Cobalt Heavy Duty #6 Drill Bit Pack of 12 - Durable Jobber Length

In this review the Drill America #6 Cobalt Heavy Duty Drill Bit pack is evaluated for tradespeople and serious hobbyists who regularly drill tough metals. The bottom line: this 12-pack is worth considering if you need dependable, long-lasting bits that handle stainless steel, nickel alloys and other high tensile materials better than ordinary high-speed steel. The review focuses on real-world cutting performance, material and coating details, and whether these bits represent good value for metalworking tasks.

Key Features

• Cobalt steel construction: Provides higher red hardness so the bits retain cutting edge at higher speeds and resist wear when drilling hard metals like stainless and inconel.
• Gold oxide surface treatment: A thin oxide layer reduces light corrosion and helps identify the product without significantly changing cutting performance compared with uncoated bits.
• Right-hand spiral flutes: Evacuate chips up and out of the hole when run clockwise, reducing clogging and helping maintain a cleaner cut in deep holes.
• Round shank design: Fits a wide range of drill chucks and toolholding systems for easy, versatile use across hand drills and drill presses.
• Manufactured to NAS 907: Built to a recognized aerospace-related standard, indicating consistent tolerances and quality for demanding applications.

Who It's For

These bits are aimed at metalworkers, fabricators and serious DIYers who need a tool that stands up to frequent drilling in tough alloys. If your work regularly includes PH stainless steel, titanium or nickel alloys, the increased heat resistance and edge life of cobalt steel is a practical advantage.

Someone who only drills wood, soft metals or occasional light tasks may find this pack overkill and could save money with standard high-speed steel bits. Also, if a hex or reduced-shank mounting is required for your quick-change holder, the round shank format may be less convenient.

Pros & Cons

Pros

• Excellent durability and longer life than typical HSS bits when cutting high tensile metals.
• Sharp, clean cuts and reliable drill performance as noted by multiple users.
• Good value for money in a 12-piece pack for frequent metalworking use.

Cons

• Gold oxide coating is thin and does not provide the lubricity or wear resistance of specialized coatings; performance is similar to uncoated cobalt.
• Round shanks may require different holders for certain quick-change or reduced-shank chucks.

Specifications

Our Verdict

The Drill America #6 Cobalt Heavy Duty 12-pack is a sensible buy for anyone who frequently drills high tensile or heat-resistant metals and needs bits that stay sharp longer. With cobalt construction, jobber length versatility and a value-oriented pack size, it delivers strong performance and durability for metalworking tasks, though the thin gold oxide finish offers limited additional protection.

Frequently Asked Questions

Are these bits suitable for stainless steel?
Yes. The cobalt steel and higher red hardness make them effective for drilling stainless steel and other hard alloys.

Will the gold oxide coating extend tool life significantly?
The gold oxide is a thin surface treatment that mainly reduces light corrosion and identifies the bits; it does not dramatically change cutting life versus uncoated cobalt.

Do they fit standard drill chucks?
Yes. The round shank design fits most standard chucks and drill presses, though reduced-shank holders may require an adapter.