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We also keyed in on bits with 135-degree points as the recommended angle for efficient drilling into hard metal at the required lower speed and higher pressure. Other variables, such as split or pilot point, flat or 3-flat shank, or various coatings held lower priority. Lastly, we factored in top brand names, which often equate to greater consistency and availability.

The 3-flat shank prevented bit slippage in the chuck and eliminated most snags in the drill work when excessive pressure was applied. The heavy-duty plastic carry case was easy to use and light enough to tote in a tool bag. Overall, it’s a nice all-purpose choice for everyday use with stainless steel and most other metals.

While the Stroton M42 cobalt bits feature round shanks, which can allow slippage in the chuck, we did not experience any slippage during tests, possibly thanks to the unusual low-profile stepped split-point design. Unlike the more pronounced pilot points on other bits we tested, the low-profile Stroton tips featured a three-step tip that seemed to penetrate faster and smoother than other designs, with or without a center punch starting point.

Metal is difficult to work with if you don’t have the proper tools. When drilling for a metalworking project, specific drill bits are required to ensure you can fully cut through the material. While some drill bits that work on wood and plastic also work with soft metals, thicker metals require different drill bit types. To help you determine the best drill bit for your project, we put together this list of the best drill bits for metal on the market.

Twist bits, or HHS bits, are a common drill bit type that can work with various materials, including metal, wood, and plastic. However, finding an HSS or cobalt twist bit is essential, as they are designed to withstand the heat generated during metal drilling.

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You should always wear eye protection, such as safety glasses, when drilling, regardless of material. Additionally, avoid wearing loose clothing, and consider also wearing ear protection.

Customers who liked this product were impressed with its wide range of bits, its ability to work on hard metals, such as titanium, and its longevity and durability. However, our team found some customers who said the bits were not well labeled and others who said the bits dulled quickly.

Stainless steel is an extremely hard material. Low-carbon steel bits, like those used to drill into wood, do not perform when applied to stainless steel. Therefore, a drill bit for use with stainless steel must be harder than the steel itself. One way that manufacturers achieve this hardness is by infusing materials that facilitate penetration and protect against overheating.

In some project settings, a single step drill bit can replace an entire set of twist bits. Step bits offer the advantage of fast, clean precision drilling into thin stainless steel or sheet metal without the need to change between different bit sizes. Each one of the three cobalt step drill bits in Milwaukee’s set is engineered to drill up to 1,000 holes into 14-gauge steel. They feature a rapid strike tip for fast starts without a center punch, elongated dual flutes to minimize heat, and finer step increments for smoother operation. Hole sizes are laser engraved inside the flutes for easy reference.

When buying a drill bit specifically for metal, first ensure that that bit is designed for metal and won’t heat up and snap when drilled through the material. Take the following additional factors into consideration before deciding which bit is best for your DIY project:

The point angle refers to the angle formed between the two cutting edges of the drill bit where they meet at the tip. Most drill bits for metal have point angles of either 118 or 135 degrees. Bits with a 118-degree point angle are best for softer metals, while 135-degree bits work best for harder metals. Some drill bit sets come with both 118-degree bits and 135-degree bits.

Carbide bits are made for drilling nonferrous metals (metals that do not contain iron) and do not work on ferrous metals. They typically cost more than HSS drill bits but are particularly wear resistant. Carbide bits are heat resistant, work at fast drilling speeds, and are more accurate than HSS bits.

A rubber-reinforced carrying case protects the drill bits from accidental drops and makes organization and transportation a snap. These drill bits work well on stainless steel and last a long time.

Carbide is one such material found in drill bits for stainless steel. Titanium and tungsten carbide are nearly as hard as diamond, making them ideal for penetrating steel. These carbide-infused drill bits are one strong option when drilling straight into stainless steel.

We liked the compact round carry case that these bits come in. The screw-on top held securely and seemed to be watertight after we accidentally dropped it in a puddle. However, the bit-size indexing was all but impossible to read. Although the large quantity of bits makes the set heavy, this would be a good choice for carrying to project sites where precision drilling is required.

Final Product Selection: We then began fine-tuning our list by replacing older models with the latest versions and eliminating any discontinued models. From there, we compared each model’s feature set to create a final short list, selecting the best-in-class options for various buyers, budgets, and scenarios.

