Sanding Belts
  • Red Label Abrasives EdgeCore

    EdgeCore Grinder Belts

  • Sanding Discs
  • Red Label Abra-silk sanding discs

    Abrasilk Foam Sanding Discs

  • by David Kranker October 06, 2020 3 min read

    Quick Summary

    The optimal speed for belt grinders is largely dependent on a number of factors, including type of abrasive grain, grit grade, workpiece material, and more. Generally speaking, a safe speed in most cases is 3,000 surface feet per minute. You can calculate surface feet per minute using the formula SFPM = RPM X .262 X Tool Diameter.

    Topics Covered: 

    When using a belt grinder, running it at the right speed is as important as choosing the correct abrasive. Different workpiece materials need different speeds for ideal belt performance, stock removal rate, and productivity. In this blog, we’ll explain how to calculate the optimal cutting speed for a belt grinder, also known as its surface feet per minute (SFPM).

    What is Surface Feet Per Minute?

    SFPM refers to your belt grinder’s speed in linear feet per minute, or cutting speed. It indicates the relative velocity between the abrasive belt and the surface of the workpiece. The higher the speed of the belt, the higher the cut rate, as more cutting edges appear in the workpiece as the speed increases. With each application, the goal is to run the SFPM as high as possible to increase production while maintaining minimal heat generation.

    Different materials run better at different SFPMs. The formula below can be used to calculate cutting speed for working on various types of workpieces.

    SFPM = RPM X .262 X Tool Diameter 

    For example, if you have a 2 x 72 belt grinder with an 1800 RPM motor with a 4” drive wheel, the formula would look like this:

    (1800 x .262) x 4” = 1886

    Optimal belt speed can vary slightly depending on the type of abrasive grain and grit grade you’re using, but in general, this formula should get your operations near the ideal range for high cut rates.

    Recommended Surface Speeds By Material

    Like grain type and grit grade, the material you’re processing will also affect recommended surface speed. The greater the density of the material, the harder it will be and the higher the abrasive speed will generally need to be to be effective. Recommended surface speeds by material can be found in the table below. 

    Material to be Processed 

    Surface Speed (Feet per Minute)


    960 - 2700

    Glass, Ceramics, & Stone

    1560 - 2700

    Lacquers & Varnshies 

    1560 - 2940

    Hard & Hardened Steel

    1560 - 2940

    Plastic & Rubber

    1920 - 3540

    Titanium & Titanium Alloys

    1920 - 4920


    2940 - 4920

    Aluminum & Zinc

    3540 - 5880

    Stainless Steel, Tool Steel, & High Speed Steel

    3540 - 5880

    Copper & Brass 

    4920 - 6840

    Cast Iron & Carbon Steel

    4920 - 8820

    Why SFPM is Important

    Sanding is an art of balance. Running your belt sander too fast can ruin the temper of metals. Higher speeds can also burn out the bearings on smaller contact wheels.

    Speed becomes more important when you're finish grinding. You'll want to make sure you're running your grinder at a slow enough speed to be able to grind with precision. 

    If you are new to belt grinder use or have questions about the appropriate SFPM for a material you have never worked with, contact an experienced abrasives manufacturer for guidance. Although the formula for SFPM is generally valid, variables like the following also have an impact:

    • The material you will be grinding
    • The type of abrasive you are using (e.g. ceramic, zirconia, A/O)
    • The grit of the sanding belt. Higher grits are recommended for polishing while lower grits are used to remove stock and provide more definition to the workpiece.

    A reputable specialist can make an informed recommendation based on intended use and even provide you with the right abrasive for the job.

    Contact an Abrasive Specialist

    At Red Label Abrasives, we custom-manufacture premium quality sanding belts for various types of belt grinders and can provide you with information about how you can increase the working life of your machine/belts. Red Label Abrasives has been family-owned for over 35 years. We take great pride in offering exceptional customer service and unrivaled technical support. If you would like to place an order or you have more questions, please call 844-824-1956 or fill out a contact form.

    Also in The Daily Grind

    Work Sharp Combo Knife Sharpener Review - Red Label Abrasives
    Work Sharp Combo Knife Sharpener Review

    by David Kranker September 27, 2023 6 min read

    Read More
    Grinding Stainless Steel: How to Grind & Finish Stainless Steel - Red Label Abrasives
    Grinding Stainless Steel: How to Grind & Finish Stainless Steel

    by David Kranker September 25, 2023 10 min read

    Read More
    How To Make A Knife From A File - Red Label Abrasives
    How To Make A Knife From A File

    by David Kranker August 31, 2023 12 min read

    Read More


    David Kranker is a writer and creative maker who has been covering the abrasive and knife-making industries on the Red Label Abrasives Blog since 2020. David spends his time continually researching sanding and bladesmithing to provide readers with the latest and greatest information. In his free time, David utilizes abrasives for many different home and auto projects at his home in Delton, MI.