Jump to content

CMM vs CMM


---
 Share

Recommended Posts

Please sign in to view this quote.

That's a trick question, yes?
What types of features?
Precision ground parts? Plastic Injection Molded? Assemblies?
I would expect different variations for various reasons.
Link to comment
Share on other sites

I'd expect roughly 10 microns. This is our difference between a Contura (in a controlled environment) and our Accura (shop floor environment). Your variation would depend on your environment more than the different equipment.
Link to comment
Share on other sites

Both in controlled environments, but one fluctuates considerably
more than the other, (plus/minus 5 degrees). Parts are medical
device, titanium & SS. Tolerances anywhere from .0005 - .005".
Link to comment
Share on other sites

I would expect no variation. I did once noticed about a 5 micron difference between our contura and Duramax on one part program, one feature measurement. I never was able pin point the reason but I have never seen the problem again. I don't usually look at, or beyond 5 microns though.
Link to comment
Share on other sites

If its in a controlled environment I wouldn't expect to see much difference at all, for the machines to pass the calibration it depends on the machines but even on a Duramax its like 2.4 microns. If its not a controlled environment you can see a lot of variation. a couple .0001s easy depending on the material.
Link to comment
Share on other sites

Please sign in to view this quote.

+/- 5 degrees is a little much, but I still think you should be able to be within a few microns... Hopefully, the temperature swing is a slow one. In rooms with larger fluctuations, it is much more important to have a recent probe calibrations. When I was chasing microns in an ISO 17025 Lab, I would need to re-calibrate if the temp changed by more than a degree.
Link to comment
Share on other sites

We are seeing about .0004" variation machine to machine. Zeiss came in and did
some verifications, and found nothing wrong with the head (RDS/XXT) or the machine.
Link to comment
Share on other sites

Thermal coefficient of expansion between tititanium and the many types of stainless can vary significantly as well as how long one retains the heat.
That aside, I'd have to question fixturing and man.
Link to comment
Share on other sites

 Share

×
×
  • Create New...