FLEX-HONE GBD31412 Cylinder Hone, 3-1/4 Inch Bore, 120 Grit, Silicon Carbide

FLEX-HONE GBD31412 Cylinder Hone, 3-1/4 Inch Bore, 120 Grit, Silicon Carbide

• The Brush Research GBD31412 Flex-Hone is a heavy-duty cylinder honing tool designed for 3-1/4 inch bore diameter applications. Equipped with 120 grit silicon carbide abrasive, it creates a plateau-style cross-hatch finish ideal for enhancing lubrication retention, reducing leakage, and preparing seals in engine blocks, hydraulic cylinders, and industrial components.
• Features:
  • Bead-style flexible filament design with self-centering and self-aligning action
  • 120 grit silicon carbide abrasive balances peak removal with oil-valley preservation (approx. 35–50 µin Ra)
  • Non-directional plateau cross-hatch pattern ensures consistent sealing surfaces
  • Heavy-duty construction for engine blocks, hydraulic, and industrial bores
• Specifications:
  • Bore Diameter: 3-1/4"
  • Abrasive Material: Silicon Carbide
  • Grit: 120 (Medium)
  • Abrasive Length: 5"
  • Overall Length: 13-1/2"
  • Stem Diameter: 0.31"
  • Recommended Speed: 600–900 RPM
  • Typical Surface Finish: 35–50 µin Ra
  • Applications: Engine blocks, hydraulic cylinders, industrial bores
• The FLEX-HONE GBD31412 can also be referred to as 3-1/4" bore hone, GBD31412 flex hone, silicon carbide cylinder hone, heavy-duty bore brush, and block bore finishing tool.

Brush Research Manufacturing’s GBD-Series Flex-Hones are heavy-duty tools trusted in professional automotive, hydraulic, and industrial settings for delivering reliable plateau-style finishes in medium-large bore applications.

Q: What bore diameter is this hone designed for?
A: The GBD31412 Flex-Hone is engineered specifically for 3-1/4" bore diameter cylinders.

Q: What finish quality does the 120 grit provide?
A: This grit delivers a medium plateau finish of approximately 35–50 µin Ra, ideal for oil retention and sealing surfaces.

Q: Can this hone be used with a handheld drill?
A: Yes—when used with drills or drill presses, maintain speeds between 600 and 900 RPM and use oil-based honing lubricant.

Q: What materials is this hone suitable for?
A: It works effectively on cast iron, mild steel, stainless steel, and other ferrous materials in engine, hydraulic, and industrial applications.

Q: What lubricant should be used?
A: Use oil-based honing lubricant to preserve the abrasive bond and ensure optimal finish quality.