HSS Twist Drill Bits Cobalt Bosch 2608585888 5 Piece Set

HSS Twist Drill Bits Cobalt Bosch 2608585888 5 Piece Set — precision-ground cobalt HSS twist drills for metalworking. With 5% cobalt alloy and fully ground high-speed steel, these bits deliver extended lifetime, improved wear resistance and heat protection for drilling stainless and alloyed steels. The set contains five sizes suitable for a range of workshop and on-site drilling tasks; each bit conforms to DIN 338, Type N with a 135° split point tip and h8 diameter tolerance. The cylindrical shank matches the drill diameter and is intended for use in drill presses and handheld drill drivers.

Advantages

The cobalt alloy (5%) combined with fully ground HSS construction provides enhanced hardness at elevated temperatures, resulting in longer tool life when drilling stainless steel and other difficult-to-machine metals. Two cutters and two flutes improve chip evacuation and maintain cutting performance. The 135° split-point tip ensures accurate centring and reduces walking at drill start, while the h8 tolerance and DIN 338 manufacturing standard ensure consistent dimensions and fit.

Suitable for

• Alloyed and non-alloyed steels
• Stainless steel
• Cast iron and cast steel
• Acid- and heat-resistant steels
• Workshop drilling in drill presses and handheld drill drivers

Key specifications

• Brand: Bosch
• MPN: 2608585888
• EAN: 3165140521239
• Material: HSS with 5% cobalt
• Standard: DIN 338
• Type: N (flute angle)
• Tip: 135° split-point
• Shank: cylindrical (shank = drill diameter)
• Tolerance: h8
• Set: 5 pieces

How to use

Secure the appropriate drill bit in the drill chuck or drill press so the cylindrical shank seats fully and concentric. Choose suitable cutting speed and feed for the material—use lower speeds for stainless and heat-resistant steels. Apply firm, steady pressure and allow chips to evacuate through the flutes; pause periodically to clear chips and prevent overheating. Use cutting fluid for improved cooling and lubrication when drilling stainless or alloyed steels.

Usage recommendations

For best results when drilling stainless steel and other hard alloys, use a cutting lubricant, moderate feed rates and lower spindle speeds; avoid excessive pressure that can cause premature wear. Replace bits showing significant wear or chipping to maintain hole accuracy.