Machining an out-of-round bore is easy if you're not particular about the location or magnitude of the roundness error. But accurately machining a hole that has a precisely defined non-round profile is a capability that would seem to be well beyond what a standard boring bar can accomplish. A...
Many theories have surfaced on exactly who has machined the world's smallest hole. The topic has been debated around the globe. But Makino has done it in Japan on a communications /fiber optic part -a stunning 0.00044 inch finished hole diameter, and was cut on the Makino EDGE2 Sinker EDM machine...