In this Question Line video, Jason answers the following question regarding dimensions identified for inspection:
I had a part manufactured to the incorrect tolerance recently and the rebuttal from the machinist was that I used an inspection dimension and that is purely for QC and is not a driving dimension. Is this correct?
In this video, Jason reviews the submitted drawing, shown above, featuring a dimension marked with an oval. While this oval is often used in industry as a quality control symbol to highlight key features, Jason explains that this practice isn’t formally recognized by ISO or ASME standards for inspection annotations. He emphasizes that every dimension on a drawing is relevant to manufacturing and must meet its specifications—regardless of whether it’s inspected. The discussion also covers related topics such as over-defining a drawing, reference dimensions, and basic dimensions.
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