Jump to content

True position of different probes


Recommended Posts

I am trying to get the True position of a feature using multiple probes. All of our probes are calibrated and the sigma is very low, although we did not use the same method for all the probes. If we do a alignment with 1 probe and then check the True position is is great( to be expected), but if we us a different probe than the one used for the alignment it is bad. I would think it would come out good allowing for some small differences between probes. We are getting more later 0.001 inch difference. Any ideas?
Link to comment
https://qualityforum.zeiss.com/topic/14640-true-position-of-different-probes/
Share on other sites

Please sign in to view this quote.

Are you scanning the features??
It can be solved by gauge correction....
Do one thing measure sphere in the reference sphere using each probe with same strategy and evaluation. If you got Different x,y,z values definitely problem in your probes.
My experience shows that 3 effects are most of time chould be the reason:
1st: Stylus system at e.g. 20 ° C qualified, but we measure at 25 ° C. Depending on the total length and the position in the probe head, elongation becomes noticeable (better use high-quality CarbonFiber extensions, none made of aluminum).
2nd: Stylus system change
The reproducibility of the change is approx. 1 arc second => 1 µm with a probe length of 200 mm. Therefore avoid changing stylus systems.
3rd: Position calulation by outer- or inner tangent element. A different form deviation shifts the centre).

General rule
High-quality stylus components
Very good air conditioning (short-term stability are very important).
Optimized filter and outlier elimination.
×
×
  • Create New...