Hi IAN, THe 3d approach to probing currently used is known as the bed of nails approach. It is basically probed with just the z axis going up and down and the positions are moved by the xy axis. The height of z when it trips is recorded along with the xy position. The height of the z is really only relative to the reference height of the part. In the trip point file the only thing relative is the relation of the lowest and highest points as a reference so the true position of z is not needed and the position of xy is relative only to the grid you probed on. You will end up with 1000s of points that have to be converted to a skin, later to be carved out by MACH
In CMM type probing you are actually probing in the x,y and z planes and the radius of the probe tip AND any movement error associated with the length of the probe arm AND the direction of axis TRAVEL HAVE to be corrected to give you the exact touch point center line. THat way you have an exactly replication of the coordinate values needed to recreate the surfaces probed. You will only need the coordinates neccassary to recreate the surface. For a straight surface you will only need a start point end point and a base height and top height point to draw the surface. For curves you will need to collect curve data in order to recreate it..
Please don't be TOO hard on them about the cv. It can be a beast to impliment across the extremely broad range of equipment types it is being used on.
It would be a piece of cake if it was only used on one exact type of machine. Then it could be fine tuned to the conditions relatively easy. I find most problems are machine/operator generated. Too small of drives for machine, and too fast of settings for conditions, or getting heavy on the FRO (;-)
Hope that helps (;-) TP