CMT 309.080.12 Dowel Drill 5/16" x 43 x 70mm Left-Hand by CMT is a precision-engineered, carbide-tipped boring tool built for accurate blind-hole drilling in furniture manufacturing, cabinet making, and panel processing applications. Designed for left-hand rotation, this 5/16" diameter dowel drill features a hardened tungsten carbide (HW) cutting head, 4 spiral flutes, and negatively ground spurs that produce clean, flat-bottom holes in chipboard, MDF, hardwood, softwood, plywood, and coated panel stock. The long-series 70mm overall length accommodates deeper blind holes in thicker panel assemblies, making it a reliable choice for multi-spindle CNC boring machines and panel processing centers alike.

Key Features

• Tungsten carbide (HW) cutting head with 2 precision-ground cutting edges (Z2) - delivers consistent bore quality and extended tool life across high-volume production runs in solid wood, chipboard, MDF, and laminates.
• 2 negatively ground spurs (V2) - shear the wood fibers at the perimeter of the hole before the main cutting edges engage, producing clean bore walls and sharp hole edges with no tearout or fraying on coated and laminated surfaces.
• 4 spiral flutes - evacuate chips efficiently during drilling, reducing heat buildup, preventing clogging, and maintaining consistent cut quality even during continuous operation.
• PTFE coating on the cutter portion (black or orange) - resists pitch and adhesive buildup on the flutes, minimizing cleaning downtime and keeping the tool cutting freely in resin-heavy materials like chipboard and coated panels.
• Precision balanced centre point - ensures the drill registers accurately on the panel surface at the start of each bore, reducing wandering and maintaining tight hole-location tolerances required for dowel joinery.
• Super-strength steel body - provides the rigidity and shock resistance needed to withstand the demands of multi-spindle boring machinery without flexing or deflecting during the cut.
• Parallel shank (10x20mm) with driving flat and length adjusting screw - secures positively in spindle chucks or boring head adapters, allowing precise depth setting and preventing rotation slip during left-hand operation.
• Left-hand (LH) rotation - matches the spindle direction of left-hand boring positions on multi-spindle boring machines, ensuring correct cutting geometry and optimal chip ejection in those stations.
• Long-series design - 70mm overall length with 43mm cutting height - reaches deeper into the panel than standard-series bits, accommodating thicker stock and deeper blind holes without the need for extension adapters.

Why This Product

• Purpose-built for left-hand spindle stations - many multi-spindle boring machines include both right-hand and left-hand spindles. Using a correctly handed drill, like this LH model, ensures the cutting geometry works with the spindle rotation rather than against it, protecting both the tool and the workpiece surface finish.
• Negatively ground spurs eliminate tearout on coated and laminated panels - furniture and cabinet panels are often faced with melamine, HPL, or veneer that tears easily with blunt tooling. The V2 negatively ground spur design severs surface fibers cleanly before the bore opens, preserving the decorative face of the panel.
• Long-series 70mm length opens up deeper panel applications - when working with thicker carcass panels or stacked assemblies, the 43mm cutting height and 70mm overall length provide the reach needed for deep blind holes without tool changeovers or adapters.
• PTFE-coated flutes reduce maintenance in production environments - in cabinet shops and furniture factories running chipboard and MDF continuously, resin and adhesive accumulation on tool flutes is a routine problem. The PTFE coating sheds these contaminants, keeping the tool cutting cleanly between sharpenings and reducing unplanned downtime.

Specifications

• Manufacturer Part Number: 309.080.12
• Brand: CMT Orange Tools
• Product Type: Dowel Drill
• Diameter: 5/16"
• Cutting Height: 43mm
• Total Length: 70mm
• Shank: 10x20mm parallel shank with driving flat and length adjusting screw
• Number of Flutes: 4
• Number of Cutting Edges: 2 (Z2)
• Number of Spurs: 2 (V2)
• Spur Sharpening: Negatively ground spurs
• Blade Material: HW (Tungsten Carbide)
• Rotation: Left-hand (LH)
• Coating: PTFE (black or orange) on cutter portion

Approved Applications

• Drilling blind holes for dowel connections in furniture and cabinet panels
• Panel boring on multi-spindle CNC boring machines
• Panel processing on CNC boring centers and panel processing centers
• Boring on machines equipped with an adapter or chuck
• Furniture manufacturing and cabinet making
• Drilling in solid wood (hardwood and softwood), chipboard, MDF, HDF, plywood, laminates, and coated panels