Polar Shape of Zone Illustration

[[Da...]]

Hello all,

I'm working on a part that has a lot of positional tolerance callouts on dowel pins and bolt circles on a multi-faceted hemisphere. For position characteristics of single features like dowel pins, I'm using a polar tolerance zone since that one seems to give the most realistic results. I am, however, wondering what the shape of this polar tolerance zone actually looks like. Can anyone shed some light on this for me?

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[[Er...]]

From my understanding a Polar coordinate shape would include all directions, or in other words, this would be a spherical shaped tolerance zone. I have not had to use this before though so I could be mistaken.

[[Je...]]

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I agree with Eric. The shape of the zone is spherical. You have the option in the position window to limit evaluation to any combination of the x,y and z axis.

Also, I'm jealous. That looks like a fun part to measure!
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[[He...]]

Polar zone is the shape of a cylinder. The difference between the polar and the normal 2d diametrical is that polar tilts the tolerance zone so it follows the nominal direction of the feature. This makes it possible to inspect an angled hole without tilting the coordinate system. Seems like a good solution for the current part but it can be annoying to analyze non conformances in three dimensions.

[[Da...]]

Thanks for the feedback, everyone. I tend to lean toward what Henrik mentioned as that makes the most sense to me. It's too bad that isn't an option for bolt patterns. For bolt patterns I end up having to rotate the reference frame normal to each facet.

And Jeff, yeah it was fun but a challenging part for sure. It's about 1.3 meters in diameter and I only have 1.6m of measurable length along X on my machine.

[[Ph...]]

Is that the new and improved version that actually works??

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