The Drill America bits offered a similar drilling experience as our Best Overall pick because of their similar design features, but this set boasts improved durability thanks to a higher cobalt content. Both sets offered the same drill-bit size assortment, round shank, and 135-degree split-point construction. The Drill America bits remained noticeably sharper after an equal number of test holes, but they required three or four more passes on the grinder to sharpen.

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High-speed steel (HSS) drill bits are hardwearing and heat resistant. They are strong, durable, and safe to operate at high speeds. However, HSS bits must be sharpened over time, as they can dull quickly.

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As discussed in this review, ensuring you’re using the right drill bit when drilling metal is essential. Attempting to drill through metal without an HSS, cobalt, or carbide bit will cause it to snap and cause injuries. Additionally, you should consult a speed chart to ensure you’re not drilling too fast or too slow, which could shorten the life of the bit.

We certainly appreciated that the Irwin cobalt drill bit set had the best selection of bit sizes, in tight increments of 0.015625 inch from one size to the next. It would make a great choice for anyone who requires a high degree of precision in terms of hole sizes. However, in testing we saw that the straight shanks required a little extra care when chucking to ensure a secure fit without slipping. The straight shanks also made the bit a smidge more likely to get stuck if we applied too much pressure.

The added cobalt content makes these drill bits harder and more resistant to heat buildup than a typical HSS bit, giving them much greater durability. Also, unlike carbide tips or titanium coatings, cobalt drill bits can be resharpened when the tip becomes worn. These bits offer precision to users who drill stainless steel and other hard materials.

In testing, the Bosch M42 drill bits made drilling a pleasure thanks to their unique combination of design features. The M42 alloy itself allowed the bits to hold their sharp edge longer than others we tested, which meant more holes with less work stoppage to resharpen. The split-point design was easy to sharpen when needed and only required two or three additional passes on the grinder compared to M35 bits from other sets. The 3-flat shank was fast and easy to chuck securely, and we never had to worry about the bit slipping or becoming stuck in the work surface.

We found that customers who gave these drill bits a positive review liked that they were durable and made from high-quality materials. Others were impressed with the round case. On the other hand, customers with less positive things to say about these drill bits found that they dulled quicker than expected. Others said that the markings were difficult to understand.

Not all drill bits work on metal, and not all metal drill bits work on every type of metal. For example, if you’re operating on hardened steel, ensure the drill bit is strong enough to drill through that material. Some drill bits work best for aluminum, stainless steel, or rebar.

Expert Insights: To complement our in-house expertise, our team looked at reviews and videos from trusted publications and independent testers, spoke with subject matter experts, and drew insights from reader contributions.

With the above considerations in mind, we selected the following drill bits as our top picks for drilling stainless steel. Read on to find out the details on each set, how they performed in our drilling tests, and why we included them among the best drill bits for stainless steel.

Initial Research: Our research process began by generating a list of drill bits for metal with a significant number of verified buyer reviews and an average customer review rating of 4–5 stars. We looked at positive and negative reviews alike, focusing on information from both satisfied and critical buyers.

In our stainless steel drilling tests, these Milwaukee bits surprised us with noticeably faster, more precise penetration into the steel. The elevated pilot point, which is visibly shorter and narrower than others tested, seemed to offer the best balance of accurate placement and rapid material removal. We also noted that the center point did not get in the way of sharpening like some of the other pilot-point bits. Plus, Milwaukee’s hard plastic carry case was our favorite of the entire test group. It held the bits more securely, offered easy-to-read size indexing, and was easy to open and close securely. If the bit size assortment were more comprehensive, this set could have been our Best Overall pick.

We really liked the effectiveness of the pilot-point design. Instead of using a punch to mark the starting point and reduce bit travel, the pilot point allowed us to start drilling directly into the flat surface. However, due to its multitiered structure, we noted that the pilot point complicates the process of sharpening the bit. We worked through it slowly and with extra caution, we achieved satisfactory results.

