In this Question Line video, Jason answers the following question regarding Rule #1 and title block tolerances:  

I do have a GD&T question for you that puzzles me. It concerns Rule #1. My company is using the 2018 version of ASME Y14.5, but I don’t think it matters between that & 2009. Our default angle tolerance found in our title block is ±.5°. There is a bar that is dimensioned 10±.25” long, 3” wide, and .5” thick. I know the overall length can be measured from 9.75 to 10.25 long. My question is: Could you get a part that looks like Result A (since Rule #1 applies and default angle tolerance is NOT taken into account) or does the default angle tolerance taken into account and a part would look more like Result #2?

The figure below includes the examples provided by the student: 

 

In this video, Jason explains that in addition to size tolerances and Rule #1, angular tolerances must also be taken into account when determining whether this part passes inspection. Though the dimension of the angle in question is not specified on the drawing, he explains that because the surfaces appear to be perpendicular, this angle is implied to be 90° per ASME Y14.5. To determine the tolerance on the implied 90° angle, reference the title block for the default tolerance value of an unspecified angular tolerance. 



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