True Position and Diametric Deviations

In this Question Line video, Jason answers the following question regarding True Position and diametric deviations: 

When I look up the difference between Position and True Position, I never get an answer on the difference in calculations. The difference in calculations when the ⌀ symbol is in the feature control frame versus when it is not.

Jason reviews the submitted drawing below, noting that the missing diameter symbol in the feature control frame is most likely a typo, as there are very few scenarios that allow dropping the diameter symbol and those scenarios will have a very different dimensioning scheme. 

In this video, Jason first clarifies the difference between Position and True Position. He then walks through the process of determining whether the given measurement values result in a passing part – explaining how to calculate diametric deviations, potential bonus tolerance due use of the MMC modifier, and the effect of the MMB modifier.  

 

For more information: 

Difference between Position and True Position: Position Tolerance vs “True Position” 

Calculating Diametric Deviation: Position Calculator 

Use of the MMC and MMB modifiers: When to Use MMC and MMB 

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