These tips got into the material quickly and smoothly transitioned out to the full diameter of the bit. The edges held up remarkably well compared to M35 bits, but the tip design called for greater care when it finally came time to sharpen. We had to work slowly using extra caution to maintain the multitier tip profile.Though the thin plastic case is nothing to brag about, the size indexing was easy to read.

Those with lingering inquiries about drill bits for stainless steel may find the info they need in the answers to these frequently asked questions. It should help folks use and maintain the best drill bits for particular projects.

Though drill bits for stainless steel pull heavier duty, they are also made of more durable materials. Regularly maintained and properly stored, these kinds of drill bits may last a lifetime.

Not all drill bits achieve results in the same way. To identify the best drill bits for stainless steel, learning about characteristics like material, coating, frequency of use, and drill bit number are critical. Read on to learn the factors to consider as you search for the best drill bits for your projects that involve stainless steel.

While some bits come pre-lubricated, you should always double-check to ensure they have lubricant or cutting fluid before using it. Lubrication dissipates heat, reduces friction, and prolongs the life of the bit.

Cobalt drill bits are a good choice for ferrous metals. They have particularly high heat resistance and are harder than HSS bits. Cobalt bits are stronger than other bit types and can cut through even the toughest metals. However, they run at a high price point and are more brittle than other materials.

This set of M42 cobalt drill bits from Drill America includes 29 pieces from 0.0625 inch to 0.5 inch in 0.015625-inch increments. The bits are finished with gold oxide, which acts as a built-in lubricant to minimize heat, making this one of the best choices for a long working life when drilling tough metals. Each bit is made of high-grade M42 cobalt alloy steel and features a split point and straight shaft.

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Folks who want to be ready for tough steel drilling projects that might come up should consider these cobalt bits from Bosch. The kit includes 14 bits ranging in size from 0.0625 inch to 0.5 inch. They are made of M42 cobalt alloy steel, which is one of the best bit materials for drilling hard metals like stainless steel, cast iron, or titanium. The bits feature easy-to-sharpen split points and 3-flat shanks for easy, secure chucking into the drill. They also feature thicker threading than other twist bits, which helps them remove material more efficiently in less time.

Infusing drill bits with cobalt is another way that manufacturers achieve ultrahard drill bits. High-speed steel, also known as HSS, is the most common drill bit for metal drilling. Cobalt drill bits are an extension of HSS bits. They are made with a special steel alloy that includes 5 percent to 8 percent cobalt.

When figuring out what size drill bit to use, determine the hole size and the type of metal you are working with. From there, consult a drill bit sizing chart to match your hole size with the proper bit.

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This set was popular among reviewers for its durable design, clear markings, and ability to work on various metals. On the other hand, some customers felt these bits were duller than expected, while others were disappointed that these bits did not come in a plastic case.

Once we conclude our research, we craft a comprehensive, user-friendly article of recommended products and additional information to help our readers make the right purchase.

Before drilling, ensure the piece of metal you’re using is fully secure in a clamp. For the drill, use a center punch to create a small indentation where you want to drill, which will help the drill stay on target and prevent wandering.

Metal drill bits typically have rounded, no-spin, or hex shanks. When determining what shank design to get, look for one that fits your drill’s chuck size. No-spin bits have a fluted shank design and help keep the bit secure when drilling, while hex shanks have six sides that help keep the bit steady.

In our tests, we appreciated the Milwaukee step bits’ ability to drill precise holes without a center punch using a handheld drill. They tapped into the stainless steel quickly and worked smoothly. We also noted how easily they worked to enlarge existing holes—a task that’s nearly impossible to do well with regular twist drill bits. Sharpening the bits was surprisingly easy but required a completely different technique than twist bits. We used a diamond sharpening stone to flatten the smaller flute edge, and it only took about 5 minutes.

High-speed metal drilling creates excessive friction and heat. The extra stress placed on standard drill bits tends to wear them out quickly. Individuals who intend to drill stainless steel frequently should be sure to buy bits designed with longevity in mind.

Available in several grades, each with at least 10.5 percent chromium, stainless steel is popular because of its low maintenance, high sheen, and resistance to stains and rust. DIYers and trade professionals often need to drill stainless steel to complete a variety of electrical, plumbing, and automotive projects. Whether you’re expanding the size of a junction box punch-out or boring out a broken bolt, having the right drill bit matters. Drill bits built to work on softer material, like wood, won’t do the trick against stainless steel. Luckily, manufacturers design special drill bits capable of puncturing even the hardest grade of stainless steel.

