Step drill bit Irwin 10502853 — step bit, drill diameter 2.2 cm

The Irwin 10502853 step drill bit is engineered to drill progressively larger round holes with a single cutting tool. With a maximum step diameter of 2.2 cm, this step bit is intended for use with standard power drills to create and enlarge openings in thin materials such as sheet metal. Constructed from industrial-grade M7 high speed steel and featuring a self-centring point and a flatted shank, it delivers controlled drilling performance and reduces the need for centre punching or frequent tool changes.

Advantages

The single-flute design provides improved control when drilling into sheet metal and helps produce clean, circular holes. The flute geometry is optimized to evacuate chips and reduce burring, while the self-centring point prevents walking at the start of a cut for accurate hole placement. The M7 high speed steel construction offers hardness and wear resistance suitable for repeated use in thin metallic materials, and the flatted shank minimises slippage in the drill chuck.

Suitable for

• Drilling and enlarging holes in sheet metal
• Electrical and HVAC installations where multiple hole sizes are required
• Metalworking tasks on thin steel, aluminium or similar gauge materials
• Situations that require quick step-size changes without swapping tools

Key specifications

• Tool type: Step drill bit
• Maximum drill diameter: 22 mm
• Material suitability: Sheet metal and thin-gauge metals
• Cutting material: M7 high speed steel
• Flute design: Single flute for chip evacuation and control
• Tip type: Self-centring point to prevent walking
• Shank style: Flatted cylindrical shank to reduce chuck slip

How to use

Mark the hole centre and clamp the workpiece securely to prevent movement. Fit the step drill bit into the drill chuck and tighten the flatted shank to reduce slippage. Start drilling at low speed to allow the self-centring point to locate the hole, then increase speed as appropriate for the material thickness. Apply steady, moderate pressure and withdraw occasionally to clear chips. For larger final diameters, progress through the steps without changing tools, stopping briefly between steps to ensure a clean cut.

Usage recommendations

Use cutting fluid or light oil when drilling stainless or thicker sheet metals to extend tool life and improve chip evacuation. For the best results, secure thin panels with clamps and support the area around the hole to reduce vibration and deformation.