Brush Research Mfg. BC11M32 Flexible Cylinder Hone 320 Grit

Product Description

The BRUSH RESEARCH MFG. BC11M32 is a flexible cylinder hone designed for precision bore finishing in metalworking and engine rebuilding applications. This tool uses silicon carbide abrasive balls mounted on flexible filaments to conform to the bore surface and remove light material consistently. Rated at 320 grit, it falls in the extra fine grade range, making it suited for final finishing passes rather than aggressive stock removal. The overall length is 8 inches, with an abrasive length of 2 inches and a shank diameter of 0.14 inches for use in standard drill chucks or flexible shaft tools. Maximum operating speed is 1,200 RPM.

This hone is used in machine shops, engine rebuild shops, and maintenance facilities where bore surface finish is critical. It is suited for working mild steel, stainless steel, and cast iron bores up to 0.43 inches in diameter. Typical applications include small engine cylinders, hydraulic bores, valve guides, and precision housings where a consistent crosshatch or finished surface is required before assembly.

Key Features

• 320 grit silicon carbide abrasive - extra fine grade for finish honing passes
• Maximum bore diameter of 0.43 inches (11 mm) for small-bore applications
• Flexible filament design conforms to bore geometry without rigid tooling setup
• Compatible with mild steel, stainless steel, and cast iron materials
• 8-inch overall length provides reach into deeper bore configurations
• Maximum operating speed of 1,200 RPM for use with standard electric drills or flexible shaft tools

Compatibility

Designed for use in bores up to 0.43 inches in diameter across mild steel, stainless steel, and cast iron workpieces. Suitable as a general-purpose finish honing tool for small-bore metalworking and engine service applications.

Installation Notes

This tool is installed in a standard drill chuck or flexible shaft machine and operated at or below the rated maximum of 1,200 RPM. Use with an appropriate honing oil or cutting fluid to extend abrasive life and maintain surface finish quality. Keep the tool moving in and out of the bore during operation to produce an even crosshatch pattern and prevent uneven wear. Inspect abrasive balls for wear before each use and replace the hone when abrasive material is depleted to avoid workpiece damage.