Merit Abrasives 66623355604 Fiber Disc 4-1/2 in 60 Grit

Product Description

The MERIT ABRASIVES 66623355604 is a ceramic alumina fiber disc designed for aggressive material removal on metal, weld seams, and hard surfaces. It measures 4-1/2 inches in diameter with a 7/8-inch arbor hole and carries a coarse 60-grit rating backed by a resinoid bond. The ceramic abrasive grain self-sharpens as it cuts, maintaining a consistent cut rate throughout the disc life. Rated at 11000 RPM maximum, this disc is engineered for use on standard angle grinders. The fiber backing provides rigidity and heat resistance, keeping the disc stable under load. HVAC fabricators, pipefitters, ironworkers, and sheet metal mechanics are the typical end users.

This disc is suited for weld grinding, surface prep, and deburring on ferrous and non-ferrous metals in industrial, commercial, and field service environments. The 4-1/2-inch size fits the most common angle grinder platform in trade work. Coarse 60 grit makes it the right choice for stock removal and leveling rather than finishing passes. It mounts via the 7/8-inch arbor hole and requires a compatible rubber or fiberglass backing pad for proper support during use.

Key Features

• Ceramic alumina abrasive grain for high cut rate and extended disc life
• Coarse 60 grit for aggressive stock removal and weld grinding
• 11000 RPM maximum speed rating for standard 4-1/2-inch angle grinders
• Resinoid bond holds grain firmly under heavy pressure and heat
• Fiber backing provides rigidity and stability on flat and contoured surfaces
• 7/8-inch arbor hole fits the most common angle grinder spindle size

Compatibility

Designed as an OEM-style replacement or direct-fit abrasive disc for 4-1/2-inch angle grinders accepting a 7/8-inch arbor hole and operating at or below 11000 RPM.

Installation Notes

Installation and use should be performed by qualified personnel familiar with angle grinder safety practices and applicable ANSI B7.1 grinding wheel safety standards. Always inspect the disc for cracks or damage before mounting and never exceed the 11000 RPM maximum speed rating. Mount the disc using a proper backing pad matched to the disc diameter, and ensure the arbor nut is secure before operating. Wear appropriate PPE including a face shield, gloves, and hearing protection during grinding operations.