Twist Drill Bit Set Irwin 10502527 — 5 mm diameter, 10 pcs

Irwin 10502527 is a set of ten 5 mm twist drill bits manufactured for general and heavy-duty drilling tasks. Each bit is made from high-speed steel with 5% cobalt alloy for improved heat and abrasion resistance, and finished to DIN 338 dimensional standards. The 135° split point geometry reduces bit walk and starts cutting immediately, while the heavy-duty web construction increases strength and helps resist breakage during demanding jobs in metal, wood and plastic.

Advantages

These HSS cobalt drill bits combine enhanced wear resistance from the cobalt content with a sturdy core that increases torque tolerance and durability. The 135° split point minimizes the need for center punching and improves accuracy when beginning a hole. Conformance to DIN 338 ensures consistent dimensions for use in standard chucks and holders. The uniform 5 mm diameter across all ten pieces makes the set convenient for repetitive work where the same hole size is required.

Suitable for

• Drilling holes in a variety of metals, including hardened and heat-treated alloys
• General-purpose wood drilling and joinery tasks
• Plastic and composite material drilling where clean 5 mm holes are needed
• Workshop assembly, repair, and maintenance jobs requiring consistent hole size

Key specifications

• Type: twist drill bit set, high-speed steel with cobalt alloy
• Diameter: 5 mm (all pieces identical)
• Quantity: 10 pieces per pack
• Point angle: 135° split point for reduced walking and rapid penetration
• Construction: heavy-duty web for increased strength
• Standards: manufactured to DIN 338 dimensional and tolerance specifications
• Recommended materials: metal (including hardened alloys), wood, plastic

How to use

Secure the drill bit firmly in the drill chuck and set the drill to an appropriate speed for the material being drilled — lower speeds for hardened metals and higher speeds for wood and plastics. Use cutting lubricant when drilling metal to reduce heat build-up and extend bit life. Start drilling with light pressure to allow the 135° split point to locate the hole, then apply steady pressure and coolant or intermittent pecking when cutting hard or deep holes. After use, clean chips and lubricant from the flutes and store the bits in their case to prevent damage.

Usage recommendations

For best performance on hardened or abrasive alloys, use a suitable cutting fluid, maintain low to moderate speeds, and avoid excessive axial pressure. When drilling thin or fragile materials, consider backing the workpiece to prevent exit burrs. Replace bits showing significant wear, chipping, or loss of point geometry to maintain hole quality and operator safety.