FLEX-HONE GBD40012 Cylinder Hone, 4 Inch Bore, 120 Grit, Silicon Carbide (Mild/Stainless/CI)
- The Brush Research GBD40012 Flex-Hone is a professional-grade cylinder honing tool designed for 4 Inch bore applications. Featuring 120 grit silicon carbide abrasive, this tool delivers a plateau-style, non-directional finish ideal for improving lubrication retention and sealing performance in mild steel, stainless steel, cast iron, and other softer ferrous materials.
- Features:
- Self-centering, self-aligning, and wear-compensating design for uniform contact and consistent results
- 120 grit silicon carbide abrasive removes high peaks while preserving surface valleys for oil retention
- Produces a plateau-style cross-hatch finish that minimizes oil leakage and enhances seal performance
- Heavy-duty construction suitable for engine blocks, hydraulic cylinders, and industrial bores
- Made in the USA by Brush Research Manufacturing
- Specifications:
- Bore Size: 4"
- Abrasive: Silicon Carbide
- Grit: 120 (Medium)
- Hone Length: 6"; Overall Length: 13.5"
- Stem Diameter: 0.31"
- Recommended RPM: 350–600 (maximum 600 RPM)
- Typical Surface Finish: ~35–50 µin (0.9–1.4 µm)
- Tool Weight: Estimated 1.4 lb
- Application: Mild steel, stainless steel, cast iron, and softer ferrous materials
- Country of Origin: USA
- The FLEX-HONE GBD40012 can also be referred to as 4" flex hone, cylinder hone, silicon carbide hone, plateau hone, and engine block hone.
Brush Research Manufacturing has over 60 years of experience producing innovative surface finishing tools. Their Flex-Hone line is recognized globally for delivering consistent, high-quality finishes in automotive, hydraulic, and industrial applications.
Q: What materials is the GBD40012 designed for?
A: It is ideal for mild steel, stainless steel, cast iron, and other softer ferrous metals commonly found in engine and hydraulic components.
Q: Can I use this hone with a handheld drill?
A: Yes, as long as the drill operates within the recommended 350–600 RPM range and proper lubrication is used.
Q: What finish does the 120 grit provide?
A: 120 grit creates a medium plateau finish, ideal for prepping sealing surfaces and enhancing oil retention without aggressive material removal.
Q: How long does the tool typically last?
A: With appropriate use and lubrication, the hone can be reused across multiple bores before needing replacement.
Q: What lubricant should I use with this tool?
A: Use standard honing oil or other oil-based lubricants. Avoid solvents, as they may weaken the abrasive bond.
