Welcome to our comprehensive guide on the best cobalt drill bit set! When it comes to tackling tough drilling tasks, whether you’re working with hardened metals, stainless steel, or cast iron, standard drill bits often fall short. That’s where cobalt drill bits shine, offering superior hardness, heat resistance, and durability. Engineered with an alloy of steel and a percentage of cobalt (typically 5-8%), these bits maintain their sharpness at much higher temperatures, making them indispensable for professional tradespeople and serious DIYers alike. In this article, we’ve meticulously reviewed the top cobalt drill bit sets on the market, evaluating their performance, longevity, and overall value to help you find the perfect set for your needs.
Quick Product Comparison
Our Top 5 Best Cobalt Drill Bit Set Reviews – Expert Tested & Recommended
1. BOSCH 14-Piece Cobalt M42 Metal Drill Bit Set with Three-Flat Shank for Tough Metals
The BOSCH 14-Piece Cobalt M42 Metal Drill Bit Set is engineered for extreme durability and superior performance in the toughest metals. Featuring upgraded M42 Cobalt jobber-length bits, this set is designed to withstand high-heat applications and provide a significantly extended lifespan compared to standard bits. Its three-flat shank ensures a secure grip in drill chucks, preventing slippage during heavy-duty tasks.
Key Features That Stand Out
- ✓ Enhanced M42 Alloy Material: Contains 8% Cobalt alloy for superior hardness and heat resistance.
- ✓ Extended 10x Life: Delivers significantly longer lifespan compared to conventional drill bits.
- ✓ High-Heat Resistant Bits: Capable of withstanding extreme temperatures, ideal for continuous drilling.
- ✓ Three-Flat Shank: Provides a secure, non-slip grip in the drill chuck for improved control and safety.
- ✓ Hardened Surface: Specifically designed for drilling through stainless steel and other challenging materials.
Why We Recommend It
We highly recommend the BOSCH M42 Cobalt set for its exceptional ability to tackle demanding drilling applications in various tough metals. The M42 cobalt alloy, combined with the three-flat shank design, offers reliability and precision that serious users will appreciate. It’s a fantastic investment for longevity and consistent high performance.
Best For
This set is best for professionals and advanced DIY enthusiasts who frequently drill into hardened metals, stainless steel, cast iron, and other high-strength alloys where heat and wear are major concerns.
Pros and Cons
Pros:
- Excellent heat resistance prevents dulling.
- Superior durability and extended tool life (10x compared to standard bits).
- Three-flat shank ensures stable drilling without slippage.
- Effectively drills through very hard materials like stainless steel.
Cons:
- Higher price point than standard HSS sets.
- Limited to 14 pieces, may require additional sizes for specific projects.
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 really make a difference.”
Customer Review: “This is a great drill bit set. I needed to drill and tap a hole in a lawnmower engine crankshaft. Rather than buying just that one drill bit, I decided to get a whole set, knowing I would need drill bits again. I decided to go with this set over others because of Bosch’s reputation for quality in tough applications, and it delivered perfectly.”
2. Champion Cutting Tool Brute Platinum 29-Piece Cobalt Drill Bit Set, 1/16-1/2″ Mechanics Length
The Champion Cutting Tool Brute Platinum 29-Piece Cobalt Drill Bit Set is an exceptional choice for those needing robust and reliable bits for demanding applications. Designed for maximum performance, these bits offer significantly longer life and faster drilling speeds compared to traditional cobalt bits. Their unique XL28 composition allows for flexibility, reducing the risk of chipping or snapping.
Key Features That Stand Out
- ✓ Drill 3x Longer and 2x Faster: Outperforms competitors and even other cobalt drills in longevity and speed.
- ✓ Better Than Cobalt (XL28): Engineered to flex when traditional cobalt drills chip or snap, enhancing durability.
- ✓ Accurate Drilling: Features a 135-degree split point and tapered web geometry for precise starts and efficient chip evacuation.
- ✓ Mechanics Length: Reduced overall length provides added strength and rigidity, ideal for heavy-duty tasks.
- ✓ Flatted Shanks: Ensures fast and secure chucking in keyless power tools, preventing slippage.
Why We Recommend It
This Champion Cutting Tool set stands out for its innovative XL28 material which addresses a common issue with cobalt bits: brittleness. The combination of speed, durability, and a wide range of sizes makes it an indispensable asset for any serious toolkit. It truly offers a step up in performance for tough metal drilling.
Best For
This set is best for professional mechanics, fabricators, and serious metalworkers who require superior performance and longevity when drilling through hard alloys, stainless steel, and other challenging materials.
Pros and Cons
Pros:
- Enhanced flexibility reduces breakage, improving lifespan.
