Norton 66254461167 Flap Disc 4.5 in Type 29 40 Grit

Product Description

The NORTON 66254461167 is a Type 29 zirconia alumina flap disc engineered for aggressive material removal on steel surfaces. The disc measures 4.5 inches in diameter and mounts via a 5/8-11 threaded arbor hole, making it compatible with standard right-angle grinders. At 40 grit, it falls in the coarse grade range, suited for heavy stock removal, weld blending, and surface conditioning. The fiberglass backing plate provides rigid support while keeping overall weight low, and the blue-colored flaps are rated to a maximum of 13,300 RPM. This disc is part of the Norton R860 series.

This flap disc is intended for use on steels in both fabrication shop and field environments. Typical applications include weld seam removal, deburring, and surface preparation prior to coating or finishing. The Type 29 conical flap arrangement increases surface contact on flat and slightly contoured workpieces compared to a flat Type 27 disc, making it effective for aggressive grinding at lower angles. It is commonly used by metal fabricators, ironworkers, pipefitters, and maintenance technicians.

Key Features

• Type 29 conical design for increased surface contact and aggressive grinding at low angles
• 40 grit coarse grade for heavy stock removal and weld blending on steel
• Zirconia alumina abrasive material for durability and consistent cut rate
• Fiberglass backing for rigid support and reduced disc flex
• 5/8-11 threaded arbor hole fits standard right-angle grinder spindles
• 13,300 RPM maximum speed rating

Compatibility

Designed for use on steels with standard right-angle grinders equipped with a 5/8-11 threaded spindle. Fits grinders accepting 4.5-inch Type 29 flap discs.

Installation Notes

Installation is performed by threading the disc directly onto a 5/8-11 grinder spindle — no wrench or backing pad is required. Before mounting, confirm the grinder's no-load RPM rating does not exceed the disc's 13,300 RPM maximum. Always inspect the disc for damage before use and ensure the grinder guard is in place. Wear appropriate PPE including face shield, gloves, and hearing protection during operation.