Determine the spindle speed (RPM) and feed rate (IPM) for a milling operation, as well as the cut time for a given cut length. Milling operations remove material by feeding a workpiece into a rotating cutting tool with sharp teeth, such as an end mill or face mill. Calculations use the desired tool diameter, number of teeth, cutting speed, and cutting feed, which should be chosen based on the specific cutting conditions, including the workpiece material and tool material.

Calculate the horsepower required for a milling operation based on the feed rate and depth of cut, which are used to determine the material removal rate (or metal removal rate). Also required is the unit power, which is a material property describing the amount of power required to cut that material. The horsepower at both the spindle and the motor are shown, as well as the spindle torque for a given spindle speed (RPM). The motor horsepower required for the milling operation can then be compared to the horsepower capability of the machine.

In many milling operations, the cutting tool must step over and make several adjacent cuts to complete machining a feature. As a result, a small cusp of material, called a scallop, will remain between these cuts on any surrounding walls or on the machined surface if a ball end mill is used. The size of the step-over distance and the tool diameter will determine the scallop height between each step. Decreasing the step-over distance will minimize the scallop height, but will require more steps, and therefore more time, to machine the feature.

Determine the spindle speed (RPM) and feed rate (IPM) for a drilling operation, as well as the cut time for a given cut length. Drilling operations are those in which a cutting tool with sharp teeth, such as a twist drill, rotates and feeds into the workpiece axially, forming a hole with a diameter equal to that of the tool. Calculations use the desired tool diameter, cutting speed, and cutting feed, which should be chosen based on the specific cutting conditions, including the workpiece material and tool material.

Calculate the horsepower required for a drilling operation based on the feed rate and tool diameter, which are used to determine the material removal rate (or metal removal rate). Also required is the unit power, which is a material property describing the amount of power required to cut that material. The horsepower at both the spindle and the motor are shown, as well as the spindle torque for a given spindle speed (RPM). The motor horsepower required for the drilling operation can then be compared to the horsepower capability of the machine.

Determine the spindle speed (RPM) and feed rate (IPM) for a turning operation, as well as the cut time for a given cut length. Turning operations remove material from a rotating workpiece by feeding a single-point cutting tool axially, along the side of the workpiece. Calculations use the desired cut diameter, cutting speed, and cutting feed, which should be chosen based on the specific cutting conditions, including the workpiece material and tool material. In some turning operations, the diameter of the workpiece will change so the spindle speed and cutting speed (SFM) must change as well. Typically, values are calculated for a single cut diameter and then either the spindle speed or cutting speed is held constant while the other varies.

Calculate the horsepower required for a turning operation based on the feed rate, depth of cut, and cut diameter, which will determine the material removal rate (or metal removal rate). Also required is the unit power, which is a material property describing the amount of power required to cut that material. The horsepower at both the spindle and the motor are shown, as well as the spindle torque for a given spindle speed (RPM). The motor horsepower required for the turning operation can then be compared to the horsepower capability of the machine.

Calculate the surface roughness for a turning operation based on the tool nose radius and the cutting feed (IPR). Single-point cutting tools used for finishing operations have a rounded front corner, or “nose”, which forms small peaks and valleys in the material as the tool feeds along the rotating workpiece. The height of these surface variations define the surface roughness, which can be measured as an arithmetic average (Ra) or an RMS value.