CMT 309.040.12 Dowel Drill - 5/32" x 30 x 70mm Left-Hand Rotation is a precision-engineered left-hand carbide-tipped boring tool designed for clean, accurate blind-hole drilling in furniture manufacturing, cabinet making, and panel processing applications. Built on a super-strength steel body with a tungsten carbide (HW) cutting head, this 4-flute dowel drill delivers flat-bottom bores with smooth walls in solid wood, chipboard, MDF, laminates, and coated panels. The long-series 70mm overall length makes it well suited for thicker panel stock requiring deeper blind holes, while the PTFE-coated cutter portion resists pitch and glue buildup to extend service life between sharpenings.

Key Features

• HW (tungsten carbide) cutting head on a super-strength steel body - delivers long-lasting edge retention under the high-cycle demands of multi-spindle boring machines and CNC panel processing centers.
• PTFE coating on the cutter portion - repels pitch, resin, and adhesive buildup so the flutes stay clear and cutting performance stays consistent over extended production runs.
• 2 precision-ground negatively set spurs (V2) - score the perimeter of the bore cleanly before the main cutters engage, preventing tearout and producing sharp, chip-free entry points in laminates and coated panels.
• 2 HW precision-ground cutting edges (Z2) - ensure a flat-bottom hole geometry that seats dowels flush and square, which is critical for tight-tolerance joint assembly.
• 4 spiral flutes - evacuate chips efficiently from the bore, reducing heat buildup and keeping the cutting zone clear during continuous drilling cycles.
• Left-hand (LH) rotation - designed specifically for left-hand spindle positions on multi-spindle boring machines and CNC boring centers, ensuring correct cutting geometry and chip ejection direction.
• Precision-balanced centre point - promotes accurate entry location and prevents walking at the start of the bore, which is especially important in high-volume production environments where hole placement tolerances are tight.
• 10x20mm parallel shank with driving flat and length adjusting screw - provides secure, positive engagement in boring machine chucks and allows fine axial positioning for consistent blind-hole depth across all spindles.
• 70mm overall length (long series) - accommodates thicker panel stock and furniture components that require deeper blind holes than standard-series dowel drills can reach.

Why This Product

• Left-hand rotation fills a specific mechanical requirement on multi-spindle boring machines where LH spindles must turn the cutter in the correct direction - using a right-hand drill on an LH spindle would rub rather than cut, making this the functionally correct choice for those positions.
• The negatively ground spurs combined with the HW cutting edges work together to produce clean-entry, flat-bottom dowel holes in laminates and coated panels where surface tearout is a common quality issue.
• At 70mm overall length, this long-series drill reaches depths that standard-series dowel drills cannot, making it the right tool when working with thicker panel stock or furniture components that require deeper dowel pocket placement.
• The PTFE-coated cutter portion and 4-flute chip ejection design support high-cycle production drilling by reducing the adhesive and resin contamination that shortens tool life in furniture and cabinet manufacturing environments.

Specifications

• Manufacturer Part Number: 309.040.12
• Brand: CMT Orange Tools
• Diameter: 4mm (5/32")
• 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 Grind: Negatively ground
• Blade Material: HW (Tungsten Carbide)
• Rotation: Left-Hand (LH)
• Cutter Coating: Black or orange PTFE

Approved Applications

• Blind-hole dowel pocket drilling for dowel joint assembly
• Panel drilling in furniture manufacturing and cabinet making
• Drilling in chipboard, MDF, HDF, hardwood, softwood, plywood, laminates, and coated panels
• Multi-spindle CNC boring machine left-hand spindle positions
• CNC boring center and panel processing center operations
• Boring machines equipped with an adapter or chuck compatible with a 10x20mm parallel shank