Guhring 9005520085000 Screw Machine Drill Bit 8.50mm

Product Description

The GUHRING 9005520085000 is a stub-length screw machine drill bit designed for high-performance drilling in production and machining environments. Built from high speed steel with a bright, uncoated finish, it features a parabolic flute geometry and a web-thinned, parallel web configuration that improves chip evacuation and reduces thrust at the cutting edge. The 130-degree split point starts on contact without walking, making it well suited for aluminum and similar non-ferrous workpieces. At 8.50 mm (0.3346 inches) in diameter, this bit conforms to DIN 1897 standards and is intended for use by machinists and tool-and-die professionals running screw machine or CNC drilling operations.

This drill bit is built for stub-length applications where rigidity and minimal deflection are priorities. The shorter overall length of 3.1102 inches keeps the bit stiff in the cut, reducing vibration and improving hole quality. With a maximum drilling depth of 0.9550 inches and a 3xD flute-to-diameter ratio, it is optimized for shallow to mid-depth holes in aluminum workpieces, though it also performs in other soft to medium-hardness materials. It is a single-piece, individual unit packaged for direct shop or bench use.

Key Features

• 8.50 mm (0.3346 inches) diameter per DIN 1897 specification, tolerance +0.000 to -0.022 mm
• Parabolic flute design promotes aggressive chip clearing in deep and through-hole drilling
• Web-thinned parallel web reduces cutting resistance and entry thrust
• 130-degree standard point angle for self-centering starts on most metals and non-ferrous materials
• Straight-cylindrical shank fits standard drill chucks and collet holders without modification
• Stub (screw machine) length improves rigidity compared to jobber-length equivalents
• Right-hand cut, two-flute configuration for conventional CNC and manual drilling setups

Compatibility

Designed as a DIN 1897 Series 552 stub-length drill bit compatible with standard straight-shank drill chucks and collet systems used in screw machine, CNC, and general machining applications. Primary workpiece material is aluminum; suitable for other soft to medium-hardness materials where parabolic flute geometry is appropriate.

Installation Notes

Installation and use should be performed by qualified machinists familiar with cutting tool selection and machine setup. Ensure the drill chuck or collet is properly sized and torqued to the straight-cylindrical shank before operation. Confirm spindle speed and feed rate are appropriate for the workpiece material and bit diameter before drilling. Do not exceed the maximum drilling depth of 0.9550 inches without retracting to clear chips, as parabolic flutes are optimized for periodic chip evacuation in stub-depth applications.