Radial Hole Pattern as a Datum Feature

In this Question Line video, Jason answers the following questions submitted through our new GD&T Questions submission page: 

Per the attached file, Datum A is determined by radial hole pattern. I have 3 questions:

1. How do you set up the datum reference frame during manufacturing and CMM inspection? Where is the origin point? (0,0,0)
2. How many DOFs (Degrees of Freedom) for the DRF (Datum Reference Frame)?
3. How to apply the MMB (Maximum Material Boundary)?

Jason answers these questions regarding the submitted part shown below, which includes a radial hole pattern as a datum feature.  

Need answers to your GD&T questions? Share them with our experts via our GD&T Questions submission page: 

https://www.gdandtbasics.com/share-your-gdt-questions/ 

While we may not be able to address all questions, we will strive to cover as many as possible. If your question is featured in a video answer, we will notify you and share the video on our YouTube channel. 

* If you are a current student, reach out to us directly and we will get you into contact with your instructor. Active students’ questions receive a direct response within 24-48 hours.