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This is fine, but not typical for cylindrical faces. The Profile GD&T symbol describes a 3D tolerance zone around the face, and as such is typically used for complex surfaces where other symbols cannot be used. See


If the request is coming from whoever will be machining or inspecting the part, I would side with them. They know what they need to see to make sure the part ultimately meets the print. Also, since your first datum is on the opposing face this implies it is getting machined first, hence why it is a reference datum. The geometry of the face you're making the ...


Assuming the limitation is power/heat buildup... The power dissipated in the motor winding is a square function... if you decrease the voltage by 50% (and therefore the current) you have decreased the power by a factor of 4... down to 25% of its original value. Any motor rated to run for 25min "ON" time, and at 80% duty cycle, will surely have no ...


Typically in my experience, your 3 orthogonal edges of the rectangular blank are your first 3 datums. Your dowel hole would be the first machined feature and since it locates the rest of the features, this would be your 4th datum. Your subsequent features would reference that 4th datum, as well as any of the original 3 to tolerance the features.

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