Cylinder probe calibration issues

can you show us your calibration settings?

Is this what you mean??

5 hits is literally the bare minimum.... I would use 13 hits in DCC mode.  also check mark the shank Qual box but make sure your offset is correct. being that it says 1, are your units MM? that's how far down it will shift to take 8 hits around the upper shank, this will give you IJK values. your results will be much better.

Thanks DMIS_guy for your reply. I have to check that job again today.

The 5 hits was, I guess, the default? I changed it to 13 like you said. The shank qual box is now checked.  Yes, it's in MM (all of our prints are in MM).

The 1st time I calibrated it w/ the new settings, it checked like it always does the 1st time I calibrate it - BIG and it exceeded the limits. (See below.)




Then I "reset" the probe tip and it came out better - BUT the diameter is STILL reading about 50+ microns big. (See below.)
That's ok for THIS job, since I only need to use the bottom of the probe. Obviously it won't be if I ever need to use the sides of it.



WHY do I have to "reset" this probe tip everytime?? I've never had to do that w/ any of the other probes I've ever calibrated. 

Almost all of our tips use the "reset tips" checkbox in the measure window. I believe this is so that it doesn't used old stored data from a previous calibration's measured value and sets the tips back to theo values instead of keeping that meas value. Try calibrating this tip 0,0 again without using reset tips and see if the data changes.

It changed again when I calibrated it. It went back to almost the same #s as before. I knew it wouldn't be good because I could see it going around the sphere above the equator.



Hit "Reset" and cal'd again and got...

Sometimes probe files get corrupted. I would delete the probe and recreate it.  Also it's good practice to always "reset tips" before each calibration.  If you use the probe builder wizard make sure your geometry matches the actual probe.

Rusty91307  As I've mentioned before, there is a 1mm offset being introduced to the length from somewhere.  The THEO length is 13.075mm.  The first time you calibrate after resetting the tip, The MEAS length is set to the same as the THEO and PC-DMIS uses that length to drive the tip around the cal sphere.  It then updates the MEAS length to what was actually recorded during the calibration which is where your 1mm offset gets added in.  The next time you calibrate, PC-DMIS uses the updated MEAS length to drive the probe around the sphere and it tries to take hits 1mm higher up.  Because it is a flat bottomed cylinder, rather than a sphere, the corner of the cylinder hits higher up the sphere and the diameter shows out.

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This can ONLY happen if one or more of the components making up your probe build has a different physical length than the one that is defined.  You have previously told me that you've measured your cylinder component and that it has the correct length, what about other components - extensions, probe module, indexing head, adaptors between the head and the Z ram?  Have you looked at the results for all of your other probe builds to see if any of those have differences between their THEO and measured lengths?

Shank qualification check box  was disable. 

Shank qualification check box  was disable.