Brush Research Mfg. BC7M32 Flexible Cylinder Hone 320 Grit

Product Description

The BRUSH RESEARCH MFG. BC7M32 is a flexible cylinder hone designed for fine finishing and surface conditioning inside small-diameter bores. Constructed with silicon carbide abrasive in an extra fine 320 grit rating, this tool delivers consistent material removal on mild steel, stainless steel, and cast iron. The hone features a 2-inch abrasive length and an overall length of 8 inches, with a shank diameter of 0.125 inches for compatibility with standard drill chucks and flexible drive tools. Maximum operating speed is 1,200 RPM. Machinists, engine rebuilders, and precision fabricators use this tool to deglaze, finish, and restore bore geometry without aggressive stock removal.

This hone is suited for small-bore applications where a maximum bore diameter of 0.276 inches is required. Typical uses include finishing hydraulic cylinders, pneumatic bores, small engine cylinders, valve guides, and precision machined components. The flexible design allows the abrasive stones to conform to the bore wall, producing a consistent crosshatch pattern that promotes proper seating and lubrication retention. It is used in job shops, engine rebuild facilities, and precision maintenance environments.

Key Features

• 320 grit silicon carbide abrasive rated extra fine for finish honing
• Maximum bore diameter of 0.276 inches suitable for small precision bores
• 2-inch abrasive length provides adequate contact in short and through bores
• 8-inch overall length allows reach into recessed or deep bore locations
• 0.125-inch shank diameter fits standard drill chucks and flexible shaft tools
• Compatible with mild steel, stainless steel, and cast iron workpieces
• Maximum operating speed of 1,200 RPM for controlled finish work

Compatibility

Designed for use in bores up to 0.276 inches in diameter across mild steel, stainless steel, and cast iron applications. Confirm bore diameter and material compatibility before use.

Installation Notes

This tool is installed in a variable-speed drill or flexible shaft drive by inserting the 0.125-inch shank into the chuck and tightening securely. Do not exceed 1,200 RPM during operation. Apply cutting fluid or honing oil to the bore and abrasive stones before use to extend abrasive life and improve surface finish. Ensure the workpiece is securely fixtured before beginning the honing operation.