XXT How slow do i have to go to avoid air scanning?

[[Ro...]]

XXT Articulating head.

Im having a terrible time writing programs and no matter how slow i go i get rescans and "Scanning Optimization".

Im as slow as 0.150 inch on a 1 inch diameter circle to avoid the rescans

Is there a trick i need to know? is there a setting for the Scanning Optimization?

Right now im pretty much using points on all my circles.

[[Ma...]]

You could pre scan a feature with points. I think you can do that in feature projection - not sure exact name, but a few month back it was debated here on forum.

[[Ma...]]

As Martin says you can measure, typically a 4 point circle, I name it Pre-Circle1 prior to your scanned Circle and then go to the scanned circle Projection and choose Ref Feature and select the Pre-Circle1. This will probe the 4 point circle for location then use this circle as the reference location.

[[Ri...]]

As Martin was saying, you could have it probe (4) points before measuring. Projection - Meas. Ref. - Own Geometry. 

Unfortunately this only works for Circles. 😞

As for the optimal speeds, I tend to follow the cookbook when it comes to the XXT. On a 1" diameter, the cookbook would suggest a 2mm/sec for Form, 3mm/sec for Diameter, and 5mm/sec for Position. 

There are times where you are going to get Scanning Optimization no matter what - especially as the feature size gets smaller and smaller. 

You can turn it off in Resources - Compatibility Settings, but please note that it is for the entire measurement plan, not just one feature, so use at your own caution. 

[[Za...]]

aside from what everyone else here mentioned, i'd like to share this Knowledge Base Article on the topic, which discusses a few solutions, depending on what works for you.

https://portal.zeiss.com/knowledge-base?id=443336

[[Ri...]]

I have found that most of my air scanning warnings are due to location of a feature.

It could be from incorrect nominals, or it was machined off nominal, typically this happens when a feature location is as little as .007" from nominal.