Twist drill bit (HSS Cobalt) Bosch 1.2 cm diameter, 1 pc

Bosch HSS Cobalt twist drill bit, 1.2 cm diameter, single piece. This high-speed steel (HSS) drill bit with added cobalt is engineered for drilling hard and heat-resistant materials, including stainless steel and alloyed steels. Manufactured to DIN 338 with Type N flute geometry and a 135° split-point tip, the bit provides accurate centring and reduced walking. The cylindrical shank matches the drill diameter for secure clamping in handheld drills and drill stands, making it suitable for precision metalworking, repairs and tasks that require reliable heat resistance and longer tool life.

Advantages

The cobalt alloy increases heat resistance and wear performance compared with standard HSS, extending service life when drilling at higher speeds or in demanding materials. The 135° split-point tip and DIN 338 geometry improve centring and reduce the need for pilot holes, delivering clean, accurate holes. The diameter-tolerant h8 manufacturing ensures consistent hole sizes, while the cylindrical shank enables stable mounting in both handheld and stationary drilling equipment.

Suitable for

• Drilling stainless steel and acid- or heat-resistant steels
• Alloyed and non-alloyed steels
• Cast iron and cast steel workpieces
• Precision metalworking, maintenance and repair jobs

Key specifications

• Material: High-speed steel with cobalt alloy
• Diameter: 1.2 cm
• Tip angle: 135° split-point
• Flute type: Type N (standard flute geometry)
• Manufacturing standard: DIN 338
• Diameter tolerance: h8
• Shank: Cylindrical, shank diameter equals drill diameter
• Intended use: Handheld drills and drill stands

How to use

Secure the drill bit in the chuck so the shank is fully clamped. Select an appropriate drilling speed and apply steady feed pressure; lower speeds and cutting fluid are recommended for stainless steel and heat-resistant alloys to reduce friction and extend bit life. Use the split-point tip to position the bit precisely and start drilling with light pressure until the tip has established a groove, then continue with consistent pressure. Retract the bit periodically to clear chips when drilling deep holes.

Usage recommendations

Use cutting fluid or suitable lubricant when drilling stainless steel and other hard alloys, and avoid excessive speed or force to prevent overheating. For the most accurate holes, clamp the workpiece securely and, when necessary, use a center punch or pilot drill for initial positioning on smooth surfaces.