Rub hole-bar measurement

Abstract

A method of determining a fan liner blade tip clearance includes providing a measurement instrument. The measurement instrument includes a set screw, and a base including threaded through hole configured to accept the set screw. The method also includes placing a bottom surface of the base against the fan liner wherein the through hole aligns with a wear hole of the fan liner, and after the placement, turning the set screw within the through hole until a bottom surface of the set screw contacts a lower surface of the wear hole. The method also includes measuring an exposed portion of the set screw extending below the bottom surface of the base after contact with the lower surface of the wear hole is made, and determining a blade tip clearance with the fan liner based on a value of the measurement.

Dependencies are inferred from the claim text.