Our team noted that customers who liked these bits were particularly impressed with their sharpness, which allowed them to slice through tough metals. Others also liked the high-quality, durable material, requiring minimal pressure on the drill. On the other hand, some customers found the packaging difficult to open, and others said the bits were overly fragile and broke easily.

With loads of available bits for hard metal applications, finding the right drill bits for stainless steel can be challenging. We spent more than 40 hours researching the best materials and designs used to make these bits, selecting our top picks, and then testing our picks in the workshop. Read on to find out what makes a durable and effective drill bit for stainless steel, our selection criteria, and how our selections performed in testing.

Because of its hardness, stainless steel is an unforgiving construction medium. Usually, there is only one chance to achieve the perfect drill hole. Another crucial consideration when purchasing drill bits for stainless steel is the drill bit number or size.

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We appreciated the affordability of this kit’s overall packaging and design, which allowed the tool quality to remain high while minimizing branding and engineering costs. The bits functioned comparably to similarly designed bits from bigger brand names, with good drilling capability and an easy-to-sharpen point. We also liked that the kit includes duplicates of several smaller sizes, as they are the ones that dull easiest and are more susceptible to breaking under excessive pressure. The case does feel a bit flimsy and the size selection is somewhat limited, so this won’t be a great fit for those who require high precision. But for occasional drilling, it’s a really good deal.

Over the course of 2 days, we spent about 12 hours shop testing the drill bits we selected. After unpacking and noting the physical characteristics of each bit set and the cases they came in, we started drilling. From each set, we tested four different bits, first in a drill press for precision and accuracy, then in a cordless drill to gauge comfort and smooth operation.

When you turn the drill on, make sure it is fully secure in your hand and apply consistent but gentle pressure. Excessive force could cause the bit to break or could cause overheating. A slow and steady feed will prevent the bit from binding or catching.

Many manufacturers complement construction materials like drill bits with metal coatings. These coatings promote penetration and protection of the drill bit. Black oxide coatings reduce friction and heat—a significant consideration when drilling metals. Black oxide also protects against corrosion and water, keeping the drill bits functional for a longer period.

Titanium carbonitride (TiCN) is likely the most durable metal coating available. TiCN bits are blue-gray. Their coating makes them incredibly resistant to wear and capable of enduring high-speed and high-frequency use.

Drilling holes in metal can be a challenge for the inexperienced DIYer. However, if you follow some basic tips and use the proper drill bits, you should get the hang of it quickly. Here are the top things to remember when drilling holes in metal.

Milwaukee Cobalt Red Helix drill bits make it easy to drill into hard stainless steel. This set includes 15 bits made of M35 cobalt alloy steel. They feature pilot points for fast, precise surface penetration without a center punch or pilot hole and 3-flat shanks to eliminate the hassle of bits spinning in the chuck. Bit sizes range from 0.0625 inch to 0.375 inch.

We spent several days researching drill bits for stainless steel and shopping around for the best options available online. Although solid carbide drill bits may be the professional machinist’s choice for drilling stainless steel, they are incredibly expensive. Other options like titanium-coated HSS are inexpensive but lack durability. We narrowed our search to cobalt drill bits because they can drill hard metals repeatedly without dulling right away, and they can be resharpened many times to extend their working life.

We found the 135-degree split tip to be very easy to sharpen. Also, the steel carry case proved durable and well organized with easy-to-read size indexing, although it weighed more than the heavy-duty plastic cases used by competitors. It’s probably best to keep this set in the shop and use a smaller set for traveling work.

If converting fractions of an inch to the metric system seems like no fun, this 19-piece drill bit set can help. Not only are these Stroton bits metrically sized in increments of 0.5 millimeters, from 1 millimeter to 10 millimeters, they also feature a unique three-stepped pilot-point design that penetrates stainless steel without traveling across the flat surface. The bits are constructed of tough M42 cobalt alloy steel for improved durability.

