Drill bit GRAPHITE 3 mm Cobalt for metal and hard materials, model 57H020

GRAPHITE 3 mm cobalt drill bit model 57H020 is designed for drilling metal and other hard materials. Manufactured from a cobalt alloy, this 3 mm drill bit offers improved heat resistance and greater wear durability compared with standard high-speed steel bits. It is suitable for use in handheld drills as well as drill presses and is intended for producing precise small-diameter holes in steel, stainless steel and similar hard materials in workshop and maintenance environments.

Advantages

The cobalt composition increases red-hardness and maintains cutting performance at higher temperatures, reducing the likelihood of rapid wear when drilling tough metals. The 3 mm diameter ensures accuracy for small holes and fine work. Ground cutting edges and a rigid shank provide stable drilling with minimized wobble. The bit’s construction supports repeated use in demanding conditions and helps deliver consistent hole quality in hard materials.

Suitable for

• Drilling small-diameter holes in carbon steel and alloy steel
• Working with stainless steel and other corrosion-resistant metals
• Workshop repair, maintenance and fabrication tasks
• Precision tasks requiring accurate 3 mm holes

Key specifications

• Diameter: 3 mm
• Material: cobalt alloy cutting composition
• Intended materials: steel, stainless steel and other hard metals
• Suitable tool types: handheld drill and drill press
• Shank: straight round shank for standard chucks

How to use

Secure the drill bit in the chuck, ensuring it is centered and tightened. Mark and clamp the workpiece to prevent movement. Use a suitable cutting speed and apply steady pressure; when drilling stainless or harder steels, adopt a slower speed to reduce heat build-up. Use cutting fluid or lubricant to improve heat dissipation and extend tool life. Withdraw the bit periodically to clear chips and prevent clogging; finish the hole by reducing feed as the bit breaks through.

Usage recommendations

For best results when drilling hard metals, run the drill at lower speeds, keep cutting fluid at the point of contact, and avoid excessive axial force that can cause bit breakage. Inspect the bit for wear and replace when cutting quality deteriorates.