Kennametal 4121491 Screw Machine Drill Bit 14mm Carbide

Product Description

The KENNAMETAL 4121491 is a solid carbide screw machine length drill bit engineered for demanding metal-cutting applications. It features a 14.00 mm (0.5512 inch) diameter, a 140-degree split point for reduced thrust and accurate self-starting, and a TiN tip coating applied at the cutting edge to extend tool life in abrasive materials. Overall length is 107.00 mm (4.2126 inches), keeping the tool compact and rigid in screw machine and CNC lathe setups. The 2-flute right-hand spiral geometry promotes efficient chip evacuation, and the through-coolant design allows direct delivery of cutting fluid to the cutting zone. Licensed machinists and tooling technicians handling precision-tolerance drilling operations are the primary users of this bit.

This drill bit is designed for high-productivity drilling in stainless steel, cast iron, and high-temperature alloys — materials that demand rigid tooling and consistent edge geometry. The screw machine length (stub) configuration provides extra rigidity compared to jobber-length drills, making it well suited for close-tolerance bores on CNC machining centers, turret lathes, and screw machines. The tapered web configuration and 3xD flute-to-diameter ratio support chip control at moderate-to-high feed rates typical of production environments. The straight cylindrical shank seats directly in standard ER collets or drill chucks without adapters.

Key Features

• Solid carbide construction for rigidity and heat resistance in hard and abrasive workpiece materials
• TiN (Tip) coating reduces friction at the cutting edge and improves wear resistance in stainless steel and cast iron
• 140-degree point angle lowers axial thrust and improves centering on flat and curved surfaces
• Through-coolant capability delivers cutting fluid directly to the cutting zone, extending tool life in deep-hole applications
• Screw machine (stub) length body provides maximum rigidity and minimizes deflection in production drilling
• Tapered web and regular spiral flute geometry support reliable chip evacuation at production feed rates
• Complies with DIN 6535 and DIN 6537 standards; specification designation DIN 6537K

Compatibility

The 4121491 belongs to KENNAMETAL Series B051A and covers the 13.50 mm to 17.00 mm drill bit size range. It is compatible with standard straight-shank toolholders, ER collet chucks, and drill chucks accepting a 14.00 mm (0.5512 inch) shank diameter.

Installation Notes

This bit is installed by machinists or tooling technicians on CNC machining centers, turret lathes, or screw machines. Before changing tooling, power down the spindle completely and confirm the machine is in a safe lockout state per shop safety procedures. Seat the straight shank fully and evenly in the collet or chuck, and verify runout before production drilling. Engage through-coolant supply before initiating the cut to prevent premature edge wear.