Cylinder Probe Qualification

[[Be...]]

I am currently running a Contura with a Vast XXT, I know that it isn't recommended to use a cylinder probe on this machine, but I have a few production pieces that have thin edges, so there really isn't a way around it. Zeiss customer support helped me qualify the cylinder probe last time, but I was a very new operator and I neglected to write down the steps used. Does anyone have this process written down, or could someone familiar with the process just give me an abbreviated run-down?

Thanks.

[[SH...]]

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You should have been helped by me if I was working with xxt. Anyway what type of probe, flat at bottom or hemisphere?

[[Be...]]

This has a flat bottom, I plan to order a cylinder probe with a hemisphere bottom as well.

[[Co...]]

I'm wondering if this topic went anywhere? I am looking to do the same thing this morning. Just built up a 1mm diam x 7mm long cylinder rounded tip on our Contura with an XXT TL3 head and I was searching the forums to see if there was any tips on running qualification as I have never done so with a cylinder tip.

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 or

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did you ever happen to come to a conclusion on this one that you might be able to share? I know this post is 4 years old and I might be reaching a little bit. Thanks!

[[Cl...]]

Why not try this. Probe a point in Z as close as possible to the edge you wish to probe. Create a local (XYZ) alignment from that point. Probe a point on the edge. Now set that point to the alignment you created. Enter a formula in Z  [getActual("Point1").z -0.020] (assuming material is 0.040" thick. You can now probe the point accurately using a spherical probe. Virtual DMIS and I think PC DMIS both have this function built in. Why doesn't Calypso?

Edited June 24

[[Jo...]]

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 I use a 1mm cylinder probe with a hemispheric tip for a thin-walled window with an inconsistent edge that was a problem for our small probe sphere. I have an Accura with a VAST XXT TL3 head.  I qualify the cylinder probe the same as the rest of the probes. (Passive qualification initially, Geo-requalify after).  Surprisingly, I got better results qualifying it on my 25mm cal sphere than I did on my 8mm sphere (My S values range from .00002 to .00063mm on a 15 RDS angle set). My understanding (and I'm no expert) is that because of the way the CMM calculates the probe position using the shaft flex, the cylinder probe will give accurate results close to a standard probe tip when probing at the tip but will lose accuracy as the probing point is closer to the probe base. So, you don't want the probe contact point farther away from the tip than necessary.

[[Dr...]]

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 If the cylinder probe has a hemisphere bottom, shouldn’t it still be able to qualify via the “Sphere” Geometry just like any bona fide spherical stylus would? The reference sphere doesn’t contact anything above the equator, so the procedure couldn’t care less if there’s another half sphere or a cylinder up there. The main thing to contend with is the fact that the cylinder has some tilt – both baked into free state and upon contact, especially with XXTs – so it’s ideal to measure as close to the calibrated hemisphere as possible.

If the cylinder probe has a flat bottom, that’s a totally different story; that’s when the discussion about manually assigning probe values starts. A reworkable reference for disc styli can be found here that may be of use: https://qualityforum.zeiss.com/topic/17980-how-to-qualify-a-cylinder-styli/#comment-101058 (I’d strongly recommend using a spherical artifact, e.g. the reference sphere, in place of a ring gauge).

Cylinder probes aren’t supported on the XXT because your accuracy will be significantly impacted.

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 I think that’s what Edge Points are intended to be as an “all-in-one” function, but I’ve not encountered them in the wild. I think most people prefer doing this with formulas, me and you included.

[[Ri...]]

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I have developed a method of using the Reference Sphere for Disk probes, it does require having another stylus the same length as the disk probe.

It is a tedious task but works exceptionally well.