Drilling through steel requires more than just a powerful drill; it demands the best steel drilling bits designed for durability, heat resistance, and precision. Whether you’re working on fabrication, automotive repairs, or intricate DIY projects involving challenging metals like hardened steel or stainless steel, selecting the right drill bit can make all the difference between effortless progress and a frustrating, broken mess. Our comprehensive guide cuts through the noise to present the top performers that promise efficiency and longevity. We’ve meticulously reviewed a range of options, focusing on materials like cobalt drill bits and advanced coatings, to help you find the perfect set for your next metal drilling challenge.
Quick Product Comparison
Our Top 5 Best Steel Drilling Bits Reviews – Expert Tested & Recommended
1. DEWALT Titanium Nitride Coated Drill Bit Set, Pilot Point, 21-Piece
The DEWALT Titanium Nitride Coated Drill Bit Set, Pilot Point, 21-Piece is a top contender for drilling through steel with ease and precision. Its advanced Titanium Nitride Coating and innovative pilot point design ensure exceptional performance and longevity, making it a favorite among professionals and DIY enthusiasts alike for daily use with outstanding durability and reliability.
Key Features That Stand Out
- ✓ Titanium Nitride Coating for enhanced durability and reduced friction.
- ✓ Pilot Point Tip starts on contact, preventing walking and ensuring clean, accurate holes.
- ✓ Optimized for drilling through a variety of metals, including steel.
- ✓ 21-piece set provides a comprehensive range of common sizes for versatility.
- ✓ Designed for longer life and superior resistance to heat and wear.
Why We Recommend It
This DeWalt set stands out for its robust construction and innovative pilot point tip. It delivers consistent, clean holes and significantly extends bit life, making it a reliable choice for demanding tasks involving metal drilling. The brand’s reputation for quality and performance further solidifies its recommendation for achieving precise results.
Best For
Professionals and serious DIYers who frequently drill into various metals, including mild and hardened steel, and require a durable, precise, and long-lasting drill bit set for consistent results.
Pros and Cons
Pros:
- Exceptional durability due to Titanium Nitride coating.
- Pilot Point tip prevents walking and ensures precise starts.
- Versatile for a wide range of metal drilling applications.
- Comes in a convenient and organized carrying case.
- Longer lifespan compared to standard HSS bits.
Cons:
- Higher price point than basic HSS sets.
- May still struggle with extremely hard, specialized alloys without proper technique.
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: I’m impressed with the sharpness and longevity of these bits. They cut through steel effortlessly and the pilot point really makes a difference for clean holes. Highly recommend for anyone serious about their tools.
2. Toolant Cobalt Drill Bit Set, TiAlN Coated for Hardened Steel and Stainless Steel (1/16″-1/2″)
The Toolant Cobalt Drill Bit Set, featuring TiAlN coating, is engineered for superior performance when tackling challenging materials like hardened steel and stainless steel. This 21-piece set offers a wide range of sizes, from 1/16″ to 1/2″, for various applications, promising outstanding durability and reliability in professional environments.
Key Features That Stand Out
- ✓ M35 Cobalt Steel construction for high heat resistance and durability, ideal for tough metal.
- ✓ TiAlN (Titanium Aluminum Nitride) Coating increases surface hardness to 89HRC and improves heat resistance, extending bit life.
- ✓ Designed specifically for drilling into hardened steel, stainless steel, and other tough metals.
- ✓ Comprehensive 21-piece set covers sizes from 1/16″ to 1/2″ for versatile use.
- ✓ Fast cutting with exceptional sharpness and efficient chip removal.
Why We Recommend It
For those who regularly encounter extremely tough metals, the Toolant Cobalt set is a game-changer. The combination of M35 cobalt steel and TiAlN coating ensures these bits cut efficiently and maintain their edge much longer than standard bits, making challenging steel drilling jobs significantly easier and more effective.
Best For
Fabricators, mechanics, and advanced DIYers who frequently drill into hardened metals, stainless steel, and other high-strength alloys where standard HSS bits often fail, requiring precision and endurance.
Pros and Cons
Pros:
- Exceptional hardness and heat resistance from TiAlN coating.
