Drilling through steel can be a challenging task, but with the right drill bits, it becomes significantly easier and more efficient. Standard drill bits often struggle against the hardness and abrasive nature of steel, leading to rapid dulling, overheating, and inefficient hole drilling. Whether you’re a professional welder, a metalworker, or a DIY enthusiast tackling a home project, investing in high-quality drill bits designed specifically for steel is crucial for achieving clean, precise holes and prolonging the life of your tools. This comprehensive guide will explore the best drill bits for steel on the market, detailing their features, benefits, and why they stand out from the competition.
Quick Product Comparison
Our Top 5 Best Drill Bits For Steel Reviews – Expert Tested & Recommended
1. DEWALT 21-Piece Titanium Nitride Coated Pilot Point Drill Bit Set for Steel
The DEWALT 21-Piece Titanium Nitride Coated Pilot Point Drill Bit Set offers exceptional quality and performance for drilling in various metals, including steel. Featuring a durable titanium nitride coating and a pilot point tip, these bits are designed to deliver longer life and cleaner holes. It’s a versatile set that provides outstanding durability and reliability for everyday use.
Key Features That Stand Out
- ✓ Titanium Nitride (TiN) coating for enhanced durability, reduced friction, and prolonged bit life.
- ✓ Pilot Point tip design ensures accurate starts, preventing bit walking and creating clean, burr-free holes.
- ✓ Comprehensive 21-piece set covers a wide range of common drilling sizes for versatility.
- ✓ Engineered for general-purpose drilling in mild to medium-hard steel and other metals.
- ✓ Constructed with high-quality materials for outstanding reliability in daily use.
Why We Recommend It
This DeWalt set strikes an excellent balance between performance, durability, and value, making it our top choice for general steel drilling tasks. The TiN coating and pilot point tip significantly improve drilling efficiency and bit longevity, ensuring consistent results. It’s a reliable workhorse for both professionals and serious DIYers.
Best For
Ideal for everyday drilling in mild to medium-hard steel, general metal fabrication, automotive repair, and home workshop projects where a comprehensive and durable set is required.
Pros and Cons
Pros:
- Titanium Nitride coating enhances durability and cutting speed.
- Pilot Point tip ensures accurate, clean holes without walking.
- Comprehensive 21-piece set for various applications.
- Reliable and trusted DeWalt brand quality.
- Good value for a coated, professional-grade set.
Cons:
- May not be optimal for extremely hardened or thick stainless steel without proper coolant.
- TiN coating can eventually wear off with extensive heavy use.
Customer Reviews
Customer Review: This is an excellent drill bit set from DeWalt. I’d been eyeing it for a long time, waiting for the price to drop, and it was definitely worth the wait. Once it went on sale, I picked it up, and I’m glad I finally did—great quality and performance.
Customer Review: This is an excellent drill bit set from DeWalt. I’d been eyeing it for a long time, waiting for the price to drop, and it was definitely worth the wait. Once it went on sale, I picked it up, and I’m glad I finally did—great quality and performance.
2. BOSCH CO14B 14-Piece Cobalt M42 Drill Bits with Three-Flat Shank for Stainless Steel
The BOSCH CO14B 14-Piece Cobalt M42 Drill Bits set is engineered for superior performance in challenging materials like stainless steel. These jobber-length bits contain 8% M42 Cobalt alloy, providing upgraded durability and exceptional heat resistance. Designed with a three-flat shank, they ensure a secure grip and prevent slippage in the drill chuck, offering outstanding durability and reliability even in high-temperature applications.
Key Features That Stand Out
- ✓ M42 Cobalt alloy (8% Cobalt) construction provides extreme hardness and superior heat resistance.
- ✓ Specifically designed for drilling through tough metals, including stainless steel and hardened alloys.
- ✓ Three-flat shank prevents bit slippage in the drill chuck, ensuring consistent torque transfer.
- ✓ Jobber-length bits offer a balance of reach and strength for various drilling applications.
- ✓ Delivers up to 10 times longer life compared to standard high-speed steel (HSS) bits.
Why We Recommend It
This Bosch Cobalt M42 set is a powerhouse for tackling the most demanding drilling tasks, especially in stainless steel. Its enhanced alloy material withstands high temperatures, maintaining sharpness and efficiency over extended periods. It’s a robust choice for anyone needing reliable performance in tough metals.
Best For
Professionals and serious DIYers who frequently work with stainless steel, cast iron, high-strength alloys, and other hard-to-drill metals where heat and durability are critical factors.
Pros and Cons
Pros:
- M42 Cobalt content provides exceptional hardness and heat resistance.
