observation-during-the-finishing-process312431 Spark appearance2 Tarnishing and annealing colors3 Tool wear4 Grooves13221 Chip appearance2 Tarnishing and annealing colors3 Tool wearImportant observations can be made during thefinishing process that allow conclusions regarding quality.Whistling sounds duringa machining processmay indicatedangerous bladevibrations. Unusual discolorationor an unusual reflection behaviorUnusual bubbles