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Probe Calibration issue.

Hi,

I have a Probe Calibration Issue. When I try to Calibrate the probe it is as if it is forgetting where the sphere is and the Scans within the calibration aren't touching the sphere itself. They are missing the sphere on one side and then hitting the sphere eventually as the Scan continues to the end.
I have bult new probes within PCDMIs and built a new probe physically. I have checked to see if the head is square and it seems to be although I am not 100% on how to do this.
I appreciate any input.

Cian
  • Did you try a standard calibration (ttp) and say "yes" to "did the sphere moved" ?
  • What type of probing are you using? (Reminds me of SP25's per your description)
    Have you tried selecting the radio button next to 'Reset tips to Theo at start of calibration'?
    Have you double checked to make sure nothing has changed in your sphere's(tool) description?
  • I still have this issue once in a while with 97.5 and 105 angles whenever I build a new probe. I just switch to man+dcc for those angles, then after that you can switch back to dcc+dcc.
  • Hi,

    I have a Probe Calibration Issue. When I try to Calibrate the probe it is as if it is forgetting where the sphere is and the Scans within the calibration aren't touching the sphere itself. They are missing the sphere on one side and then hitting the sphere eventually as the Scan continues to the end.
    I have bult new probes within PCDMIs and built a new probe physically. I have checked to see if the head is square and it seems to be although I am not 100% on how to do this.
    I appreciate any input.

    Cian


    Hello and welcome to the forum!

    Step 1: Make absolutely sure you're running PC-DMIS with full Admin Rights. This is required so that when you locate the qual sphere the data is permanently saved.

    Step 2: One of your probes needs to be a short stiff stylus, like a 5x20 or similiar. This one we'll nickname The Master Probe.
    Load up Master Probe and choose only A0 B0, and when you go to calibrate it say 'Yes Sphere Moved Manual Hit'.

    Step 3: After it's done, OK out of the Probe Utilities Dialog. This important little step actually saves the sphere location data.

    Step 4: When you build a probe, make absolutely sure your "virtual" build in the Probe Utilities Dialog perfectly matches each and every component of your "real life" probe build. Never take shortcuts like assuming that a 2x40 is the same as a 2x20 with 20 extension.

    Step 5: Calibrate your new probes and be sure and choose No Sphere Not Moved...

    ...until the sphere does get moved. When it gets moved, go back to Step 2 and use Master Probe A0 B0 to re-locate it.

    Best Practice:
    Never take a 'Yes Sphere Moved Manual Hit' with any probe other than Master Probe, or any angle other than A0 B0.

    Important:
    If you reboot the PC and the CMM forgets the sphere location, then you are running with insufficient Admin rights. Get your IT department involved, and if they refuse to give you full Admin rights... simply shut the machine down and politely explain to your mgmt that IT won't let the machine function.
  • I still have this issue once in a while with 97.5 and 105 angles whenever I build a new probe. I just switch to man+dcc for those angles, then after that you can switch back to dcc+dcc.


    This is a case of a discrepancy in virtual build vs real build, either in the new probe or worse yet the master probe. This should not happen.

    What may happen is colliding with the sphere's stem, which can be resolved by mounting the sphere tilted and creating new Qual Tool definitions with tilted IJKs to match.

  • Best Practice:
    Never take a 'Yes Sphere Moved Manual Hit' with any probe other than Master Probe, or any angle other than A0 B0.


    If i was on Facebook, I'd give you a 'Like' for that.
    In other words, +1
    ProbeCal is the root of all precision...Sunglasses
  • What type of probing are you using? (Reminds me of SP25's per your description)
    Have you tried selecting the radio button next to 'Reset tips to Theo at start of calibration'?
    Have you double checked to make sure nothing has changed in your sphere's(tool) description?


    It is SP25! I will try your suggestions and let you know how it goes.