DeWalt DT4922 Cobalt Jobber Drill Bit 3.3mm, 10-piece set

The DeWalt DT4922 Cobalt Jobber Drill Bit set consists of 10 high-performance drill bits, each with a 3.3mm diameter. These bits are engineered for demanding drilling tasks in hard metals, specifically stainless steel. Their robust construction incorporates cobalt, which provides superior heat resistance and structural integrity, ensuring that the bits maintain their sharpness and performance even under high-friction conditions during intensive metalworking operations.

Advantages

The primary advantage of these cobalt drill bits is their exceptional durability when working with abrasive and hard materials. The inclusion of cobalt in the alloy significantly increases the melting point of the steel, allowing for efficient drilling without the risk of premature dulling or deformation. These bits are designed to provide consistent, clean, and precise holes, reducing the need for secondary finishing work. Their jobber length provides a balance between stability and reach, making them a reliable choice for both handheld power drills and stationary drill presses.

Suitable for

• Drilling into stainless steel and high-tensile alloys
• Professional metal fabrication and industrial maintenance
• Precision hole drilling in cast iron and hardened steel
• General metalworking tasks requiring high heat resistance

This set may not be suitable for drilling into soft materials like wood or plastic, as the aggressive cutting geometry and cobalt composition are optimized for metal. Furthermore, these bits are not intended for masonry or concrete applications, where specialized carbide-tipped bits are required to prevent damage to the cutting edge.

Key specifications

• Diameter: 3.3mm
• Material: Cobalt alloy
• Quantity: 10 pieces
• Application: Hard metals and stainless steel
• Design: Jobber length

To use these drill bits, ensure the workpiece is securely clamped to prevent movement during the drilling process. Insert the bit into the chuck of your drill, ensuring it is tightened properly. It is recommended to use a low drilling speed when working with stainless steel to prevent overheating and to apply a suitable cutting fluid or lubricant to extend the life of the bit and improve the quality of the hole.

What to consider before purchase

• Verify the required hole diameter for your specific project
• Ensure your drill chuck is compatible with 3.3mm cylindrical shanks
• Consider the hardness of the material you intend to drill

For optimal performance and longevity, always maintain a steady, moderate pressure and use a high-quality cutting oil. Avoid excessive speed, as heat buildup is the primary cause of premature wear in cobalt drill bits.