Best Drills for Stainless Steel: Top Cobalt and HSS Sets for Hard Metals
Drilling stainless steel requires bits that stay sharp, resist heat, and maintain accuracy under tough conditions. The best drills for stainless steel combine cobalt or M42 high-speed steel (HSS) with precise tip geometry, robust shanks, and durable coatings to reduce wear and wandering. The following five Amazon options represent top-performing cobalt and HSS sets designed to deliver clean holes in stainless steel, cast iron, and other hard metals, while offering varied sizes, cases, and features for both professionals and serious hobbyists. Below you’ll find a quick comparison and detailed product sections to help you choose the right set for your projects.
| Product | Brand | Material | Case Included | |
|---|---|---|---|---|
| Bosch Co14B 14-Piece | Bosch | Cobalt M42 | Yes | Includes durable M42 cobalt jobber-length bits; high-heat resistance |
| Stroton 13-Piece | STROTON | Premium True 5% Cobalt Steel | No | Heavy-duty design for stainless steel and hard metals |
| NordWolf 5-Piece Stubby | NordWolf | M35 Cobalt | Yes | 1/4″ hex shank; compact length for tight spaces |
| Macxcoip 13-Piece | MACXCOIP | M35 Cobalt | Yes | Index storage case; 13 sizes from 1/16″ to 1/4″ |
| Crosstar 21-Piece | Crosstar | M35 Cobalt with TiAlN coating | No | Three-flute design; TiAlN-coated for extra durability |
Bosch Co14B 14-Piece Cobalt Drill Bit Set
The Bosch Co14B offers cobalt M42 bits in a 14-piece assortment, designed for durability in stainless steel and other hard metals. The included case provides organized storage for portable work.
- Cobalt M42 drill bit – provides upgraded M42 Cobalt Cobalt jobber-length bits designed for durability, high heat resistance and Hardened surface for stainless steel, cast iron, titanium, and light-gauge metal and aluminum
- Enhanced M42 alloy material – contains 8% Cobalt alloy that delivers 10x life vs. Standard bits
- High-heat resistant bits – withstand high-temperature applications for extended periods of time
NordWolf M35 Cobalt Stubby Drill Bits
NordWolf’s stubby set is built for hard metals and tight spaces. The bits use a precise M35 cobalt core with a 135° split point for self-centering and fast drilling, and the pieces all feature a 1/4-inch hex shank to fit quick-change chucks and drivers.
- High Quality: M35 Cobalt steel precision ground drill bits for extra durability and long lifetime
- Efficient Design: Stubby drill bits measure from 1.84 to 2.32-inch only, allowing access to hard-to-reach and tight spaces. 135° split point for self-centering and fast drilling
- Multi-Purpose Use: Suitable for drilling stainless steel and various hardened metals such as cast iron, titanium, bronze, aluminium, etc. All drill bits come with one piece 1/4-inch hex shank compatible with standard and quick change chucks and drivers
Macxcoip 13-Piece Cobalt Drill Bit Set
The Macxcoip 13-piece set provides a broad range (1/16″ to 1/4″) of M35 cobalt bits for hardened metals and common plastics and woods. Featuring a 135° point tip and a quick, efficient cutting action, these bits are designed for fast, self-centering drilling with minimal wandering.
- Various Sizes: 13 bits include 1/16″, 5/64″, 3/32″, 7/64″, 1/8″, 9/64″, 5/32″, 11/64″, 3/16″, 13/64″, 7/32″, 15/64″, 1/4″
- M35 Cobalt Drill Bit: The M35 cobalt drill bit is a durable, sharp and robust drill bit suitable for cutting stainless steel, iron castings, copper, aluminum and other soft metals as well as plastics, wood etc
- Quick and Efficient: The cobalt drill bit set can be used effectively on most soft and hard objects, with a 135 degree point tip and twist design for faster cutting, self-centering to prevent walk-off and faster chip removal
Crosstar M35 Cobalt Drill Bit Set
The Crosstar set features M35 cobalt bits with a TiAlN coating and a three-flute design for faster cutting and improved chip removal. The 135° self-centering tip bores through stainless steel quickly, making it suitable for heavy-duty metalworking and automotive tasks.
- Industry-Leading Durability: M35 Cobalt High-Speed Steel with 5% Cobalt core resists 1200°F heat, outlasting standard bits by 5X in hardened steel, stainless steel, and cast iron drilling
- Triple-Flute Revolution: Special 3-flute design cuts faster with 40% better chip removal, eliminating clogging and reducing breakage
- Precision Engineered for Pros: TiAlN Nano-coating (89HRC hardness) + 135° self-centering tip bores through 1/4″ stainless steel in 8 seconds flat – zero wandering, no pilot holes needed
Buying Guide
When selecting drill bits for stainless steel, consider how you will use them most often, what metals you typically encounter, and how you prefer to work. The following factors help distinguish the best sets for different needs:
- Material and heat resistance: M35 cobalt bits (5% cobalt) outperform standard HSS in hot alloys, and M42 cobalt bits offer even higher heat resistance. For frequent drilling in stainless steel, choose sets with cobalt content and a design that minimizes heat buildup.
- Tip geometry and centering: 135° split-point tips reduce wandering and improve precision. Self-centering tips are especially helpful when starting holes in hard metals without pilot holes.
- Coatings and longevity: TiAlN coatings help extend tool life by reducing wear and friction, particularly in stainless steel and cast iron. Consider coatings if you drill frequently in hard metals.
- Shank type and compatibility: Quick-change hex shanks (1/4″) work well with most impact drivers and quick-change chucks. If you use a standard drill press or hand drill, ensure the shank fits your chuck size.
- Set size and range: For a broader project mix, larger sets (13–21 pieces) cover more sizes and reduce the need to switch bits often. For compact projects, a smaller stubby set improves access in tight spaces.
- Case and storage: An index or organized case protects bits and simplifies transport. If you work on-site, a durable case helps keep tools organized and reduces loss.
- Application breadth: Some sets include very large or very small bits, enabling drilling through various metal gauges, plastics, and wood. Assess whether you need full-range coverage or a more focused subset.
In sum, for stainless steel, select a cobalt-containing set with robust tip geometry and a protective coating, and match the set size to your typical project scope. Stubby bits suit tight spaces, while larger sets provide flexibility for many jobs. Always check whether the bits fit your drill’s chuck and whether the case helps keep your toolkit organized for on-site work or shop projects.