40 Grit Alumina Zirconia (Blue) Sanding, 4 in. Wide x 24 in. Long

Alumina Zirconia (Blue) Sanding / Planing Belt

Built for heavy stock removal and demanding applications.

These belts are designed for aggressive material removal. They perform well when grinding stainless steel, spring steel, titanium, and other hard steels, and they are also an excellent choice for wood dimensioning. They can also be used for heavy stock removal on plastic, rubber, glass, stone, and concrete products.

Specifications

• Alumina Zirconia grain for aggressive cutting and long life
• YX-weight backing with a lighter-weight polyester construction
• Closed coat for maximum abrasive coverage
• Resin-to-resin bond for durability
• Suitable for wet or dry use
• Sold individually

Alumina Zirconia (AZ)

Alumina Zirconia combines the best characteristics of Aluminum Oxide (AO) and Silicon Carbide (SC), creating a grain that is both durable and friable. Like AO, its primary ingredient is bauxite. Like SC, it fractures during use to expose fresh cutting edges. However, unlike SC, AZ typically requires machine pressure to fracture properly. If enough pressure is not applied, the abrasive can glaze over, reducing cutting efficiency and belt life.

When used correctly, AZ provides an excellent balance of long life and consistently sharp cutting action. It is commonly used where high removal rates are important, including wood planing, heavy metal grinding, and other dimensioning applications. Because it is more expensive to produce than standard abrasive grains, it delivers the best value in coarser grits, typically from 24 to 60, where aggressive removal is the goal.

Cloth Backing

There are three basic weights of cloth backing: J, X, and Y. J and X are cotton backings. J-weight backing offers a slight degree of conformability and is best used where some flexibility to the workpiece is needed in belts or sheets. X-weight backing is a heavier cotton material and serves as an all-purpose backing for a wide variety of sanding belt applications, including portable belts, intermediate belts, and wide belts.

Y-weight backings are made from 100% polyester, or in some cases, a 60/40 polyester-cotton blend. They are designed for flat, heavy-duty dimensioning, high-heat applications, and rough sanding conditions. J and X backings are also available in more flexible versions called J-Flex (JF) and X-Flex (XF). J-Flex is commonly used for pump sleeves and mold sanding belts, while X-Flex is often used for slack belt operations.

Y-weight backings are not flexed, but they are available in lighter and heavier polyester versions. YX indicates a lighter-weight polyester backing, while Y and YY indicate heavier-weight polyester backings. In general, coarser grits such as 24 to 50 or 60 are more often paired with heavier polyester backings, while finer grits such as 80 to 120 are more commonly paired with lighter polyester backings.

Cotton backings are not naturally waterproof unless they have been chemically treated. If a cotton belt is waterproof, the backing will usually be marked as waterproof, W/D, or WP. If no such marking appears, the belt should not be used with water, as the backing may stretch. Oil may sometimes be used as a lubricant if it is suitable for the application.

Polyester backing, on the other hand, is naturally waterproof and typically does not need special marking to indicate that property. In addition to being waterproof, polyester is also tear-resistant and well-suited for shock, heavy-duty sanding, and wet grinding applications. That is why polyester backings are commonly used in rough and demanding environments.