Best Drill Bits for Hardened Steel

By: Contributors  | 
Drilling into hardened steel.
Making light work of tough steel — carbide and cobalt drill bits are the champions of drilling through hardened steel.
Science Channel

Drilling through metal is a lot harder than drilling through wood. It requires a tougher drill bit and hardened steel requires special attention and tools. To help, here are some tips on the best drill bits for hardened steel. From DIY enthusiasts to professional craftsmen, everyone needs the right drill bits to make the job easier, faster, and more efficient.


Understanding Hardened Steel and Its Challenges

Drilling hardened steel is a task that demands not only skill but also the right tools. Hardened steel, known for its high durability and resistance to wear and tear, poses a unique challenge.

Unlike softer materials, it requires specific drill bits that can penetrate without losing their edge or causing damage to the material or the tool.


The Might of Carbide Drill Bits

When it comes to drilling hardened steel, carbide drill bits are the champions. The carbide drill bit has exceptional hardness and resistance to high temperatures make them ideal for this task.

Not only do they maintain their sharpness longer than their counterparts, but they also offer precision that is unmatched, making them a top choice for professionals [source: Tool Shop Parweld].


Cobalt Drill Bits: A Robust Alternative

Another excellent choice for drilling hardened steel or to drill holes in general is cobalt drill bits. These bits, made with a significant percentage of cobalt, are incredibly resilient and effective at maintaining their sharpness.

Unlike high speed steel bits, they are particularly useful when drilling through hardened metal, offering durability and efficiency [source:].


The Importance of a Drill Press for Precision

Drill presses can significantly enhance your drilling accuracy, especially when working with hardened steel. The stability and precision of this drill are crucial for ensuring that your drill bits do not wander or break, resulting in cleaner and more accurate holes.


The Role of Speed and Pressure in Drilling Hardened Steel

When drilling hardened steel, the right combination of speed and pressure is vital. Using a slow speed and applying steady pressure allows the drill bit to cut through the steel effectively without overheating or wearing out quickly [source: Chicago Pneumatic].


Keeping Your Drill Bits Cool

Heat is a major enemy when drilling hardened steel. It's important to keep your drill bits cool to prevent them from losing their temper and becoming dull. Using a cooling agent or lubricant, like cutting oil, can significantly increase the lifespan of your drill bits [source: Thyssenkrupp].


Sharpening Your Drill Bits Regularly

Regular maintenance, including sharpening your drill bits, is essential for effective drilling. A well-sharpened drill bit can make a significant difference in how easily and cleanly it cuts through hardened steel.


Choosing the Right Angle for Drilling Hardened Steel

The angle of the drill bit is crucial when drilling through hardened steel. A bit with a 135-degree angle is often recommended as it offers a good balance between sharpness and strength, making it ideal for penetrating tough materials [source: Regal Cutting Tools].


The Versatility of Carbide Tipped Drills

Carbide tipped drills are an excellent investment for those who frequently drill hardened steel. These drills have a carbide tip attached to a softer steel body, offering a combination of toughness and flexibility that is ideal for handling hardened steel's demands [source: Tool Shop Parweld].


Safety First: Protecting Yourself and Your Equipment

When drilling hardened steel, safety should always be a priority. Wearing protective gear and ensuring your equipment is in good condition can prevent accidents and ensure a smooth drilling experience.

Drilling hardened steel doesn't have to be a daunting task. With the right tools and techniques, you can easily tackle this challenging material. Remember, choosing the right drill bits, such as carbide or cobalt ones, using a drill press for stability, and maintaining your tools will make a significant difference. Stay safe, and happy drilling!

Steel Drill Bits FAQ

Which is harder cobalt or titanium drill bits?
Titanium-coated bits are better for drilling into softer surfaces like wood or soft metals, whereas cobalt bits have no problem tackling materials such as cast iron or titanium. Cobalt bits are more expensive than titanium ones.
What is a cobalt drill bit?
Cobalt drill bits are a mixture of steel and a smaller percentage of cobalt, commonly between 5 and 8 percent or so.
Can titanium drill bits be used on metal?
You can use titanium drill bits to drill metal. However, cobalt drill bits may pose a better, if more expensive, option.
What is the best drill bit for hardened steel?
Cobalt poses the best option for drilling through hardened steel.