Drill bit GRAPHITE HSS cylindrical 7 mm for metal model 55H027

GRAPHITE HSS cylindrical 7 mm drill bit for metal model 55H027 is a precision cutting tool made from high-speed steel (HSS) and intended for drilling metal surfaces. The 7 mm diameter and cylindrical shank are designed for secure clamping in standard chucks and provide stable rotation for accurate hole making in steel, iron and a range of ferrous and non-ferrous metals. The HSS material offers improved hardness and heat resistance compared with carbon steel, helping retain cutting edge and dimensional accuracy during continuous work.

Advantages

The HSS construction gives the drill bit increased wear resistance and the ability to operate at higher cutting speeds with reduced softening under heat. The cylindrical shank ensures compatibility with drill chucks and straightforward mounting in hand-held drills and drill presses. The 7 mm diameter delivers a balance between rigidity and cutting clearance for clean, round holes while minimizing wandering. The tool is suitable for repeated use in workshop and industrial environments where metal drilling accuracy and tool life are important.

Suitable for

• Drilling through mild and alloy steels
• Creating holes in cast iron and non-ferrous metals such as aluminum and brass
• General metalworking tasks in workshops and maintenance
• Use with hand drills and drill presses for precision holemaking

Key specifications

• Material: High-speed steel (HSS)
• Diameter: 7 mm
• Shank type: Cylindrical shank for standard chucks
• Intended use: Drilling metal (ferrous and non-ferrous)
• Typical applications: Workshop and industrial metal drilling

How to use

Secure the drill bit in the chuck so the shank is fully engaged and tightened. Select an appropriate spindle speed and feed rate for the metal type and thickness—lower speeds for harder steels, higher speeds for softer non-ferrous metals. Use cutting lubricant or coolant when drilling harder materials or for prolonged operations to reduce heat and prolong tool life. Apply steady pressure and allow the tool to cut; avoid excessive force which can cause overheating or breakage. After use, clean chips from flutes and store the bit in a dry place to prevent corrosion.

Usage recommendations

For best results, pre-center holes with a center punch on thin or curved workpieces, use appropriate cutting fluid for the material being drilled, and replace the bit when wear degrades hole quality or increases required cutting force.