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

Your video mentions a polar probe or a TIR checker. It’d be cool if you included slightly more details on those types of tests to educate people.

This question was in response to a recent video about the issues inherent with measuring runout and circularity using V-Blocks. In the video below, Jason gives a high-level overview of how polar probes and TIR checkers are used to inspect circularity or cylindricity.

 

 

If you have a GD&T question that you would like ask our experts, they can be submitted here:

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

We can’t promise to answer them all, but we will try our best! We will notify you if your question is selected for a video answer, and the video will be posted to 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.


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