Diamond and CBN Wheel Speeds

How Fast Should I Be Running My Wheel?

Wheel speed is measured by surface feet per minute (SFPM) and calculated by using the diameter of the wheel and spindle speed of your machine, which can be measured in meters/second (m/s) or revolution per minute (RPM).

A safe SFPM recommendation for Resin Bond wheels is 5,500 SFPM. However, there are other factors that can cause you to have to run a little faster or slower, such as whether or not you are using coolant.

The SFPM can cause a wheel to act softer or harder than usual, depending on how low or high it is.  If the wheel seems to be losing its edge too quickly, you may need to speed up the wheel.  If it seems it is not cutting at all, you may need to slow it down.

These variables should be taken into consideration when determining the life and effectiveness of the wheel.


Eagle Superabrasives offers a phone app that can assist you in determining what SFPM you are running. You can enter the diameter of your wheel (in millimeters or inches) and the spindle speed you are running at (RPMs or m/s) to calculate your SFPM.

Below is a quick reference chart to give you a range of what speed your wheel should be running.  This chart is a guideline, not an absolute.

(Note speeds indicated are Surface Feet Per Minute and Meters/Second Not RPM)