Flute grinding removes large volumes of material while manufacturing cutting tools and the resulting wheel wear makes it difficult to maintain a high tolerance on core diameter during lights-out manufacturing of large batch quantities. The built-in ruby probe is ANCA's in-process solution to measure, compensate and maintain core diameter stability within specified tolerances. The ruby probe operations will perform a core searching algorithm that finds the deepest point of the flute. All fluting operations are supported for this function and the digitising results can be viewed through its display option and can be exported to a file after the cycle finishes. The ruby probe can be used on all ANCA machine platforms.