- M35 Cobalt steel provides superior strength and longevity.
- Excellent for drilling through hardened steel and stainless steel.
- Good value for a cobalt-coated set with a wide size range.
- Efficient chip removal for smoother and faster drilling.
Cons:
- Cobalt bits can be more brittle than HSS if misused (e.g., incorrect speed/pressure).
- Requires proper cooling for optimal performance in very hard materials.
Customer Reviews
Customer Review: I was skeptical about these at first, but they absolutely shredded through some thick stainless steel I was working on. The TiAlN coating really seems to make a difference. Definitely worth the investment if you’re working with tough metals.
Customer Review: These bits are fantastic for hardened steel! I’ve broken so many other bits on certain projects, but these Toolant cobalt bits hold up. Just remember to use a lubricant and correct drill speed.
3. Best Cobalt M35 High-Speed Steel Drill Bits for Hardened Metals and Stainless Steel
This set of M35 Cobalt High-Speed Steel drill bits offers robust performance for cutting through a variety of hardened metals, including stainless steel. With 13 commonly used sizes, it’s a versatile choice for both professional and home workshops seeking reliable drilling power with outstanding durability and reliability.
Key Features That Stand Out
- ✓ Constructed from M35 Cobalt High-Speed Steel for enhanced strength and heat resistance.
- ✓ 13-piece set with common sizes from 1/16″ to 1/4″, suitable for various tasks.
- ✓ 135-degree split point tip for quick starts and minimal walking, ensuring accuracy.
- ✓ Twist design for efficient chip removal and reduced heat build-up during drilling.
- ✓ Suitable for cutting stainless steel, cast iron, copper, and other tough alloys.
Why We Recommend It
If you’re looking for an affordable yet effective solution for drilling hardened metals, this M35 Cobalt set delivers. Its design promotes quick and efficient drilling, making it a solid budget-friendly option without compromising too much on durability for challenging materials like stainless steel.
Best For
DIY enthusiasts and tradespeople needing a cost-effective set of cobalt bits for occasional to moderate use on stainless steel, hardened metals, and general metalworking tasks, where value and performance are key.
Pros and Cons
Pros:
- Excellent performance on hardened metals for its price point.
- M35 Cobalt steel offers good durability and heat resistance.
- 135-degree split point ensures accurate drilling.
- Versatile for various metal types.
- More economical than premium cobalt sets.
Cons:
- Durability may not match higher-end, coated cobalt bits for extreme continuous use.
- The 13-piece set might not cover all specialized sizes for some users.
Customer Reviews
Customer Review: I had a use case where a machine screw had broken off in a location that wasn’t easy to access. I decided versus pulling the piece of equipment apart to improve access, I’d spend the money on a set of these with the hopes it would catch as I was drilling out the broken off screw. The screw broke cleanly and these bits helped me extract it without further damage. Impressed with the cutting power for the price!
Customer Review: I purchase this set just under a year ago. I have not use these drill bits but a couple of times and 4 have already broken. I contacted Macxcoip and they immediately reached out to address my concerns and offered a full refund or replacement. While the initial durability was a slight issue, their customer service was excellent, and I’m happy with the resolution.
4. NordWolf 5-Piece M35 Cobalt Stubby Drill Bit Set for Stainless Steel, 1/4″ Hex Shank.
The NordWolf 5-Piece M35 Cobalt Stubby Drill Bit Set is specifically designed for accessing tight spaces and drilling into tough materials like stainless steel. Its stubby length and 1/4″ hex shank make it ideal for impact drivers and compact drills, offering precision and durability for daily use with outstanding reliability.
Key Features That Stand Out
- ✓ M35 Cobalt steel precision ground drill bits for extra durability and long lifetime.
- ✓ Stubby drill bits measure from 1.84 to 2.32-inch only, allowing access to hard-to-reach and tight spaces.
- ✓ 1/4″ Hex Shank for quick changes and compatibility with impact drivers.
- ✓ 135-degree split point multi-blade design for quick, clean starts without walking.
