In this Question Line video, Jason answers the following question regarding flatness and parallelism tolerances for a submitted drawing:
I have a spinning that requires a flatness tolerance of .020 on two surfaces. My QC technicians believe I need a parallelism tolerance also. Your thoughts? I’m not sure how to combine the two together.
The submitted drawing is of a flat disk with a raised area in the center. The left and right surfaces are each being controlled with a flatness tolerance, and the designer wants to know if parallelism tolerances should also be included for these features. In this video, Jason explains the difference between flatness and parallelism and gives options on how to tolerance the drawing based on what is critical to the design.
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