Brush Research Mfg. BC64M320BC Flexible Cylinder Hone

Product Description

The BRUSH RESEARCH MFG. BC64M320BC is a flexible cylinder hone designed for precision bore finishing and surface conditioning in tight cylindrical passages. Built with boron carbide abrasive at 320 grit extra fine grade, this tool is suited for controlled material removal and surface refinement in bores down to 0.236 inches minimum and up to 0.25 inches maximum. The overall length is 8 inches with a 1.5-inch abrasive length and a shank diameter of 0.112 inches. Machinists, tool-and-die workers, and maintenance technicians use this hone in drill press, lathe, or hand-held rotary tool applications where rigid honing tools cannot reach.

This hone is intended for use on medium to high carbon steels, heat-treated steels up to 50 Rc, and titanium. Its flexible design allows the abrasive balls to follow the contour of the bore, making it well suited for deburring, removing light corrosion, and achieving a consistent crosshatch finish in small-diameter cylinders. Typical applications include hydraulic valve bores, small pneumatic cylinders, precision instrument bores, and similar confined cylindrical work where surface finish quality is critical.

Key Features

• Boron carbide abrasive at 320 grit extra fine grade for controlled, fine surface finishing
• Maximum bore diameter of 0.25 inches with minimum bore entry at 0.236 inches
• Abrasive length of 1.5 inches provides consistent contact across short bore depths
• 8-inch overall length allows reach into recessed or deep bore locations
• 0.112-inch shank diameter fits standard collets and rotary tool chucks
• Rated to 1200 RPM maximum for safe operation in variable-speed rotary tools

Compatibility

Suitable for finishing and honing small-diameter cylindrical bores in medium to high carbon steels, heat-treated steels up to 50 Rc, and titanium. Fits standard rotary tool collets and drill press chucks accepting a 0.112-inch shank.

Installation Notes

Secure the shank firmly in a compatible collet or chuck before operation and verify the setup does not exceed the 1200 RPM maximum speed rating. Always wear appropriate eye protection and apply a compatible honing fluid or cutting oil to the bore during use to control heat and extend abrasive life. Inspect the abrasive balls for uniform wear before each use and replace the tool if balls are missing or unevenly worn. Ensure the workpiece is properly fixtured to prevent movement during honing.