SCANNING SP25

[VONDY]

WHEN SCANNING I AM GETTING TRAILERS, USUALLY AT THE START OR END OF SCAN. WHEN I REPORT THIS SCAN OUT FOR PROFILE IT WILL SAY IT IS OUT OF TOLERANCE BUT WHEN YOU LOOK AT THE SCAN YOU CAN SEE THAT IT IS A TRAILER OR MORE THAT IS BAD. FIRST, IS THERE A WAY TO JUST DELETE THESE TRAILERS SO THE REPORT SHOWS GOOD. SECOND, IS THERE A WAY TO HAVE THE SCAN SET UP TO EXCLUDE THESE FALSE HITS. I HAVE A .00025" PROFILE TO HOLD AND ALL THE HITS SEEM TO FALL WITHIN THIS RANGE EXCEPT FOR THE TRAILERS AT THE BEGINNING OF MOST AND JUST A COUPLE AT THE END. I CONSTRUCT A SPHERE ALSO OUT OF ALL THE SCANS BECAUSE IT IS A GAGE THAT HAS A SPHERICAL RADIUS OF .0005" WITH A LOCATION HELD TO ±.0005.

[Sean Harris]

If you are using 3.6 or above construct a filter set and select remove outliers. If you are using 3.5 or below try to change your start, stop points until the outliers are gone.

[JamesMannes]

As Sean said, what version are you using? Also, what king of machine are you using? A tolerance range of .00025" is not too realistic for a CMM is it?

[Matthew D. Hoedeman]

Yeah, if you are trying to check a tolerance of 0.00025", then your machine needs to be calibrated, repeatable, and speced to 0.000025". Remember the 10% rule, the measurement device NEEDS to be capable of 1/10 (10%) of the tolerance you are checking to.

[Sean Harris]

1/4 for ISO these days. While I am not arguing for it, it is the rule. So need to be cert'ed for .000625 or 1.5ish microns, which is possible that they are but not likely.

[Matthew D. Hoedeman]

I think you left out a zero or 2, with a +/-0.00025, at 1/4, the CMM would need to be 0.0000625".

[Sean Harris]

correct, sorry I did leave off a zero. its 4 zeros and a 625.

[VONDY]

If you are using 3.6 or above construct a filter set and select remove outliers. If you are using 3.5 or below try to change your start, stop points until the outliers are gone.

new 12-22-10 B&S Advantage with sp25 version 4.0