Grinding wheels are much like sandpaper. Depending on the task, there are many different types of grinding wheels, and each is suited for a particular task or tool. Grinding and cut off wheels from manufacturers like United Abrasives grinding wheels are designed for use in construction and metal trades. Surface grinding wheels are made from different materials and are more likely to be found on a stationary bench grinder or blade-sharpening tool than on a portable cut off tool. Below is a non-comprehensive list that describes the major categories of abrasive and surface grinding wheels.
Woven, Silicon Carbide Disposable Production Grinding Wheels.
Seen most often on 4 or 5-inch handheld grinding tools, these tough and durable abrasive wheels are the workhorse of the steelworkers and metal fabricators industry. Their woven silicon carbide materials is harder than ferrous steel, and will quickly and efficiently cut through steel, or grind off welding slag to leave a clean joint. Metalworking contractors use these 4 ½, 5 and 6-inch handheld grinding tools in the same way carpenters use their power saws and painters their paintbrushes.
The silicon carbide wheels are inexpensive and are designed as a disposable abrasive. As the wheel cuts or grinds steel, it loses some of its surfaces and abrasive characteristics. When the wheel is too small to be used effectively, the contractor replaces it with a new disk.
Fast Grinding Disks
Fast grinding abrasive disks, including aluminum oxide grinding wheels and zirconium grinding wheels, have a higher abrasive rating than other disks. These tools are designed for quick removal of surface imperfections on steel fabrications. Because of their highly abrasive rating, they are unsuited for applications where a smooth cut edge is desired.
Hard Edge Disks
Hard-edge grinding wheels by United Abrasives are impregnated with ceramic to create an even harder cutting edge. The hard edge disks are less abrasive than the fast grinding disks, but they last much longer. Hard-edge disks are suited for high carbon steels and stainless steel.
Soft Bond Disks
United Abrasive Soft Bond abrasive disks are designed to clear material from a work surface without becoming loaded with metal dust or ferrous debris. Soft bond disks will deteriorate faster than the disks listed above, but they are perfect for softer materials such as copper, brass, bronze, or other soft metals.
Surface grinding wheels are manufactured from composite stone abrasives rather than the fast cutting silicon carbide used in cutting and grinding wheels listed above. These wheels feature a different grain structure than the silicon carbide disk. These disks are manufactured for final preparation of a surface, or sharpening the edge of digging and cutting tools rather than removing metal from welded fabricated steel. Surface grinding wheels are more likely to be found on a stationary bench grinder than on a portable cut off tool.
Surface grinding wheels are also available in different abrasive strengths. Like sandpaper, disks that are more abrasive will remove material quickly, while the finer disks are more suited for finish work, such as putting a finely honed edge on a knife.
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