- Superior performance and extended lifespan in tough metals.
- Three-flat shank ensures a secure, slip-free grip in the chuck.
- Trusted Bosch brand known for quality and innovation.
- Ideal for rigorous use in stainless steel applications.
Cons:
- Higher price point compared to standard HSS or TiN-coated bits.
- Smaller set (14 pieces) might not cover all possible size requirements.
Customer Reviews
Customer Review: Anything bosch makes is good, but i feel like they have it down pat when it comes to stuff like twist drills and bits. The M42 cobalt keeps the drill from getting too hot and also acts as a “lubricant”, both contributing to keeping a sharp cutting edge, giving it quality and ease of use. These factors are important.
Customer Review: This is a great drill bit set. The reason I purchased this set is because I needed to drill and tap a hole in the end of a lawnmower engine crankshaft. Rather than buying just that drill bit I decided to get a whole set, because I knew I would need drill bits again. I decided to go with this set over others due to the positive reviews.
3. BOSCH Cobalt M42 21-Piece Drill Bit Set with Three-Flat Shank for Stainless Steel and Tough Metals
The BOSCH Cobalt M42 21-Piece Drill Bit Set provides the advanced performance of M42 Cobalt in a comprehensive set, making it an excellent budget-friendly choice for tough metals. These bits are engineered for high heat resistance and durability, containing 8% Cobalt alloy to deliver significantly extended life compared to standard bits. The three-flat shank ensures superior grip, perfect for drilling through stainless steel and other hardened surfaces.
Key Features That Stand Out
- ✓ M42 Cobalt alloy (8% Cobalt) construction for enhanced hardness and exceptional heat resistance.
- ✓ A generous 21-piece set provides a wide range of sizes for maximum versatility.
- ✓ Features a three-flat shank design to prevent bit spin and ensure a secure grip in drill chucks.
- ✓ Optimized for aggressive drilling in stainless steel, cast iron, and other tough metal applications.
- ✓ Engineered to deliver up to 10 times longer life than conventional drill bits.
Why We Recommend It
For those seeking the premium performance of M42 Cobalt without breaking the bank, this 21-piece Bosch set is an outstanding option. It delivers the strength and heat resistance needed for challenging materials while offering a wide array of sizes, making it incredibly versatile and a smart investment for its price point.
Best For
Users who need a comprehensive range of high-performance drill bits for frequent work with stainless steel, hardened steel, and other difficult-to-drill metals, offering excellent value for money.
Pros and Cons
Pros:
- M42 Cobalt ensures superior hardness, heat resistance, and cutting performance.
- Extensive 21-piece set provides great versatility for various projects.
- Three-flat shank design prevents slippage and enhances safety.
- Excellent value for a full set of M42 Cobalt drill bits.
- Highly effective on stainless steel and tough alloys.
Cons:
- Cobalt bits can be more brittle than HSS if excessive pressure is applied.
- Requires proper drilling techniques (speed, coolant) to maximize longevity.
Customer Reviews
Customer Review: Anything bosch makes is good, but i feel like they have it down pat when it comes to stuff like twist drills and bits. The M42 cobalt keeps the drill from getting too hot and also acts as a “lubricant”, both contributing to keeping a sharp cutting edge, giving it quality and ease of use. These factors are important.
Customer Review: This is a great drill bit set. The reason I purchased this set is because I needed to drill and tap a hole in the end of a lawnmower engine crankshaft. Rather than buying just that drill bit I decided to get a whole set, because I knew I would need drill bits again. I decided to go with this set over others due to the positive reviews.
4. M35 Cobalt Drill Bits for Hardened Steel and Stainless Steel, TiAlN Coated
The M35 Cobalt Drill Bits for Hardened Steel and Stainless Steel, TiAlN Coated are engineered for industry-leading durability and efficiency. Combining 5% Cobalt High-Speed Steel with a advanced TiAlN Nano-coating, these bits are built to resist extreme heat and outlast standard bits by a factor of 5X. Their unique triple-flute design ensures faster cutting and superior chip removal, making them perfect for drilling through the toughest metals with precision.
Key Features That Stand Out
- ✓ M35 Cobalt High-Speed Steel (5% Cobalt core) provides exceptional heat resistance up to 1200°F.
- ✓ TiAlN Nano-coating (89HRC hardness) significantly reduces friction and enhances bit longevity.
- ✓ Innovative triple-flute design allows for 40% faster cutting and improved chip removal, preventing clogging.
- ✓ 135° self-centering tip ensures precise hole starts without the need for a pilot hole.
- ✓ Specifically engineered for drilling through hardened steel and stainless steel with speed and efficiency.