- Significantly faster drilling speeds than standard cobalt bits.
- Excellent precision with 135-degree split point.
- Wide range of sizes (29 pieces from 1/16″ to 1/2″).
Cons:
- Premium price reflects its professional-grade quality.
- Storage case could be more robust for heavy shop use.
Customer Reviews
Customer Review: “I’ve drilled a bazillion holes in every kind of material you can think of over more than 65 years of being an automotive technician, and used up my share of drill bits. I’ve learned to recognize good ones from bad ones, and I’d have to say that these appear to be among the best quality around. Beautiful bits!”
Customer Review: “As an experienced technician, I consistently need reliable tools. These Champion Brute Platinum bits live up to their name. They cut through hardened steel with impressive speed and stay sharp much longer than any other set I’ve owned. The mechanics length is perfect for getting into tight spots.”
3. Best Cobalt Drill Bit Set for Drilling Hardened Metals, Stainless Steel, and Cast Iron
This M35 Cobalt Drill Bit Set offers an excellent balance of affordability and performance for tackling hardened metals, stainless steel, and cast iron. With a comprehensive selection of 29 common sizes, it provides great versatility for a wide range of projects. The M35 cobalt alloy ensures a durable, sharp, and robust cutting edge, making quick work of tough materials.
Key Features That Stand Out
- ✓ Comprehensive 29-Piece Set: Includes a wide range of sizes from 1/16″ to 1/2″ for various tasks.
- ✓ M35 Cobalt Drill Bit: Made with a durable, sharp, and robust cobalt alloy suitable for demanding cuts.
- ✓ Quick and Efficient Drilling: Features a 135-degree point tip and twist design for fast penetration and effective chip clearing.
- ✓ Versatile Application: Designed for effective use on both soft and hard objects, including stainless steel and iron castings.
- ✓ Exceptional Value: Offers robust performance typically found in more expensive sets at a budget-friendly price.
Why We Recommend It
For those seeking a reliable cobalt drill bit set without breaking the bank, this 29-piece M35 set is an outstanding choice. It provides the necessary strength and heat resistance for drilling hardened metals and stainless steel, offering great value and versatility for its price point. It’s a solid performer for general-purpose metalworking.
Best For
This set is best for hobbyists, homeowners, and those who need a capable set of cobalt drill bits for occasional to moderate use on tough materials without a significant investment.
Pros and Cons
Pros:
- Excellent value for a comprehensive M35 cobalt set.
- Good performance on hardened steel, stainless steel, and cast iron.
- Wide range of sizes covers most common drilling needs.
- 135-degree split point prevents walking and allows for quick starts.
Cons:
- Durability may not match premium brands under constant heavy use.
- Some users have reported occasional breakage, though support is responsive.
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 down easily with these bits, I was very impressed.”
Customer Review: “I purchased this set just under a year ago. I have not used these drill bits but a couple of times, and 4 have already broken. Update: Macxcoip Cobalt Drill Bits set seller reached out to address any issues or concerns with my satisfaction with the product I received. They offered a full refund or to replace the set, which shows good customer service despite the initial issue.”
4. Milwaukee 23-Piece RED Helix Cobalt Drill Bit Set for Tough Metal Drilling
The Milwaukee 23-Piece RED Helix Cobalt Drill Bit Set is specifically engineered for tough metal drilling, featuring the brand’s signature RED Helix design. This innovative flute geometry and a precision ground 135-degree split point tip allow for faster material removal and reduced heat buildup, ensuring extended bit life and efficient drilling performance. Milwaukee’s reputation for quality tools shines through in this robust cobalt set.
Key Features That Stand Out
- ✓ RED Helix Design: Optimized flute design allows for rapid chip ejection, minimizing heat and wear.
- ✓ 135-Degree Split Point: Prevents walking on contact and ensures precise, quick starts without pre-drilling.
- ✓ Cobalt Alloy Construction: Provides superior heat resistance and strength for drilling through hard metals and alloys.
- ✓ Enhanced Durability: Engineered to withstand the rigors of heavy-duty applications and extend bit lifespan.
- ✓ Comprehensive 23-Piece Set: Offers a good selection of sizes for various metalworking tasks.
Why We Recommend It
Milwaukee’s RED Helix Cobalt set is a fantastic option for those who value efficiency and durability. The unique flute design combined with cobalt material significantly improves drilling speed and bit longevity, especially in challenging environments. It’s a reliable choice for consistent, high-quality performance.
Best For
This set is best for trade professionals, electricians, plumbers, and general contractors who frequently encounter demanding metal drilling situations and require bits that can withstand continuous heavy use.
