Guhring 9002050004600 Jobber Drill No. 77 Hss

Product Description

The GUHRING 9002050004600 is a No. 77 wire-gauge jobber-length drill bit ground from M2 high speed steel with a bright, uncoated finish. It carries a standard 118-degree split point and a web-thinned, tapered web to reduce thrust and improve chip evacuation. The two-flute spiral configuration follows DIN 338 geometry, yielding a right-hand cutting action suited for precision small-diameter drilling. With an overall length of 20.00 mm and a flute length of 5.00 mm, this bit is sized for tight-tolerance work in cast iron and steel. Machinists, tool-and-die technicians, and maintenance professionals reach for this size when drilling pilot holes, clearance holes, or small fastener holes in ferrous materials.

This jobber drill is designed for general-purpose drilling operations in cast iron and steel workpieces. Its 0.46 mm straight-cylindrical shank fits standard precision chucks and collets. The DIN 338 Series 205 specification makes it a common choice for manual drill presses, CNC machining centers, and hand-held power tools where consistent small-diameter hole quality is required. The 5xD flute-to-diameter ratio provides adequate chip clearance at this micro-diameter range.

Key Features

• No. 77 wire gauge, 0.0181 inch decimal equivalent diameter
• 118-degree standard point angle with web-thinned, tapered web for reduced thrust
• M2 high speed steel construction for durability in ferrous materials
• Bright, uncoated finish compatible with cutting fluids and dry drilling
• Right-hand spiral flute following DIN 338 Series 205 geometry
• Straight-cylindrical shank for broad chuck compatibility

Compatibility

Designed as a general-purpose DIN 338 jobber drill for use in cast iron and steel. Primary workpiece material codes K and P. No coolant-through feature; suitable for external flood coolant or dry cutting only.

Installation Notes

Installation and use should be performed by qualified machinists or maintenance technicians familiar with small-diameter drill bit handling. Secure the straight-cylindrical shank firmly in a precision keyless or keyed chuck before operation to prevent runout. At this micro-diameter range, feed rates must be carefully controlled to avoid bit deflection or breakage. Replace worn or chipped bits before use, as regrinding sub-0.5 mm shanks requires specialized equipment.