where D is the diameter of the workpiece in mm. The above equation is used to calculate spindle speed for milling or other material removal processes. The spindle speed also affects the feed rate FrF_\mathrm{r}Fr​, in m/min, for the machining operations. The feed rate is defined as the amount of material being fed into the tool in length per unit time. The feed rate calculation formula for a machine having Z teeth is given by the equation:

Find the spindle speed for milling a steel workpiece having a diameter of 20 mm. Take cutting speed V to be 5 m/min. Also, determine the feed rate for a single tooth having feed per tooth of 10 mm.

where FtF_\mathrm{t}Ft​ is the feed per tooth in mm. You can also use our taper calculator to calculate parameters tapering a workpiece.

To perform said operations, they must operate on the right spindle speeds as well as feeding rate to maintain dimensional accuracy of the workpiece and finished product. The article explains what spindle speed is and how to calculate spindle speed and the feed rate calculation. After the example exercise, you'll be able to calculate spindle speed for milling or lathe operations.

The spindle speed NsN_\mathrm{s}Ns​, in rpm, for a machined operating at cutting speed V, in m/min, is given by the spindle speed formula:

The spindle speed calculator will assist you in determining the appropriate speed and feed rates to perform any lathe or milling operation. These heavy-duty machines are the backbone of the manufacturing industry and are used for material removal processes such as turning, facing, milling, finishing, knurling, grooving, etc.

We also have a speeds and feeds calculator and material removal rate calculator to calculate machining parameters for different operations.

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It is the rate at which the workpiece is fed into the tool or vice versa. It is measured as the length of the workpiece per time.

The spindle speed is defined as the rotational speed of the spindle of the machine. In lathe or CNC machines, the workpiece is attached to the chuck, which is attached to the spindle. Apart from the lathe, the spindle holds drill bits in the chuck, grinding wheels, and milling or shaping tools. The tool would get regular wear and tear from its interaction with the workpiece during the material removal process. The spindle speed affects the surface finish of the workpiece and also the longevity of the cutting tool.