Pros and Cons
Pros:
- RED Helix design improves chip removal and reduces heat.
- Excellent durability and heat resistance for hard metals.
- 135-degree split point ensures accurate, no-walk starts.
- Reputable Milwaukee quality and reliable performance.
Cons:
- Premium price compared to some other cobalt sets.
- Plastic case, while functional, could be more robust.
Customer Reviews
Customer Review: “These Milwaukee RED Helix cobalt bits are absolute workhorses. I’ve used them extensively on structural steel and thick stainless, and they just keep cutting. The helix design really does make a difference in how quickly they clear chips, which helps prevent overheating. Highly recommend for any serious metalworker.”
Customer Review: “As a professional fabricator, I rely on my tools to perform under pressure. This Milwaukee cobalt set has been fantastic. The bits hold their edge remarkably well, even when drilling dozens of holes in hardened materials. It’s a solid investment for anyone doing heavy-duty drilling.”
5. Champion Cutting Tool 29 Piece 1/16″-1/2″ Cobalt Jobber Drill Bit Set, 135 Deg Split Point
The Champion Cutting Tool 29 Piece 1/16″-1/2″ Cobalt Jobber Drill Bit Set is designed for superior performance and durability in industrial applications. Featuring a 135-degree split point and advanced XL5 cobalt alloy, these bits promise to drill significantly longer and faster than conventional cobalt options. The addition of NOMO surface treatment further enhances tool life, penetration, and flexibility, making this set a powerhouse for challenging drilling tasks.
Key Features That Stand Out
- ✓ Drill 3x Longer and 2x Faster: Engineered for extended life and quicker material penetration.
- ✓ XL5 Cobalt Alloy: Designed for flexibility to resist chipping and snapping, a common issue with standard cobalt.
- ✓ NOMO Surface Treatment: Enhances tool life, speeds up penetration, and improves overall flexibility.
- ✓ 135-Degree Split Point: Ensures immediate, accurate starts without pilot holes and prevents bit walking.
- ✓ Premium High-Speed Steel Base: Provides a strong foundation for the cobalt alloy, improving overall bit integrity.
Why We Recommend It
This Champion Cutting Tool set offers a professional-grade solution for intensive drilling. The combination of the specialized XL5 cobalt, NOMO treatment, and a wide array of sizes makes it an extremely versatile and reliable choice for tasks requiring exceptional bit strength and endurance. It’s a top-tier choice for consistent, high-volume metal drilling.
Best For
This set is best for industrial users, metal fabricators, machinists, and anyone requiring a heavy-duty, long-lasting cobalt drill bit set for continuous and demanding use in a wide range of ferrous and non-ferrous metals.
Pros and Cons
Pros:
- Exceptional durability due to XL5 cobalt and NOMO treatment.
- Significantly faster drilling and longer lifespan.
- Accurate and clean holes thanks to the 135-degree split point.
- Comprehensive size range (29 pieces) for versatility.
Cons:
- High initial investment, but justified by performance and longevity.
- Requires proper drilling techniques (e.g., cooling) to maximize bit life.
Customer Reviews
Customer Review: “Having worked with metal for decades, I’ve used countless drill bits. This Champion set is truly outstanding. The XL5 cobalt combined with the NOMO coating makes a noticeable difference in how effortlessly they cut through even tough alloys. They stay sharp for a surprisingly long time, making them worth every penny.”
Customer Review: “I was skeptical about the claims of ‘3x longer’ and ‘2x faster’, but these bits deliver. I’ve been drilling into thick stainless steel exhaust parts, and they hold up brilliantly. The precision of the 135-degree point is excellent for starting holes accurately. This is now my go-to set for serious metal drilling.”
Complete Buying Guide for Cobalt Drill Bit Set
Essential Factors We Consider
Choosing the best cobalt drill bit set involves more than just picking the first one you see. Here are the critical factors we consider:
- Cobalt Percentage (M35 vs. M42): Cobalt drill bits are typically made from High-Speed Steel (HSS) with an alloy of 5% (M35) or 8% (M42) cobalt. M42 cobalt offers greater hardness and heat resistance, making it ideal for extremely tough materials. M35 is a great all-rounder for most challenging applications.
- Heat Resistance: Cobalt’s primary advantage is its ability to retain hardness at high temperatures. Look for bits specifically designed to withstand prolonged heat generated during drilling in hard metals.
- Durability and Lifespan: A good cobalt bit should last significantly longer than standard HSS bits, especially when drilling materials like stainless steel or hardened steel. Features like advanced alloy compositions (e.g., XL28, XL5), surface treatments (e.g., NOMO), and flute designs contribute to enhanced durability.
