How to set up bolt circle diameter

[[Ad...]]

currently using a pattern to measure 4 circles 

creating a theoretical circle from these 4 circles

the diameter of the theoretical circle is smaller diameter than when i use the R value in a caliper distance.

what am i doing wrong? 

[[To...]]

Please sign in to view this quote.

my guess is you used "Recall Feature Points" instead of "Recall".

[[Ad...]]

Please sign in to view this quote.

that is correct - is that my issue? i will give it a go & see if the values change

[[Ma...]]

Recall - it will recall origin point of selected feature/s
Recall feature - it will recall measured actuals into features nominals - that's why you cal recall only one feature
Recall Feature Points - it will recall all measured points into feature - used when measuring 4 single planes but need to have one from all data

[[Ky...]]

Just as a graphical description of what Martin is saying, this is what you get when you use recall:

 

This is what you get when you do recall feature points:

 

Since you are taking every individual point measured in the circles describing the bore pattern, you get odd results. This document on the knowledge base describes how to set up bore patterns properly:
https://portal.zeiss.com/knowledge-base?id=1769725

 

Hope that helps.