A drill/ream cycle is necessary to produce high quality, large diameter holes in carbon-titanium stacks. Manual tool changes and traditional automatic tool changers limit hole-to-hole cycle times and hole quality. An in-process tool changer, mounted directly on the machine head, replaces a cutting tool with a reaming tool while clamp-up is maintained on the aircraft panel. By reducing or eliminating operator intervention, machine-axis moves, and optical resynchronization, an in-process automatic tool changer shortens cycle time, improves hole quality, and increases positional accuracy of holes. Automating this process also reduces risk of harm to the operator and aircraft structure.