I haven't had to dimension total runout yet programming. I am fairly new with programming and was looking for some advice on the best way to dimension these Total Runout callouts.
Just probe your datums (avoid circles and go with Cylinders) with many points and do the same for the features you are called to dimension (make sure to probe cylinders in multiple rows). Switch away from legacy dimensioning and create the runout call outs as you see them exactly. If you have a scanning head go with scanning. Not really different from any other call out there.
If you want to use legacy, select the runout feature first, and the datum second.
I prefer to use a auto cylinder spiral scan for the feature with a reasonably tight pitch to mimic a hard gage if possible.
Concentric circle scan for the Datum.
Yes it will, which kind of dimensioning are you trying to use and what version of PC-DMIS are you running? Both XactMeasure and the Geometric tolerance command will allow you to pick two datums for total runout, it is only legacy dimensioning that will not. That is because legacy does not typically use datums, it is based off the active alignment instead so the onus is on the user to interpret the callout and create an alignment that simulates the datum reference frame.
You need to measure datum A as a plane, spreading the hits over as much of the surface as possible and then level to it. You then need to measure datum B as a cylinder, create a pierce point between A and B and origin to it. You can then measure your other cylinders and planes and report total runout back to the active alignment using legacy.
It will depend on how square the cylinder is to the plane. When you origin to the cylinder it will use the axis average. By creating a pierce point to use as the origin, it makes the alignment more repeatable and more closely simulates the way the datum reference frame would work.
