Q for those of you who have an XXT

[[Ro...]]

I don't have an XXT, but our sister plants all do.
So i'm doing some online tech support to one of our other plants and we noticed that 1 of the angles that's being used in the program isn't being qualified by the auto program.
That was an easy fix to add the angle, but now when running the auto program he noticed that some tips within the same stylus system take Points during qual and some angles are doing the helix scan.
The guy asks me "what method is better, what should i use?" and i'm like, "I don't understand why there is even a choice, if 1 method is the better method, then why am i given the opportunity to do it a lesser way?"
for a daily Qual should i use Geometry Requal or Qualify Passive?

and no we got the problem where the probe head moves to an angle, say 90, 90 then doesn't qualify that angle, just moves on to another angle. What was that all about?????

Whats the deal with XXT qualification? Our detroit plant had lots of problems with qualification and even had a tech onsite 2 or 3 times before it got figured out (and by figured out, i mean they found a way to stop it from throwing err windows) .

[[Ri...]]

Qualify Passive is performing the calculation of the bending parameters. Typically this is only needed when you first qualify that probe as the bending parameters shouldn't ever change.

Geometry Re-qualification takes 5 points at the end, and if you watch the Qualify Passive, it's doing the same thing. This is where the calculation of the geometry is taken.

I've always been told that you should only have to do Geometry Re-qualification after you've done Qualify Passive. I've heard arguments against this, but no tangible data to support it.

I would say if you have an active scanning head, to always do Tensor/Dynamic Tensor as I have data that shows how much better of a qualification that is to Geometry Re-qualification.

[[Da...]]

I used to use an xxt head and there's a couple things you should know. First off the multi position calibration that is supposed to qualify ALL angles NEVER worked correctly for me. I tested this by making a simple program that touched a part with a Z point. ran it three times then changed the angle and ran it again. I did this for various angles and I found a deviation of .0004 " . 😮 Not too cool. So to be able to use the other angles I started qualifying them as separate styli. Variation dropped to .00008. 😃

Since I didn't need all the angles available this worked quite well. All the styli you have programmed will be re run during a qualification.

I would love to see what you all get when you run the test. I did this almost ten years ago so it may have improved since then.

I think the error may have to do with the weight of the stylus. It would be very different when horizontal, as opposed to vertical. That's just my opinion. 😕

[[Ja...]]

We use XXT. As far as I remember, when the probe moves to an angle, doesn't qualify, and moves on, this was because the shaft radius of the qualification sphere was too large and the machine thought it would crash at that angle. I added a "second" reference sphere with a smaller shaft radius (same artifact, just different radius/name) and it calibrated the angles. **With a second reference sphere, you need to use Masterprobe to locate each before you start calibration.** Or you can physically rotate the reference sphere and do a second pass for the angles that didn't calibrate the first time through.

We use Geometry Re-qual for daily qualification. Some tips are taking scans and some are taking points because not all are set to Geometry Re-qual.

We have just over 83 different tip angles over 11 tips and Geo Requal takes about 45 minutes per day. Qualify Passive would take just over 4 hours. I have head the same as Richard in that you need to do Passive when the probe is new/change in the stylus system.

[[Ri...]]

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It should always be stated that the RDS-CAA qualification is not meant for tight tolerances. It is for time saving. It does 12 positions and does a mathematical calculation. There are enormous factors that are going to cause uncertainties in that calculation.

If you want accuracy, you always manually define and qualify each position.

[[Da...]]

It should always be stated that the RDS-CAA qualification is not meant for tight tolerances. It is for time saving. It does 12 positions and does a mathematical calculation. There are enormous factors that are going to cause uncertainties in that calculation.

If you want accuracy, you always manually define and qualify each position.
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It used to say that somewhere in the sales brochure, but I can't find it now.

[[Ro...]]

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So did you ever try and edit the shaft radius of your Reference sphere instead of creating a new one?
Seems like a lot of extra work having 2 spheres.

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[[Ja...]]

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I'm sure that I could go in and fine-tune a shaft radius, but I think what was happening was I'd make it smaller to allow certain angles to calibrate and then others would actually start to bump the shaft. I'll have to sit down and calculate the ideal shaft radius because you're right, it takes a little more time having to reference "another sphere" every day. But it beats them not calibrating certain angles and never noticing 😱