Kennametal 3894812 Screw Machine Drill Bit 5.56mm Carbide

Product Description

The KENNAMETAL 3894812 is a stub-length (screw machine length) solid carbide drill bit designed for high-precision drilling in demanding machining applications. Built to DIN 6535 standards, it features a 5.56 mm (0.2189 inch) cutting diameter with a 180-degree flat-bottom point geometry, making it well suited for flat-bottomed holes and controlled-depth drilling. The two-flute, right-hand spiral design promotes efficient chip evacuation. The bright/uncoated finish is standard for applications where coating additives are not required. Machining professionals and tool-and-die technicians use this bit where tight tolerances and stub-length rigidity are critical.

This drill bit fits typical CNC machining centers, drill presses, and screw machine setups used in precision manufacturing environments. The straight cylindrical shank at 6.00 mm (0.2362 inch) diameter seats securely in standard collets and chucks. With a maximum drilling depth of 20.00 mm (0.7874 inch) and a flute-to-diameter ratio of 3xD, it is intended for shallow-to-moderate depth holes where rigidity and runout control matter. It is commonly used in metalworking shops, production machining, and toolroom environments.

Key Features

• 180-degree flat-bottom point eliminates the standard drill cone, enabling flat-bottomed holes
• Solid carbide construction provides rigidity and wear resistance in hard and abrasive materials
• Stub/screw machine length body reduces deflection compared to jobber-length bits
• Coolant-through design supports internal coolant delivery for improved tool life and chip flushing
• Tapered web configuration improves strength at the drill core
• Diameter tolerance of +0.0002 to +0.0006 inch (+0.004 to +0.016 mm) meets close-tolerance bore requirements

Compatibility

Designed as an OEM-compatible solid carbide stub drill for use in CNC machining centers, screw machines, and drill presses equipped with collets or chucks accepting a 6.00 mm straight cylindrical shank. Fits the KENNAMETAL Series B707A-FBS product family.

Installation Notes

Installation should be performed by a qualified machinist or toolroom technician familiar with carbide tooling. Ensure the machine spindle and collet or chuck are clean and free of runout before seating the shank. Solid carbide tooling is brittle and should never be used in machines with excessive spindle runout or vibration. Verify coolant-through lines are clear and delivering adequate flow before engaging the cut.