- Point Angle and Geometry: A 135-degree split point is highly recommended as it prevents “walking” or wandering at the start of the hole, allowing for precise, quick starts without a pilot hole. Optimized flute geometry (like Milwaukee’s RED Helix) aids in efficient chip evacuation, reducing heat and prolonging bit life.
- Shank Design: Three-flat shanks or flatted shanks provide a secure grip in drill chucks, preventing slippage, especially during high-torque applications.
- Set Composition and Sizes: Consider the range of sizes included in the set. A comprehensive set (e.g., 29 pieces from 1/16″ to 1/2″) offers greater versatility for different project requirements.
- Case Quality: While secondary, a durable and well-organized case protects your investment and makes finding the right bit easier.
Budget Planning
Cobalt drill bits are generally more expensive than their HSS counterparts, but their performance and longevity often justify the investment, especially if you regularly work with tough materials. When planning your budget:
- Entry-Level (Budget-Friendly): You can find decent M35 cobalt sets that offer good performance for occasional use on hardened metals and stainless steel. These are a great starting point for serious DIYers.
- Mid-Range: In this category, you’ll find more robust M35 or even some M42 sets with improved durability and features like better flute designs. These are suitable for frequent use and more demanding projects.
- Premium/Professional-Grade: These sets, often featuring M42 cobalt, advanced alloy compositions, and specialized treatments, are designed for continuous, heavy-duty industrial or professional use. They represent a significant investment but offer unparalleled performance and lifespan.
Remember, buying a cheaper set that quickly dulls or breaks will cost you more in the long run through replacements and lost time. Invest in quality where it counts.
Final Thoughts
Investing in a high-quality cobalt drill bit set is crucial for anyone serious about working with metal. These bits are not just tools; they are an investment in efficiency, precision, and safety. By considering the cobalt percentage, heat resistance, durability, and specific design features, you can select a set that will perform reliably and extend your capabilities in handling the most challenging drilling tasks. Always remember to use appropriate cutting fluid and drilling techniques to maximize the life and performance of your cobalt bits.
Frequently Asked Questions
Q: What is the main difference between HSS and cobalt drill bits?
A: The main difference lies in their material composition and heat resistance. HSS (High-Speed Steel) bits are good for general-purpose drilling, but cobalt drill bits (typically HSS with 5-8% cobalt alloy) offer superior heat resistance, hardness, and wear resistance. This makes cobalt bits ideal for drilling hardened metals, stainless steel, cast iron, and other abrasive materials where HSS bits would quickly dull or fail due to heat.
Q: Can I use cobalt drill bits in a regular hand drill or drill press?
A: Yes, cobalt drill bits can be used in both hand drills and drill presses. For optimal performance and to prolong bit life, it’s recommended to use a drill press for precise control and consistent pressure, especially when drilling through very hard materials. Always use a stable setup and apply constant, firm pressure with a lower RPM, and use a cutting lubricant.
Q: Do I need to use cutting fluid with cobalt drill bits?
A: While cobalt drill bits are designed to withstand high heat, using a cutting fluid or lubricant is highly recommended. Lubrication helps to dissipate heat even further, reduce friction, clear chips more effectively, and significantly extend the lifespan of your bits. It also results in a cleaner cut and reduces the chances of work hardening the material.
Q: How do I properly care for my cobalt drill bit set?
A: To care for your cobalt drill bits, always use appropriate speeds and feed rates for the material you are drilling, and use cutting fluid. After use, clean the bits thoroughly to remove any metal particles or residue. Store them in their original case or a dedicated bit organizer to prevent damage to the cutting edges. If a bit becomes dull, it can often be resharpened, though this requires specialized equipment and skill.
Q: What does “M35” or “M42” refer to in cobalt drill bits?
A: “M35” and “M42” are common designations for the type of High-Speed Steel used in the manufacture of cobalt drill bits. M35 typically contains 5% cobalt, while M42 contains 8% cobalt. The higher cobalt content in M42 bits provides greater hardness, higher abrasion resistance, and better heat resistance, making them more suitable for extremely tough and abrasive materials, though they can also be more brittle.
Selecting the best cobalt drill bit set is a crucial decision for anyone serious about metalworking. Our comprehensive review and buying guide aim to simplify this choice by highlighting top-performing sets like the BOSCH M42, Champion Brute Platinum, and Milwaukee RED Helix, each offering distinct advantages for different users and applications. Whether you’re frequently drilling hardened metals, stainless steel, or cast iron, a quality cobalt set will significantly enhance your capabilities and the longevity of your tools. Don’t compromise on quality when it comes to tackling tough materials; choose a set that promises durability, efficiency, and precision.
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.
