Norton 66623399052 Flap Disc 80 Grit Type 29 4 Inch

Product Description

The NORTON 66623399052 is a Type 29 zirconia alumina flap disc designed for aggressive material removal on metal surfaces. It features an 80-grit, medium-grade abrasive with a fiberglass backing that provides flex and durability under load. The conical Type 29 geometry increases surface contact at a work angle, making it well suited for blending, grinding, and finishing on flat and contoured workpieces. Rated at 15,300 RPM, this disc is built for use on standard 4-inch angle grinders and fits a 5/8-inch arbor. It is installed and used by metal fabricators, welders, pipefitters, and general trade professionals working with ferrous and non-ferrous metals.

This flap disc is intended for use on angle grinders in fabrication shops, job sites, and maintenance environments. Its Type 29 design performs best when the grinder is held at a 15- to 25-degree angle to the workpiece, enabling efficient stock removal while leaving a smoother finish than a grinding wheel. The 80-grit zirconia alumina abrasive self-sharpens during use, extending cut life on steel, stainless steel, and other hard metals. Typical applications include weld blending, surface conditioning, and deburring on structural components and pipe.

Key Features

• Type 29 conical flap disc geometry for aggressive grinding at a work angle
• 80-grit zirconia alumina abrasive provides medium-grade cut and finish
• Fiberglass backing delivers flexibility and structural support under load
• 15,300 RPM maximum speed rating for use on standard angle grinders
• 5/8-inch arbor hole fits common 4-inch angle grinder spindles
• Blue disc color for quick visual identification in multi-disc environments

Compatibility

Designed as an OEM-style replacement flap disc for use on 4-inch angle grinders equipped with a 5/8-inch arbor attachment.

Installation Notes

Installation and disc changes must be performed by a qualified operator with the grinder powered off and unplugged or locked out. Inspect the disc for cracks or damage before mounting and ensure the RPM rating of the disc meets or exceeds the grinder's no-load speed. Never exceed the maximum rated speed of 15,300 RPM. Follow ANSI B7.1 and applicable OSHA standards for abrasive wheel mounting and guarding.