Why We Recommend It
These M35 Cobalt bits stand out for their aggressive cutting capability and extreme durability in hardened and stainless steel. The combination of TiAlN coating and the triple-flute design means you get faster, cleaner holes with less effort, making them a top choice for demanding metalworking projects.
Best For
Serious metalworkers, fabricators, and DIYers who regularly work with hardened steel, thick stainless steel, and require bits that can deliver speed, precision, and longevity in challenging materials.
Pros and Cons
Pros:
- M35 Cobalt with TiAlN coating offers extreme hardness and heat resistance for superior lifespan.
- Triple-flute design significantly increases cutting speed and efficient chip evacuation.
- 135° self-centering tip prevents bit walking and ensures precise hole placement.
- Exceptional performance and durability in hardened and stainless steel.
- Reduces the likelihood of bit breakage due to improved chip flow.
Cons:
- Higher investment cost due to advanced materials and design.
- Care must be taken to maintain proper drilling parameters to preserve coating and tip integrity.
Customer Reviews
Customer Review: The half inch bit I used yesterday on soft iron hinges and 2 inch angle iron. Amazed how sharp these bits are! Never seen the most perfect curly shavings as it cut through the metal with ease. Don’t know how long these will last but boy am I impressed so far. These were used in a cordless drill.
Customer Review: The half inch bit I used yesterday on soft iron hinges and 2 inch angle iron. Amazed how sharp these bits are! Never seen the most perfect curly shavings as it cut through the metal with ease. Don’t know how long these will last but boy am I impressed so far. These were used in a cordless drill.
5. Cobalt M35 Twist Jobber Drill Bit Set for Hardened Metal and Stainless Steel 1/16″-3/8″
The Cobalt M35 Twist Jobber Drill Bit Set offers premium performance for drilling through hardened metal and stainless steel, covering a versatile range of 1/16″ to 3/8″ sizes. Made from M35 Cobalt material, these bits boast a hardness of up to 67 HRC, allowing them to cut faster and last significantly longer—up to 12 times more than average HSS titanium coated bits. The full grinding process ensures superior wear resistance and sharpness, all neatly organized in a durable, compartmentalized plastic box.
Key Features That Stand Out
- ✓ Constructed from M35 Cobalt material (5% Cobalt) for exceptional hardness and extended lifespan.
- ✓ Features a hardened full grinding process, enhancing wear resistance and maintaining a sharp cutting edge.
- ✓ Highly effective for drilling through a wide array of hard metals, including stainless steel, cast iron, zinc alloy, and titanium.
- ✓ Promises up to 12 times the life compared to typical HSS titanium-coated drill bits.
- ✓ Comes in a robust, compartmentalized plastic box for organized storage and easy access.
Why We Recommend It
This M35 Cobalt drill bit set provides excellent cutting performance and remarkable durability for drilling through hardened metals and stainless steel. The precision grinding and thoughtful packaging add to its appeal, making it a reliable and long-lasting addition to any toolkit for demanding tasks.
Best For
Individuals who require a durable and sharp set of drill bits for regular work with hardened metals, stainless steel, and other difficult alloys, valuing both performance and organized storage.
Pros and Cons
Pros:
- M35 Cobalt material offers superior hardness, faster cutting, and significantly extended life.
- Full grinding process ensures consistent sharpness and excellent wear resistance.
- Versatile range of sizes suitable for various hardened metal applications.
- Comes with well-designed, compartmentalized packaging for organization.
- Effective on a broad spectrum of tough materials.
Cons:
- The set size range (1/16″-3/8″) might be limited for projects requiring larger bit sizes.
- Cobalt bits, while hard, can be more prone to snapping if misused.
Customer Reviews
Customer Review: Good quality bits even though from offshore. Stay sharp for a long time. They work as expected on hardened metals.
Customer Review: Had a lug nut stripped. Only way off was to drill lug bolt. These bit went right through it with ease. Very impressed with their cutting power.
Complete Buying Guide for Best Drill Bits For Steel
Choosing the best drill bits for steel involves understanding various factors that influence their performance and longevity. Steel is a notoriously tough material, and using the wrong drill bit can lead to frustration, damaged bits, and poor results. This guide will help you navigate the options and make an informed decision.
Essential Factors We Consider
When selecting drill bits for steel, several key characteristics determine their effectiveness:
- Material Composition:
- High-Speed Steel (HSS): Good for general-purpose drilling in softer metals and mild steel, but dulls quickly in harder steel.
- Titanium Nitride (TiN) Coated HSS: HSS bits coated with a layer of titanium nitride. This coating reduces friction, increases hardness, and extends the bit’s life in mild to medium steel.
