CMT 316.120.12 Countersink for 4 Flute Drills by CMT is a precision-engineered left-hand rotation countersink designed to work in tandem with 4-flute boring systems, delivering a clean 45 deg. chamfer and a 15/32" (20mm) cutting diameter in a single operation. Built from HW (tungsten carbide) material, this countersink is suited for use on CNC boring centers and multi-spindle machines where left-hand tooling setups demand accuracy, consistency, and reliable seating geometry with every cycle.

Key Features

• HW (Tungsten Carbide) Construction - delivers long-lasting edge retention and resistance to wear, reducing tool change frequency in high-cycle production environments.
• 45 deg. Cutting Angle - produces a precise chamfer geometry that ensures consistent screw and fastener seating across repeated operations, minimizing the need for rework.
• Left-Hand (LH) Rotation - engineered specifically for left-hand spindle configurations, ensuring proper chip evacuation and cutting performance in LH boring machine setups.
• 20mm (15/32") Cutting Diameter - provides a countersink profile sized to accommodate standard hardware and joinery fasteners used in panel and wood component production.
• 12mm Bore Diameter - allows direct mounting onto 12mm spindle noses or adapters common to CNC boring centers, enabling quick and secure tool installation.
• 2-Tooth Cutting Configuration - balances cutting efficiency with smooth finish quality, helping reduce vibration and surface chatter during countersinking passes.
• Compact 15mm Total Length - minimizes spindle protrusion and allows use in tight multi-spindle head configurations where clearance between adjacent tools is limited.

Why This Product

• The left-hand rotation design makes this countersink the correct choice for LH spindle positions on multi-spindle CNC boring machines - pairing it with a right-hand tool in an LH spindle would produce incorrect geometry and poor finish results.
• The 45 deg. carbide-tipped countersink angle is matched to widely used European hardware standards, making it well-suited for cabinet and furniture production workflows that rely on precise fastener seating depth.
• At 15mm total length, this tool integrates into compact boring head arrangements without crowding adjacent spindles, supporting dense multi-spindle configurations found on panel processing equipment.
• Tungsten carbide (HW) construction gives this countersink the durability to withstand the high feed rates typical of 4-flute drilling operations, maintaining cutting accuracy across long production runs.

Specifications

• Manufacturer Part Number: 316.120.12
• Brand: CMT Orange Tools
• Cutting Diameter: 20mm (15/32")
• Bore Diameter: 12mm
• Total Length: 15mm
• Cutting Angle: 45 deg.
• Number of Teeth: 2
• Rotation: Left-Hand (LH)
• Blade Material: HW (Tungsten Carbide)

Approved Applications

• Multi-spindle CNC boring machines with left-hand spindle positions
• CNC boring centers using 12mm spindle noses or chuck adapters
• Panel processing centers requiring countersink operations on cabinet and furniture components
• Boring machines with adapter or chuck setups configured for LH tooling
• Chipboard, MDF, HDF, plywood, laminates, coated panels, hardwood, and softwood workpieces