CMT Dowel Drill with Countersink - 5/16" x 20 x 57mm, 10x20mm Shank, Left-Hand Rotation by CMT is a precision boring tool engineered for drilling and countersinking in a single pass on boring machines and CNC panel processing equipment. Combining a tungsten carbide (HW) cutting head with a super-strength steel body, this left-hand rotation dowel drill produces clean, flat-bottom holes with a simultaneously formed countersink recess - ideal for bolt head seating, connector recessing, and high-volume panel fabrication. The spiral portion is coated with P.T.F.E. to minimize pitch and adhesive buildup during production runs, keeping the flutes clear and cutting performance consistent.

Key Features

• HW (Tungsten Carbide) Cutting Head - delivers long edge life and stable performance across demanding panel materials including chipboard, MDF, hardwood, plywood, and coated panels, reducing the frequency of tool changes.
• P.T.F.E.-Coated Spiral Flutes - the orange or black anti-friction coating prevents pitch, resin, and glue buildup on the 2 spiral flutes, maintaining clean chip evacuation and consistent cut quality over extended production cycles.
• 2 Precision-Ground Cutting Edges (Z2) - balanced cutting geometry produces smooth bore walls and accurate hole diameters on every pass, minimizing tearout and surface defects on finished panels.
• Negatively Ground Spurs (V2) - 2 negatively sharpened spurs score the material perimeter cleanly before the main cutting edges engage, resulting in crisp, splinter-free entry holes in laminates and coated surfaces.
• Integrated Countersink - drills and countersinks simultaneously in one plunge, eliminating a secondary machining step and increasing throughput on boring centers and multi-spindle machines.
• Precision-Balanced Centre Point - the HW centre point registers accurately on the workpiece surface, preventing wander at entry and ensuring hole placement accuracy across repeat drilling cycles.
• Parallel Shank with Driving Flat and Length Adjusting Screw - the 10x20mm shank locks securely in boring machine spindles, while the length adjusting screw allows precise depth setting to match panel thickness and connector requirements.
• Left-Hand (LH) Rotation - designed specifically for left-hand spindle positions on multi-spindle boring machines and CNC boring centers, ensuring correct chip ejection direction and proper cutting action.

Why This Product

• Combines drilling and countersinking into a single-pass operation - eliminating a secondary tool change or separate countersinking step saves cycle time on high-volume panel processing lines.
• The negatively ground spurs and precision carbide cutting edges work together to produce clean entry and exit surfaces on laminates, coated panels, and hardwood - reducing rejects and rework on finished furniture and cabinet components.
• P.T.F.E. spiral coating actively resists adhesive and pitch buildup that would otherwise degrade cut quality mid-run - making this drill a reliable choice for production environments where consistent results across large batch sizes matter.
• The parallel 10x20mm shank with driving flat and length adjusting screw provides secure tool retention and repeatable depth settings in boring machine spindles, supporting accurate connector and bolt-head recessing across repeated setups.

Specifications

• Manufacturer Part Number: 376.082.12
• Brand: CMT Orange Tools
• Diameter: 5/16"
• Cutting Height: 20mm
• Total Length: 57.5mm
• Shank: 10x20mm
• Rotation: Left-Hand (LH)
• Number of Cutting Edges: 2 (Z2)
• Number of Spurs: 2 (V2)
• Spur Sharpening: Negatively ground spurs
• Blade Material: HW (Tungsten Carbide)
• Spiral Coating: P.T.F.E. (orange or black)

Approved Applications

• Drilling and countersinking in one pass on boring machines and CNC boring centers
• Bolt head and connector recessing in panel components
• Dowel hole preparation in furniture and cabinet panel processing
• High-volume panel fabrication on multi-spindle CNC boring machines