True position Simultaneous requirement question

[[Ja...]]

Hi, I have tried searching forum for a discussion about this specific question but I could not find it.

I have a part with cylindrical and slot type features in a bolt circle and also with radial features sharing the same DRF: [TP | .010 (M) | A |B(M)] where A is the top plane and B is the ID of the part.

Now doing best fit bore pattern on cylindrical features in the bolt circle is easy enough. But how do you satisfy or if it is needed to plug radial features in the same best fit bore pattern for simultaneous requirement?

Bolt circle features have "diametrical X & Y" shape of zone but radial features need to have their own individual alignment rotated to themselves with "diametrical X & Z" shape of zone and BFBP doesnot allow selection of different shape of zone for individual features.

[[Jo...]]

I think the suggestion before has been using a best fit alignment(from one set) in the second criteria.

[[Mi...]]

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I asked what I believe is the same question. I couldn't get BFBP to work but using a Geometry best fit alignment works fine.

viewtopic.php?p=41885#p41885

[[Ja...]]

That is the post I was looking for, thank you!

But I still have a question. I tried adding radial cylinders (perpendicular to the bolt circle cylinders) to the best fit pattern containing the bolt cylinders to get a BFBP for all features combined and under simulated run the BFBP has a deviation such that best fit calculation of translation and rotation calculation not zero. So this method clearly wont work.
However, adding circle feature instead of radial cylinder works and best fit calculation is indeed zero. Now if I create circles at each end of the radial cylinder and use them to get a BFBP alignment to be used as suggested in post, then this method of achieving simultaneous requirement is sound?

[[Mi...]]

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If I'm understanding your question correctly (Hard without the drawing) but I don't recommend using BFBP because I couldn't get it to work properly based on the instructions I was given there ( it worked on a part with 6 holes but not a sister part with only 4)

Instead:

Setup a Secondary alignment with the datums properly ( OTE Features and ISO 5459)
Setup a Geometry best fit with the reference selected as the alignment you created in setup 1, select all features required, and in the evaluation constraints check/uncheck whichever ones apply to your callout.

Individually report the the positions of all the various features using the Geometry Best Fit alignment instead of a DRF. If you need to report x/y coordinates of the positions you'll need to translate and rotate each position characteristic to get the Basics that make sense.

[[Ja...]]

In step1 of your secondary alignment, did you use Base alignment as reference or CMM system?

[[Mi...]]

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Base Alignment I've never actually has a use for the CMM System yet.

[[Ja...]]

I am trying to confirm what I am thinking:

If you have a fully constrained DRF without any modifiers ([ LOC | _____ | A|B|C], then is it essential to make best fit bore pattern or a geometry best fit alignment for all position and profile features and using that as alignment for each individual position and profile characteristics or simply using the datum features for each profile and position characteristics will also satisfy simultaneous requirement?