GB 3-3/4" (89mm) Brake Cylinder Flex-Hone 320SC Grit - Brush Research

The Brush Research GB 3-3/4" (89mm) Brake Cylinder Flex-Hone is a professional-grade honing tool engineered for precise bore finishing in demanding automotive and industrial settings. This tool creates a controlled plateau finish and the essential cross-hatch pattern required for optimizing sealing, improving oil retention, and extending component life in various hydraulic and pneumatic systems. It is designed to meet the rigorous demands of professional technicians seeking reliable performance and consistent results.

Key Features

• Optimal Bore Range: With a 3-3/4" (89mm) nominal diameter, this Flex-Hone is suited for reconditioning larger brake and wheel cylinders, as well as other bores within the 3.50"–3.90" range, making it ideal for trucks, heavy-duty, and industrial equipment.
• Flexible, Self-Centering Design: Abrasive globules on flexible nylon filaments conform to minor bore irregularities, ensuring even pressure and a uniform finish without requiring complex fixturing.
• 320SC Silicon Carbide Abrasive: Utilizing a medium-fine cut 320 grit silicon carbide abrasive, this tool effectively deglazes and refines cast iron and mild steel cylinders, promoting proper seal and piston ring seating.
• Controlled Plateau Finish: Generates the critical cross-hatch pattern necessary for effective oil film control, reduced glazing, and improved seal performance in brake, hydraulic, and pneumatic components.
• Durable Professional-Grade Construction: Designed for daily use in demanding automotive, fleet, and industrial maintenance environments, this tool is compatible with handheld drills or machine tools when operated at low RPM.

Applications

• Deglazing and reconditioning brake and wheel cylinders on light-, medium-, and heavy-duty vehicles.
• Refinishing hydraulic and pneumatic cylinder bores to ensure reliable piston and seal operation.
• Surface preparation of small engine and equipment cylinders prior to ring or seal replacement.
• Preparing bores for new seals, bushings, or pistons where a controlled plateau finish is critical for optimal performance.
• Deburring cross-drilled holes, port radiusing, and edge blending in various components.

Specifications

• Manufacturer: Brush Research Manufacturing (BRM)
• Model: GB33432
• Nominal Diameter: 3-3/4" (89mm)
• Abrasive: Silicon Carbide (SC)
• Grit: 320 grit