Drill America H Cobalt Heavy Duty Drill Bit Pack of 12 - Durable Metal

Our review of the Drill America H Cobalt Heavy Duty Drill Bit pack finds these jobber length bits best suited to metalworkers, fabricators and serious DIYers who regularly drill stainless steel, nickel alloys or other tough materials. The bottom line: these bits are built of heat resistant cobalt steel that lets them run hotter and cut harder metals more reliably than regular high-speed steel, making them a practical choice when durability and sharp, clean holes are a priority.

Key Features

• Cobalt construction: Heat resistant cobalt delivers higher red hardness so the bits can be run at roughly 30 percent greater speeds compared with typical high-speed steel.
• Gold oxide finish: A thin gold oxide surface treatment identifies the bits without changing cut performance, keeping finishes similar to uncoated tools.
• Spiral fluted design: Right-hand spiral flutes evacuate chips up and out of the cut to reduce clogging when drilling deep holes in metal.
• Round shank: Round shanks allow use in a wide variety of chucks and toolholding systems for flexible workshop use.
• Manufacturing standard: Produced to National Aerospace standard 907, indicating consistent dimensions and quality suitable for demanding applications.

Who It's For

These drill bits are aimed at professional tradespeople and dedicated hobbyists who need a reliable stack of jobber length cobalt bits for drilling tough metals like PH stainless steel, inconel and titanium. They suit machine shop tasks and heavy-duty handheld drilling where heat and hardness would blunt ordinary bits quickly.

They are less necessary for casual woodworkers or light-duty home repairs where high-speed steel or coated bits already meet needs. If a user requires specialized coatings for reduced friction in nonmetal applications, or prefers hex shanks for rapid bit changes in cordless drivers, they should consider other options.

Pros & Cons

Pros

• Excellent cutting performance and sustained sharpness when working hardened metals.
• Durable construction lets the bits last noticeably longer than many standard brands.
• Round shank compatibility makes them easy to use in most chucks and drill presses.

Cons

• Gold oxide is mainly an identification finish and does not provide enhanced wear resistance compared with other advanced coatings.
• Angle feedback from some users is mixed, so very fine or specific point geometries may not be ideal for every precision task.

Specifications

Our Verdict

For anyone regularly drilling stainless or other high tensile materials these Drill America cobalt jobber bits deliver durable, sharp performance and good value for money. They are a smart buy for workshops that demand longer life and higher speeds than high-speed steel can provide, though users wanting advanced surface coatings or specialized point angles should evaluate alternatives.

Frequently Asked Questions

Are these bits suitable for stainless steel?
Yes, the cobalt construction and higher red hardness make them well suited to drilling stainless steel and similar tough alloys.

Do the gold oxide finish improve wear resistance?
No, the gold oxide is a thinner identification treatment and performs similarly to uncoated bits in cutting; longevity comes from the cobalt material itself.

Will they fit a standard drill chuck?
Yes, the round shanks are compatible with most drill chucks and drill press holders.