- Cobalt (M35 or M42): The top choice for drilling into stainless steel, hardened steel, and other tough alloys. Cobalt bits (M35 has 5% cobalt, M42 has 8% cobalt) offer superior heat resistance and hardness, allowing them to maintain a sharp edge even at high temperatures.
- Tip Angle:
- 118-degree point: Common for general-purpose drilling, but can “walk” on harder surfaces.
- 135-degree split point: Ideal for harder materials like steel. This self-centering tip prevents bit walking, allows for faster penetration, and doesn’t require a pilot hole.
- Shank Type:
- Round Shank: Standard for most drills.
- Three-Flat or Hex Shank: Provides a more secure grip in the drill chuck, preventing slippage, especially when drilling tough materials.
- Coatings: Besides TiN, other coatings like Titanium Aluminum Nitride (TiAlN) offer even higher hardness and heat resistance, often found on premium cobalt bits for extreme applications. Black oxide coatings provide some corrosion resistance and slightly reduce friction.
- Set Size and Range: Consider the variety of sizes you need. A larger set might offer more versatility, but a smaller, high-quality set of specific sizes might be more appropriate for specialized tasks.
Budget Planning
While drill bits for steel can range in price, it’s often a case where you get what you pay for. Investing in higher-quality cobalt drill bits or premium coated HSS bits may seem more expensive upfront, but they will last significantly longer, perform better, and save you money in the long run by reducing the need for frequent replacements. For occasional light steel work, a good TiN-coated set might suffice, but for regular or heavy-duty use, cobalt is the way to go.
Final Thoughts
Drilling steel requires patience, the correct technique (like using proper speed and feed rates, and cutting fluid), and most importantly, the right tools. By prioritizing drill bits made from Cobalt or high-quality coated HSS with a 135-degree split point, you’ll be well-equipped to tackle any steel drilling project effectively and efficiently. Always ensure your drill bit is sharp and use appropriate safety gear.
Frequently Asked Questions
Q: What kind of drill bit is best for drilling into steel?
A: Cobalt drill bits (M35 or M42) are generally considered the best for drilling into steel, especially stainless steel and hardened steel. Their high heat resistance and hardness allow them to cut effectively without dulling quickly. For milder steel, Titanium Nitride (TiN) coated HSS bits are a good, more affordable option.
Q: Can I use a regular HSS drill bit for steel?
A: While regular HSS bits can technically drill into mild steel, they will dull quickly, generate excessive heat, and perform inefficiently. They are not recommended for stainless steel, hardened steel, or heavy-duty applications. For better results and bit longevity, it’s always advisable to use TiN-coated HSS or Cobalt bits.
Q: Do I need to use lubricant when drilling steel?
A: Yes, using a cutting lubricant or oil is highly recommended when drilling steel. It significantly helps to reduce friction and heat buildup, which prolongs the life of your drill bit, improves cutting efficiency, and results in cleaner, more precise holes. It also helps in clearing chips from the hole.
Q: What’s the difference between M35 and M42 Cobalt drill bits?
A: Both M35 and M42 are types of Cobalt High-Speed Steel. The primary difference lies in their cobalt content and additional alloying elements. M35 typically contains 5% cobalt, offering excellent hardness and heat resistance. M42 contains a higher percentage of cobalt, usually 8%, along with other elements, making it even harder and more heat-resistant, ideal for extremely tough materials. M42 bits can be slightly more brittle due to their increased hardness.
Q: How can I prevent my drill bit from breaking when drilling steel?
A: To prevent breakage, use the correct type of drill bit for the steel you’re drilling, apply steady and consistent pressure (avoid excessive force), use the appropriate drilling speed (slower for harder metals), always use cutting fluid, and clear chips frequently to prevent overheating and binding. Ensure the workpiece is securely clamped to prevent movement.
Selecting the right drill bits for steel is paramount for achieving professional results and ensuring the longevity of your tools. Our expert-tested recommendations highlight the best options available, from versatile TiN-coated sets to powerful Cobalt bits designed for the toughest jobs. By understanding the features and benefits of each, you can confidently choose the perfect set for your next project. Don’t let tough steel intimidate you; equip yourself with one of these top-performing drill bit sets and experience the difference in precision and ease. Click through our affiliate links today to get the best prices on these exceptional drill bits and elevate your metalworking capabilities!
I’m Darrell Julian, the founder, lead writer, and hands-on welding enthusiast behind ArcWeldingPro.com. With more than 15 years of real-world welding experience, I created this platform to share what I’ve learned in the field, in the shop, and in the heat of the arc.