The 3-flat shanks of these bits eliminate slippage in the drill chuck. The combination of secure chucking, easy starting, and smooth operation make these bits an excellent choice for use in cordless drills at low speed for hard stainless steel or higher speed for mild steel. The kit includes Milwaukee’s #1, #4, and #9 step bits. The #1 drills from 0.125-inch to 0.5-inch holes in steps of 0.03125 inch. The #4 bit makes holes 0.1875 inch to 0.875 inch in 0.0625-inch steps. The #9 bit drills 0.875-inch to 1.125-inch holes in 0.0625-inch steps.

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Sharpening drill bits will help extend their lives and is particularly important when attempting to drill through hard metals. Use a bench grinder or drill bit sharpener to sharpen the cutting edges when they begin to dull.

Many metal drill bits come with coatings like titanium nitride (TiN) or black oxide. These coatings help reduce friction, increase heat resistance, and extend the life of the drill bit.

Drill bit numbers are related to wire gauge size. The larger the bit number, the smaller the diameter of the resulting hole. For example, a number 80 drill bit creates a hole with a diameter of 0.0135 inches. As the diameter grows larger, the bit number grows smaller. A number 1 drill bit, in comparison, has a diameter of 0.2280 inches.

This 29-piece professional-grade drill bit set from Irwin Tools covers an abundance of applications. The bit circumference spans 0.0625 inches to 0.5 inches by increments of 0.0156 inches. The bits themselves are heat- and abrasion-resistant, thanks to their industrial-grade high-speed steel cobalt-alloy construction. To aid penetration, these bits feature 135-degree split-tip points. Besides making these bits suitable for ultrahard materials like steel, the quality construction materials ensure longevity.

Following the guidelines on this revolutions per minute chart, we used each bit to drill four holes into 0.125-inch thick stainless steel, observing the ease of penetration, any bit travel across the steel surface, and the formation of metal chips/dust. We also noted how securely the bit was retained by the drill chuck and, when drilling by hand, how smoothly it transitioned from point penetration to the full diameter of the bit. Finally we used a bench grinder to sharpen the bits and drilled another hole with each one. Each of the sets we picked tested successfully, with the primary differences or improvements being edge retention, tip and shank design, and set configuration.

In addition to ultrahard materials and protective coatings, drill bit users who seek longevity should ensure the bit can be sharpened. While drill bits infused with carbide or cobalt keep their edge longer than a standard bit, investing in a set for life often means resharpening the dull drill bits over time.

To provide our readers with the best recommendations possible, we rely on several key sources of information to help guide our selection process.

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The DeWalt 14-piece Industrial Cobalt Alloy drill bit set is built for working on hard stainless steel, with features to prevent bit breakage, shank slippage, and travel on the work surface. The set includes 14 bits made of durable M35 cobalt alloy steel. It includes the most popular bit sizes from 0.0625 inch to 0.375 inch. Pilot points make it easy to start drilling precisely where the hole needs to be, while the 3-flat shank design prevents slipping in the drill chuck.

Titanium nitride (TiN) protects high-speed drill bits. Distinctive for their golden color, TiN-coated drill bits are ideal for high-speed drills. The coating provides the ancillary benefit of being ultradurable, making them an excellent value for consumers who intend high-frequency use.

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Customers who gave this product a positive review liked that it was durable and long lasting. They also complimented these bits’ excellent value and ability to work on stainless steel. However, we also noted some customers who said that these bits broke when they applied pressure, and others claimed that they seemed duller than other bits they had used.

While you don’t necessarily need to clean drill bits after every use, doing so will help keep them in the best possible condition. To clean a drill bit, wipe away excess residue and rub cutting fluid on it before putting it away.

For affordable drilling options, we chose these bits made of a proven material with a simple and functional design. The Comoware cobalt twist bit set includes 15 bits made of M35 cobalt alloy steel that dependably penetrate stainless steel. The bits feature an easy-to-sharpen split point and a straight shaft. They range in size from 0.0625 inch to 0.375 inch, including two each of the popular 0.0625-inch, 0.09375-inch, and 0.125-inch sizes, for a total of 12 different bit sizes. The kit comes in a lightweight plastic carry case with easy-to-read printed bit-size indexing.