Type 1 vs Type 27 vs Type 29 vs Type 28 Grinding Wheels

Grinding wheels are designed with sharp abrasive grains (various abrasive grits) and are used for grinding, cutting, and machining. Since grinding wheels are made of abrasives, they are also known as abrasive wheels.

This abrasive wheel remove excess material from metal, glass, wood, masonry, and concrete. Abrasive wheels are used with various power tools and industrial machines, such as angle grinders and bench grinders. Metal fabricators use different types of grinding wheels for different metalworking applications. Grinding includes Type 1, Type 27, Type 29, and Type 28 grinding wheels.

Type 1 (Straight Grinding Wheel)

Type 1 or straight grinding wheels are the most common and general-purpose abrasive tools made of fiberglass discs/steel rings and fine abrasive grits. These wheels are available in both non-reinforced and reinforced forms. Type 1 grinding wheels are designed for the coarse and fine grinding of hard and soft steel, stainless steel, cast iron, aluminum, bronze, brass, concrete, stone, terrazzo, and ceramic material.

What is a Type 1 Grinding Wheel Used For?

The straight grinding wheel is primarily angle grinders (both electric and hand-held), die grinders, and bench grinder attachments used for grinding and sharpening cutting tools. Aluminum oxide is the most common abrasive grain used in straight grinding wheels. Its strong, inexpensive, and break-resistant feature is perfect for general-purpose grinding and deburring applications.

Type 27 (Depressed Center Grinding Wheel)

Type 27 or depressed center grinding wheels are the most common tool. These metal grinding tools are designed to handle different hard grinding jobs ranging from heavy stock removal to abrasive mixing. Type 27 Grinding Wheels are a renowned grinding tool designed for rough granulation on different materials. These metalworking tools are commonly used in heavy machinery industries and in small hardware workshops. 

What is a Type 27 Grinding Wheel Used For?

Type 27 grinding wheels are a very popular group of general-purpose and specialized abrasive tools intended for rough grinding on a variety of materials. They are commonly used in construction, shipbuilding, metallurgy, foundry, engineering, chemical, and other industries and small workshops.

Read More: Grinding Wheel vs Flap Disc vs Sanding Disc

Type 29 (Flexible Grinding Wheel)

The Type 29 grinding wheel combines an abrasive wheel and a sanding disc. These semi-flexible wheels can aggressively remove material like a grinding wheel while blending and finishing like a sanding disc. These abrasive wheels tend to bend over curved surfaces when grinding, resulting in a smooth finish and gouge-free surface. The stock removal rate is higher than depressed center wheels.

What is a Type 29 Grinding Wheel Used For?

Type 29 wheels are used for grinding and removing weld logs. These wheels are perfect for handling flat and curved surfaces. They can grind cooler. These wheels also have high steel, stainless steel, and aluminum stock removal rates. They are excellent metalworking tools for cutting and finishing a variety of metals at a time. Type 29 grinding wheels are also good for rust removal, deburring, weld grinding, blending, and finishing on contoured and flat surfaces.

Type 28 (Saucer Depressed Center Wheel)

Type 28 grinding wheels are also known as saucer depressed center cutting wheels, used to grind large surfaces and provide excellent finishing and sharpening. Additionally, these wheels also have fiberglass reinforcement. The Type 28 grinding wheel is made from excellent aluminum oxide and provides consistent performance at an affordable price.

Read More: How to Choose the Right Cutting Wheel

What is a Type 28 Grinding Wheel Used For?

The Type 28 grinding wheel is used for stock removal, beveling and weld smoothing. These wheels also have good rigidity and a strong bond for long-lasting cutting power to cut stainless steel and hard and soft carbon steel easily. It is essential to choose the right abrasive wheel to get maximum output. Type 28 saucer wheels are designed with high-quality aluminum oxide for reliable performance at a low cost. Normal-sized, 1/4-inch grinding wheels are perfect for stock removal, weld smoothing, and beveling with a 90-degree right-angle grinder.