Surface Footage Calculator

Formula

The formula to calculate the Surface Footage (SF) is:

\[ SF = \frac{\pi \times D \times RPM}{12} \]

Where:

\( SF \) is the surface footage (feet per minute).
\( D \) is the diameter of the workpiece (inches).
\( RPM \) is the revolutions per minute of the workpiece.

What is Surface Footage?

Surface footage is a measure of the linear distance that a point on the circumference of a rotating object travels in one minute. It is a common metric used in machining to help determine the cutting speed of a tool as it interacts with a workpiece. Proper calculation of surface footage is crucial for achieving desired machining results and extending the life of cutting tools.

Example Calculation

Consider an example where:

Diameter of Workpiece (D): 4 inches
Revolutions Per Minute (RPM): 1500

Using the formula to calculate the Surface Footage:

\[ SF = \frac{\pi \times 4 \times 1500}{12} = 1570.80 \text{ feet per minute} \]

This means that the surface footage for this example is 1570.80 feet per minute.