Twist drill bit Irwin 10502562 — 8.5 mm diameter, single piece

Irwin 10502562 is a single-piece twist drill bit with an 8.5 mm diameter designed for general and demanding drilling tasks. Made from high-speed steel with 5% cobalt, this 8.5 mm drill bit offers increased heat and abrasion resistance compared with standard HSS bits. The 135° split point reduces bit walking and starts cutting immediately, while the reinforced web and cylindrical shank provide strength and stable mounting in electric or cordless drills. With an overall length of 117 mm, the bit is suitable for creating clean, precise 8.5 mm bores in a range of workshop and on-site applications.

Advantages

The Irwin 8.5 mm twist drill bit combines cobalt-enriched HSS material and a heavy-duty web construction to deliver enhanced durability and resistance to heat and wear. The 135° split point improves centering and reduces the need for pilot holes, minimizing slippage on smooth surfaces. Manufactured to DIN 338 standards, the bit provides consistent geometry and reliable performance when drilling alloyed steels, stainless steel and other metals, as well as wood and plastics for general tasks.

Suitable for

• Drilling 8.5 mm holes in alloyed steel and stainless steel
• Workshop repair and assembly of metal components
• On-site construction tasks requiring 8.5 mm bores
• Drilling in wood and plastics for fittings and installations

Key specifications

• Type: single-piece twist drill bit
• Diameter: 8.5 mm
• Overall length: 117 mm
• Material: high-speed steel with 5% cobalt
• Point angle and geometry: 135° split point
• Shank type: cylindrical
• Quantity: 1 piece

How to use

Secure the Irwin 8.5 mm twist drill bit in a compatible drill chuck, ensuring the cylindrical shank is clamped firmly. Select an appropriate drill speed for the material: lower speeds for stainless and hardened steels, medium to higher speeds for softer metals, wood and plastics. Use cutting fluid or lubricant when drilling metals to extend bit life and reduce heat, and apply steady, moderate feed pressure. Clear chips periodically to avoid clogging and overheating. For precise starts on smooth or hardened surfaces, consider using a center punch or pilot hole before drilling.

Usage recommendations

Use cutting fluid and controlled speeds when drilling stainless or alloyed steels; allow the bit to cool between prolonged cuts to preserve the cobalt-enhanced HSS edge. For non-metal materials, moderate speeds and firm clamping will produce clean holes without excessive heat buildup.