Osg HP253-4055 Screw Machine Drill Bit 10.3mm Carbide

Product Description

The OSG HP253-4055 is a solid carbide screw machine length drill bit engineered for high-performance drilling in demanding metal-cutting applications. With a 10.3 mm (0.4055 inch) diameter and a 140-degree point angle, this bit delivers precise entry and reduced thrust in hard materials. The R-thinned point geometry minimizes walking at the start of the cut. Coolant-through capability supports continuous operation in production environments where heat management is critical. The two-flute spiral design with a tapered web configuration promotes efficient chip evacuation. This bit is sized for machinists, tool-and-die shops, and maintenance professionals working with ferrous metals.

The HP253-4055 is designed for drilling steel, alloy steel, and cast iron. Its screw machine length body, with a 55 mm flute length and 102 mm overall length, fits standard drill chucks and CNC machining centers without extended tool-change adjustments. The straight-cylindrical shank at 12 mm diameter provides positive grip in collets and chucks. The 3xD flute-to-diameter ratio makes this bit particularly well suited to short-hole drilling cycles common in production machining and fabrication work.

Key Features

• Solid carbide construction for rigidity and wear resistance in ferrous metal drilling
• 140-degree point angle reduces thrust and improves entry accuracy
• R-thinned point minimizes drill walk and lowers cutting force at entry
• Coolant-through design supports high-cycle production drilling and heat control
• Straight-cylindrical 12 mm shank fits standard collets and drill chucks
• Diameter tolerance of plus 0.007 to plus 0.025 mm for consistent hole sizing

Compatibility

Designed for use in drilling steel, alloy steel, and cast iron workpieces. Fits machining centers, CNC lathes, and drill presses equipped with collets or chucks accepting a 12 mm straight-cylindrical shank. Suitable for applications within the 9.50 mm to 11.00 mm drill bit size range class per the HP253 series specification.

Installation Notes

Installation is performed by qualified machinists or CNC operators. Secure the shank fully in the collet or chuck before operation and verify runout before beginning a drilling cycle. Power down and lock out the machine spindle before changing or inspecting the bit. Coolant supply lines should be confirmed open and flowing when coolant-through operation is used to prevent thermal damage to the cutting edge.