnification up to see if there is anything there.
Again, quick reply while eating a hamburger, no sarcasm intended, but, I'll challenge anybody to correct me, I make a mistake or two every year 🤣
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All radiuses are covered by surface profile. All radiuses are have small angle eval - so it's not even mentionable result.
And if you would like to cover this +/- 0,1mm radius by profile, then deviations will be around 0,022mm from center line ( got from solidworks )
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The profiles/ radii are external so they are measurable. I like the idea of the filtering because I've measured small radius's like this in the past with success using the constraints. Your record of being correct stands in my book,. Thanks
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