Brush Research Mfg. BUS314 Knotted Cup Brush 3 Inch Carbon Steel

Product Description

The BRUSH RESEARCH MFG. BUS314 is a knotted cup brush designed for aggressive surface preparation, weld cleaning, rust removal, and scale removal on metal workpieces. Built with carbon steel wire at 0.014 inches in diameter, the knotted fill construction delivers concentrated, high-impact abrasive action that outperforms crimped-wire designs on tough scale and heavy mill scale. The brush runs up to 14000 RPM and fits a standard 5/8-11 threaded arbor, making it compatible with most angle grinders used in metal fabrication, welding, and HVAC ductwork work. The single-row configuration and 7/8-inch trim length provide controlled, focused contact across the work surface.

This cup brush is suited for both residential and commercial metalworking applications, including weld prep, post-weld cleanup, pipe deburring, and surface conditioning ahead of coating or painting. It is commonly used by welders, pipefitters, HVAC installers, and general fabricators working with structural steel, pipe, and sheet metal. The 3-inch brush diameter covers moderate surface areas efficiently without sacrificing the bite that knotted wire provides on heavily oxidized or contaminated metal.

Key Features

• Knotted carbon steel wire fill for aggressive material removal on rust, scale, and weld spatter
• 0.014-inch wire diameter provides stiff, durable bristle action
• 14000 maximum RPM rating for use with standard angle grinders
• 5/8-11 threaded arbor hole fits most common angle grinder spindles
• Single-row construction for focused, controlled surface contact
• 7/8-inch trim length maintains consistent wire tension throughout the brush life

Compatibility

Designed for use with angle grinders equipped with a 5/8-11 threaded arbor. Verify grinder RPM rating meets or exceeds 14000 RPM before mounting.

Installation Notes

Installation should be performed by a qualified tradesperson familiar with angle grinder accessories and ANSI B7.2 safety standards for power brushes. Always confirm the grinder spindle speed does not exceed the 14000 RPM rating marked on the brush before use. Wear appropriate PPE including a face shield and leather gloves, as wire bristles can shed under load. Thread the brush firmly onto the 5/8-11 arbor and ensure it is fully seated before powering on the tool.