Machinists also determine how fast to feed the metal into the machine and how much metal to remove. Next they select materials and tools for the job and plan the sequence of cutting and finishing. The final planning step is to mark the metal to show where the cuts should be made. The machining stage begins with the machinist positioning the metal on the first machine tool. Then they set the controls and make the cuts.
New machinery allows various functions to be performed with one setup.
During machining, machinists constantly monitor the speed and feed of the machine. They also check that the metal is properly lubricated and cooled. Most machinists produce small batches of one item or one special item at a time. Production machinists, however, may produce large numbers of the same part. Other machinists do maintenance work, such as making new parts for existing machinery.