Irwin 1/4" x 3-5/16" Left Cobalt HSS Fractional Drill Bit (30516)

The Irwin 1/4" x 3-5/16" Left Cobalt HSS Fractional Drill Bit (30516) is a specialized tool engineered for precision and reliability when working with tough metals and broken fasteners. Part of the Series 305, this mechanics length drill bit is crafted from M-42 high-speed steel with an 8% cobalt alloy. This premium material composition provides exceptional heat and abrasion resistance, making it an effective choice for drilling into challenging materials like hardened steel and stainless steel.

KEY FEATURES AND BENEFITS:

• Left-Hand Cutting Direction: The counter-clockwise spiral is specifically designed to loosen broken screws and bolts as you drill, often extracting them without needing a separate screw extractor. This saves time and simplifies the removal process.
• 8% Cobalt Alloy: The M-42 high-speed steel with 8% cobalt offers superior heat and abrasion resistance, allowing the drill bit to maintain its sharpness and effectiveness when drilling through hardened steel, cast iron, and other high-tensile strength materials.
• Mechanics Length Design: The shorter overall length of the bit provides increased rigidity and strength. This reduces the risk of the bit breaking under high torque and pressure, making it more reliable for heavy-duty applications.
• 135˚ Split Point: The split point design allows the bit to self-center on contact, eliminating the need for a pilot hole in most cases and preventing the bit from "walking" or slipping on the workpiece. It also reduces the required drilling pressure for a smoother start.
• Gold Oxide Finish: This coating helps to reduce friction and provides additional protection against corrosion, extending the bit's lifespan and performance.

SPECIFICATIONS:

• Drill Bit Type: Left-Hand Mechanics Length Cobalt HSS Fractional Drill Bit
• Series: 305
• Drill Diameter: 1/4"
• Overall Length: 3-5/16"
• Flute Length: 1-3/4"
• Point Angle: 135˚
• Shank Diameter: 1/4"
• Material: M-42 High-Speed Steel with 8% Cobalt
• Finish: Gold Oxide
• Cutting Direction: Left-Hand (Counter-clockwise)

HOW TO USE:

1. Prepare the Work Area: Ensure the workpiece is securely clamped and that you have a clear, safe area to work.
2. Select the Correct Drill: Choose the appropriate size drill bit for the broken fastener. The goal is to drill a pilot hole into the center of the broken bolt or screw.
3. Attach to Drill: Securely insert the Irwin 1/4" Left Cobalt HSS Drill Bit into your drill's chuck. Crucially, set your drill to a reverse (counter-clockwise) setting.
4. Position and Begin Drilling: Place the bit's tip directly onto the center of the broken fastener. Apply steady, firm pressure and begin drilling at a low to medium speed.
5. Drill and Observe: As the drill bit cuts into the fastener, the left-hand spiral may catch and begin to back out the broken piece. Continue drilling until the fastener is either removed or a sufficient pilot hole is created for an extractor, if necessary.

BENEFITS OF USING IRWIN 1/4" X 3-5/16" LEFT COBALT HSS FRACTIONAL DRILL BIT (30516):

• Effectively removes broken fasteners, saving time and effort.
• Reduces the need for separate screw extractors in many situations.
• Provides greater strength and stability due to its shorter, mechanics length design.
• Maintains a sharp cutting edge under high heat, allowing for longer tool life.
• Reduces the likelihood of drill bit "walking" at the start of a cut.

FEATURES:

• M-42 cobalt-infused steel for durability
• Precision 135° split point aids fast, centered starts
• Reinforced web design enhances strength
• Corrosion-resistant gold oxide coating
• Optimized cutting lips reduce required torque
• Robust spiral flute improves chip removal