When is Main alignment needed after pre-alignment?

[[Pa...]]

Hi All,
 

I have a general question regarding alignments in ZEISS INSPECT.

In my workflow, I use Pre-Alignment to initially bring the CAD model and the mesh into the same coordinate system. After achieving a good pre-alignment, is it always necessary to create a Main Alignment as well?

I would like to understand:

• What is the specific purpose of a Main Alignment compared to a Pre-Alignment?
• In which situations is a Main Alignment mandatory or recommended?
• If pre-alignment works fine, could those evaluations be used with confidence?

I would appreciate any guidance or best practices regarding when to use Pre-Alignment only versus when a Main Alignment should be added.

Thanks in advance for your help!

[[Ma...]]

Hi,

you can use only pre-alignment if you have good quality of parts - bended and differentiating mesh against CAD model can lead to bad pre-alignment and your nominal elements may be not calculated.

Many drawings have RPS and other datum definitions, so you may need alignments or at least datum systems.

While using heat map of deviations you want them to be stable, so you would need to make main alignment for that.
Also you would like to know what those deviations are teling you.

If you have bended parts, then you would need for calculations of elements bestfitting - which will bring mesh closer to nominal element and allow calculation.

While you ask for this type of question i would ask with what measuring machine you have knowledge.
We are using here ScanMaxes, so to get comparable results we had to use geometry norm instead of ISO/ASME.

Also i would suggest training - it's not that simple how it looks - you may have wrong results at reports due overlooked method.