- ✓ Multi-Purpose Use: Suitable for drilling stainless steel and various hardened metals such as cast iron, titanium, bronze, aluminium, etc.
Why We Recommend It
This NordWolf set is a specialist’s tool, perfectly suited for situations where standard-length bits are too long. Its robust M35 Cobalt construction combined with the compact, hex-shank design makes it incredibly effective for precise drilling in tough materials within limited spaces, proving essential for specialized jobs.
Best For
Plumbers, electricians, automotive technicians, and DIYers who need to drill into hard metals like stainless steel in tight or confined spaces, especially when using impact drivers or compact drill/drivers.
Pros and Cons
Pros:
- Ideal for tight spaces due to stubby length.
- M35 Cobalt steel offers excellent durability for tough metals.
- 1/4″ hex shank for quick changes and impact driver compatibility.
- 135-degree split point ensures accurate and fast drilling.
- Resistant to high temperatures generated during drilling.
Cons:
- Limited range of sizes in the 5-piece set.
- Not suitable for applications requiring longer drilling depths.
Customer Reviews
Customer Review: Ok drill bits for medium jobs, get the job done but don’t be to rough or will brake
Customer Review: A must have especially for tight areas. I had to do out a bolt that broke off when replacing a thermostat. This thing cut thru like butter. Make sure tonuse steady pressure and a drill set on slow speed so it can grip and you will be thru in no time. Definitely recommend.
5. Best M35 Cobalt Steel Drilling Bits for Hardened Metal and Stainless Steel, TiAlN Coated.
This advanced set of M35 Cobalt Steel drilling bits is engineered for maximum performance and longevity when drilling through the toughest metals, including hardened steel and stainless steel. Featuring a TiAlN coating and a unique triple-flute design, these bits promise industry-leading durability and speed, making them perfect for daily use with outstanding reliability.
Key Features That Stand Out
- ✓ 🔥 Industry-Leading Durability: M35 Cobalt High-Speed Steel with 5% Cobalt core resists 1200°F heat, outlasting standard bits by 5X in hardened steel.
- ✓ ⚡️ Triple-Flute Revolution: Special 3-flute design cuts faster with 40% better chip removal, eliminating clogging and reducing breakage – perfect for continuous, heavy-duty work.
- ✓ 🎯 Precision Engineered for Pros: TiAlN Nano-coating (89HRC hardness) + 135° self-centering tip bores through 1/4″ stainless steel in 8 seconds flat.
- ✓ Exceptional resistance to wear and abrasion for prolonged bit life.
- ✓ Optimized for professional-grade metal drilling in the most demanding materials.
Why We Recommend It
For those who demand the absolute best in performance and longevity for heavy-duty metal drilling, this TiAlN-coated M35 Cobalt set is an outstanding choice. Its innovative design and premium materials make short work of even the most stubborn hardened metals, delivering unparalleled speed and durability.
Best For
Professional welders, machinists, fabricators, and serious contractors who regularly drill into extremely hard and thick stainless steel, hardened alloys, and other difficult metals, where efficiency and bit lifespan are paramount.
Pros and Cons
Pros:
- Unmatched durability and heat resistance for hardened metals.
- TiAlN coating significantly enhances lifespan and cutting performance.
- Triple-flute design ensures rapid cutting and efficient chip evacuation.
- 135-degree self-centering tip for precise and fast drilling.
- Proven to cut through tough materials quickly (e.g., 1/4″ stainless steel in 8 seconds).
Cons:
- Premium price point reflects advanced technology and materials.
- Requires proper drilling techniques (speed, pressure, cooling) to maximize benefits.
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: These bits are incredibly sharp and cut through even thick steel like butter. I’ve used them on several projects involving tough metal, and they show no signs of dulling. Definitely a professional-grade set that lives up to its claims.
