How to Calculate Feed Rate


The feed rate is one of the two separate velocities in machine tool cutters. Feed is the rate at which the work moves into the cutter measured in feed per tooth revolution, and is expressed in units of distance per revolution. The feed rate depends on the type of tool as well as on the power available on the spindle. To calculate the feed rate, use a formula that includes different variables.

Step 1

Analyze the width and depth of the cut you made with your tool. Calculate the inches cut.

Step 2

Calculate the speed for the cutter. To find the speed, multiply 4 x speed/diameter. Speed is the recommended speed that your cutter should use, expressed in minutes.

Step 3

Count the number of teeth in the cutter.

Step 4

Calculate the size of the chip load or feed per tooth. This is the size of chip that each tooth of the cutter takes.

Step 5

Put all these variables in this formula: Cutter speed (RPM) x number of teeth (T) x chip load (CL).

Tips and Warnings

  • Always wear safety goggles when cutting and chipping with power tools.


  • Metal Cutting Physics
  • Machine Shop 1 Drilling Machines
Keywords: feed rate, spindle, number of teeth, formula

About this Author

Manuel Páucar (Lima, 1978), is the author of "Chronicles of the Exile," a popular column in the Hispanic market. In his 18 years as a writer, he's published four books and received several awards, including a special recognition from the UNESCO (United Nations Educational, Scientific and Cultural Organization). Páucar attended the Andes Chef School in 1999, and studied theater arts at CTL Institute in 1998.

Article provided by eHow Home & Garden | How to Calculate Feed Rate