What is the maximum tolerance you should allow when measuring a machined part?

The maximum tolerance you should allow when measuring a machined part is determined by the specified tolerance limits of the part, which are typically outlined in the engineering drawings and specifications. These limits are set based on the design requirements, function of the part, and the machining processes used.

Understanding and adhering to these specified tolerances is critical because they ensure the part will fit and perform as intended in its application. For instance, a part that has tight tolerances will require more precision during machining and inspection, while parts with looser tolerances may allow for slightly more variation.

The other options suggest fixed or generic tolerance values that may not apply universally to all parts. Machine capability also plays a role, but ultimately, the tolerance limits defined for each part are what should guide the measurement process.