Probing Point Issues

[[Me...]]

Good morning, everyone. I just started a new company and have run into an issue with pulling circles off of a CAD model.

I'm pulling circles off of outside curved surfaces via a CAD model, setting things up as normal. But when I run my program, I noticed that every outside circle's points are vectored in a downward angle in the Z. I believe this is throwing off my diameters. All the other features seem to be ok...?

Any ideas? thanks.

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[[Cl...]]

You see this after the feature has been measured? Are you using a star probe?

Used a star probe to measure a cylinder. This is what I see. According to Zeiss, this is acceptable.

[[Me...]]

Yeah, I'm using a Start Probe on a Duramax.

[[Ri...]]

What happens if you slow down your scan speed? What is your scan speed? Do you see the same problem with single points?

[[Me...]]

I'm not scanning. That's what has me scratching my head. I've even slowed down my approach speed.

[[To...]]

The XXT sensor, by nature, measures points by deflecting the probe. When you qualify the probe, the various "probing behaviors" are determined by a certain amount of deflection on the probe. Another way to look at this, is you are purposely tilting the probe when you take a point. This is really evident when you're using a star probe.

You say it is affecting your diameter results. How do you know? Your form and sigma values are zero. That, to me, is a good sign. However, you have a relatively small arc segment. What I would do is go to Size - Standards - Radius Measurement and select Radius Measurement. Assign the circle. Click OK. Then, click Calculate Now. Then, View your report. This will constrain the X and Y location and give you a distance to each point from a theoretically perfect center. Check your results. If they're relatively consistent, then the results should be relatively dependable. Unfortunately, you'll be working with radius values and not diameters. But this may be enough to get you on the right track.
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[[Ri...]]

I've been playing around with this most of the afternoon and my data looks perfect. The vector data comes from the Geo Actuals file and is data prior to any geometry calculation or probe compensation. That is my best guess anyway. It can be useful to look at the green arrows in the CAD window for a feature and if there are some crazy arrows, pointing way off, then you can safely guess that you've got a problem.

[[Me...]]

I've had an issue similar to this. The CAD model itself seemed to be the problem.

What type of CAD file are you using? Did you have to convert it to open it in Calypso?

Have you tried recreating the feature, not using the model?