This video graphically illustrates the sort of metal removal rate that is possible in aluminum when a milling machine is run at its most dynamically stable spindle speed. Note the relatively quiet sound of the cut.
The cut actually is just a demonstration, because this feed rate would impair the machine’s ability to hold fine tolerances. The video was provided by Boeing’s Research and Technology group in St. Louis, Missouri. For more information on milling at dynamically stable speeds, see the article under “Editor Picks” at right.