Complete Buying Guide for Best Steel Drilling Bits
Essential Factors We Consider
Choosing the best steel drilling bits involves understanding several key factors that dictate their performance and longevity. First, the material is paramount: High-Speed Steel (HSS) bits are suitable for mild steel, but for harder alloys, you’ll need Cobalt (M35 or M42) or even Carbide-tipped bits, which offer superior heat and abrasion resistance. Second, advanced coatings like Titanium Nitride (TiN), Titanium Carbonitride (TiCN), or Titanium Aluminum Nitride (TiAlN) are crucial. These coatings increase surface hardness, reduce friction, and dissipate heat, significantly extending bit life when drilling tough metals like stainless steel and hardened steel. Third, pay attention to the tip design; a 135-degree split point tip is highly recommended as it prevents “walking” at the start of the hole and allows for self-centering, providing quicker, more accurate starts without a pilot hole. Fourth, consider the shank type: standard round shanks are common, but hex shanks offer better grip and prevent slippage, ideal for quick-change chucks and impact drivers. Lastly, evaluate the set size and range to ensure it covers the diameters you’ll frequently need, and always opt for bits from reputable brands known for quality manufacturing.
Budget Planning
Investing in higher-quality steel drilling bits, especially cobalt or TiAlN-coated ones, can initially seem more expensive, but it often saves money in the long run by preventing frequent replacements and project delays. While the upfront cost might be higher than basic HSS sets, their superior durability, cutting efficiency, and extended lifespan make them a worthwhile investment for anyone regularly working with tough metals. Consider your usage frequency and the types of materials you’ll be drilling most often to strike the right balance between initial cost and long-term performance.
Final Thoughts
Ultimately, choosing the best steel drilling bits involves matching the bit’s capabilities with the specific demands of your project. For occasional use on mild steel, a good HSS set might suffice. However, for serious work involving hardened steel, stainless steel, or exotic alloys, cobalt drill bits, particularly those with advanced coatings like TiAlN, are indispensable. These premium bits ensure you achieve clean holes, maintain long tool life, and complete your tasks efficiently. Always remember to use appropriate drilling techniques, including proper speed, firm pressure, and adequate cooling, to maximize performance, extend bit life, and ensure safety.
Frequently Asked Questions
Q: What is the best type of drill bit for hardened steel?
A: For hardened steel, cobalt drill bits (M35 or M42) are generally considered the best. They contain a higher percentage of cobalt, which increases their heat resistance and hardness, allowing them to cut effectively through tougher materials where standard HSS bits would quickly dull or break.
Q: How do coatings like TiN and TiAlN improve drill bits?
A: Coatings such as Titanium Nitride (TiN) and especially Titanium Aluminum Nitride (TiAlN) significantly enhance drill bits by increasing their surface hardness, reducing friction, and improving heat resistance. This results in faster cutting, reduced wear, and a much longer lifespan, particularly when drilling abrasive or high-strength metals.
Q: Can I use a regular drill bit on stainless steel?
A: While a standard High-Speed Steel (HSS) drill bit might work on thin or softer grades of stainless steel, it will quickly dull due to stainless steel’s work-hardening properties. For consistent results and to prevent bit breakage, it is highly recommended to use cobalt drill bits or TiN/TiAlN-coated HSS bits when drilling stainless steel.
Q: What drill speed should I use for drilling steel?
A: When drilling steel, especially hardened steel or stainless steel, it’s generally best to use a slower drill speed with firm, consistent pressure. High speeds generate excessive heat, which can quickly dull and destroy your drill bit. Always consult a speed chart or the drill bit manufacturer’s recommendations for optimal results.
Q: Why is a 135-degree split point tip important for drilling steel?
A: A 135-degree split point tip is crucial for drilling steel because it eliminates the need for a pilot hole by preventing the drill bit from “walking” or wandering at the start of the cut. This self-centering design allows for immediate penetration and creates a cleaner, more accurate hole from the outset, reducing effort and improving precision.
Choosing the best steel drilling bits is essential for efficiency, precision, and safety when working with metals. Whether you’re tackling mild steel or challenging hardened alloys and stainless steel, selecting the right bit material, coating, and tip design can make all the difference. Our top picks, from the versatile DEWALT Titanium Nitride Coated Drill Bit Set to the high-performance TiAlN-coated Cobalt bits, offer superior durability and cutting power for various applications. We encourage you to explore these options and invest in quality tools that will withstand the toughest drilling challenges and ensure your projects are completed with professional results.
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.
