Primary / Secondary alignment to better locate part

[[Jo...]]

I have inherited a lab with a Zeiss CMM using Calypso software and the programs do not seem to sufficiently locate the part. Details are below, but my main question is: The base alignment is being used in all programs as a fixture location, so what method do I use to add a part location/alignment to find the closure more precisely before I start my actual measurements? How do I do that if I want it to repeat for all locations on the pallet?

I have looked through the programs, and here is what I have found:
They used a base alignment (called Base alignment) to locate the large fixture. They are using 3,2,1 to get the origin as seen in the picture. This is done without the “brown” plate and closures loaded. This seems to be fairly solid location of the top blue plate, and it doesn’t move unless the fixture is removed and reset, which only happens during annual calibration.
They wrote the programs on a part located in the bottom left position. Then use autorun with the grid pattern to repeat on all 64 pieces.
The problem is, there is enough “slop” in the installation of the brown plate, and the closure can move around in the cutouts of that plate as well and the probe is missing the closure for 1/3 to 1/2 of the auto circle. I reran base alignment and the probe went from off by 1/4 inch to off by an amount small enough I can’t quantify it, but it is enough that the measurements are not being performed properly. What method do I use to add a Part location/alignment to find the closure before I start my actual measurements?

Sorry for the long post. Trying to get all eeh information that I see is commonly asked for by those helping!

[[Cl...]]

If you perform a search (Pallet Program) of the forum, you should find plenty of info on a solution or improvement for this.
I would start though by fixing or re-designing the brown plate/fixture. Adding a loop to the Base Alignment wouldn't hurt.
I'd look through the program (every feature/characteristic/alignment) and doublecheck that everything is correct.