I have a cylindrical feature that is designated as a true position from datum F and datum B on a drawing. My part is aligned to so that the z plane is my A datum, my x plane is my B datum and have created a plane which represent the F datum. When I set up the part and input all necessary information for my cylinder feature everything works properly and the part measures within the specified limits. When the program is executed for my inspection the part no longer is in spec when measured to the required datums. Any ideas or is more information needed?
A manual alignment should always be followed by a DCC alignment. the DCC takes out human error. You could get different reading between the two. That also goes for measuring the part in DCC verses manual measurements in writing it. If you can post your code maybe someone might be able to see someing else.
DCC = Direct Computer Control
In other words, the CMM is running automatically. Not an operator taking the touches.
See as you posted this in the portable forum and have no info about the type of machine you have, it is hard to give an answer.
Can you fill in those details?
Perhaps post some of the code?
Also describe your method of taking hits?
Have you measured this feature using other methods? (caliper, mic, pin gages, etc)
If you are using a Romer Arm, you can't perform a DCC alignment. Your only option is a manual alignment. As John Kingston said, can you give us more info.
