LAST UPDATED: September 12, 2019
Best Cobalt Drill Bits: Drill Through Tough Materials
Use any of these high-quality, cobalt construction drill bits to work through any hard surface
The Review Team
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PUBLISHED ON September 12, 2019
Drill bits are typically used with handheld drill guns, lathes, and machining centers and are used to make holes in tough or semi-tough material. Most cobalt drill bits are made from a combination of cobalt and steel; cobalt alone is a weak drilling material that may deteriorate. Read our buying guide for some of the best cobalt drill bits on the market today.
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Benefits of Cobalt Drill Bits
- Drill through hard materials. Cobalt drill bits are reinforced with steel to create a high-performance structure that can bore through hard materials like stainless steel and titanium. Most of the tools have cobalt M35- and M42-grade constructions that enhance the unit’s durability and heat resistance when boring through hard surfaces.
- Versatile application. Most cobalt drill sets can be installed on almost all power tools. They come with bits of different sizes that sit firmly in the power tool without spinning or twisting under intense drilling jobs. They can also be used to drill through all kinds of surfaces, including plastic, wood, most metals, and even rough surfaces.
- Enjoy DIY projects. Cobalt drill bits are safe and handy tools for every DIY enthusiast who require a portable drill bit set with a lot of precision. Cobalt drills are protected from wear and include markings that help you identify what size is best to work with. They are the best tools for household applications as they are more durable than standard bits and can fit in a standard drill gun.
Types of Cobalt Drill Bits
Twist drill bits are a widely-used option due to their versatility. They can drill through all types of materials and come in different sizes for different applications. They are typically coated with a metal oxide to increase their heat resistance capabilities. You won't have to worry about the spinning, twisting, or breaking, and they can be fitted into a wide range of power tools. The shorter the length of the twist drill bit, the more sturdy it is.
Countersink drill bits are typically used on wooden surfaces. They feature a tapered fastener head for stability when the drill bit is installed on a power tool. They drill without twisting or spinning. However, the drill can’t bore into the surface without a pilot hole and a small middle hole.
These drill bits have a flat bottom with a tiny hole in the middle that effectively cuts into almost all surfaces. Counterbores are best for wood and plastic surfaces. They may break if used to drill through metals. Moreover, counterbore drill bits are made of cobalt steel that’s not coated with anything for high-speed drilling.
Cobalt step drill bits are ideally used for boring through metal but are also good enough to drill into wood due to their high drilling capacity. A single step drill bit can drill holes of different diameter sizes due to the step design of the tool. It can also drill a hole as deep as 0.25 inches through metal.
Drill America was founded in 1927 and is an international designer and distributor of cutting tools. From its headquarters in Miami, Florida, the company makes some of the best drill bits, countersinks, counterbores, end mills, and reamers among other products. One of its best-selling drill bits that have an M35 quality cobalt steel structure is the Drill America Cobalt Drill Bit Set.
DEWALT is a multinational manufacturer of power tools and hand tools. The company was founded in 1924 and is currently a subsidiary of Stanley Black & Decker Inc. DEWALT is headquartered in Baltimore, Maryland, and designs some of the best cordless power drills, saws, axes, hammers, breakaway blades, and drill bits. One of its top-rated cobalt drill bits is the DEWALT Cobalt Drill Bit Set.
Craftsman is a subsidiary company of Stanley Black & Decker Inc. that was introduced into the power tool industry in 1927. All of its products are made in the United States, and it specializes in the design of outdoor tools, hand tools, storage tools, and power tools. Craftsman products are innovative and help you organize your workspace. One of Craftsman’s drill bits that are worth giving a shot is the Craftsman Cobalt Drill Bit Set.
Bosch is a German multinational technology company that was started in 1886 by Robert Bosch. The company makes household appliances, power tools, and automotive accessories. It also has a few subsidiary engineering companies under its umbrella, including Bosch Rexroth, ETAS, and Dremel. Consider trying out the Bosch Cobalt Metal Drill Bit, which is good for drilling into abrasive metal like cast iron.
Cobalt Drill Bits Pricing
- Under $50: Budget this much for an affordable but sturdy cobalt drill bit that can drill through almost all metal surfaces. Most of the tools are cobalt M35-grade drill bits and typically come in a set of fewer than 20 pieces. However, most of the units here are not built for durability.
- Over $50: Expect to spend around this much for a cobalt M42-grade drill bits that offer a long service life. The more expensive units can come in a set of up to 50 pieces, and they are packaged in well-thought-out plastic cases with index markings for the sizes. They also have a carrying handle and a lock for safekeeping.
Long drill bits are typically less durable than shorter ones. The length reduces the unit's toughness and resistance to breaking. Shorter drill bits are more resistant to spinning, twisting, and breaking. This is due to the sturdiness of a shorter structure combined with more twists in the drill bit that make a thicker and firmer structure.
The percentage of cobalt in the structure should be high for better performance. A higher value of cobalt increases the unit’s resistance to heat and makes a sturdier structure. For example, M42-grade cobalt steel contains eight percent of cobalt, while a cobalt M35 grade only contains five percent of cobalt.
- Construction: Steel is the best metal to mix with cobalt as it increases the bit’s strength and ability to cut through stainless steel, cast iron, and other tough metals. The drill bit should be coated with a metal-oxide for enhanced corrosion and wear resistance.
- Design: The design of the drill bit mostly applies to the tip point. The most common design is a split-point, which is better at drilling through thick metal. Other designs are tapered-point, V-point, fish-point, and brad-point. Go for a design that suits the type of work you intend to do.
Best Cobalt Drill Bits Reviews & Recommendations 2020
What you will first notice about the Drill America Cobalt Drill Bit Set is an aesthetically-appealing black and gold container that you can hang on your belt for easy access. The round container has 29 drill bits arranged in a circular pattern according to size, in 1/16-inch to ½-inch by 1/64-inch increments. The drill bits are engineered from M2 premium high-speed steel that can bore into almost all hard metals, including stainless steel, aluminum, iron, and titanium.
The drill bits have a gold-oxide finish that enhances the metal’s resistance to wear, scratches, and heat. It further lubricates the finish to facilitate fast-speed drilling. It also features a 135-degree split-point tip that seamlessly penetrates tough material without a pilot hole. The bits can be used in a wide range of machines without the risk of bending, twisting, or breaking.
One drawback of this drill bit set is that the drill takes too long and a lot of effort to drill through stainless steel. Also, the drill bits may become blunt in the process. The set also comes in a fragile plastic container that may arrive damaged upon delivery and may easily break if dropped. Moreover, it’s a bit challenging to read the drill sizes from a cylindrical container.
The DEWALT Cobalt Drill Bit Set is made from an alloy of industrial-grade cobalt and stainless steel for enhanced durability. The bits can easily drill into wood and metals, and they feature a 135-degree split-point tip that provides a good grip for spinning and twisting the drill. The unit also features a pilot-point that minimizes lock-up or clogging when breaking through any material. It, therefore, makes accurate and clean holes.
These DEWALT drill bits are designed to offer great performance along with maximum speed. They will last longer if you use a lubricant when drilling into metal and employ a straight drilling technique. The sizes range from 1/16 to 3/8 inches, and a sliding rubber lock prevents the drill bits from falling off before unboxing the unit.
A major drawback of this model is that the drill bits heat up quickly after drilling a few holes even when used with a lubricant. Additionally, you may notice that the drill bits become dull after cutting through hard metal like stainless steel. You may also have to find an alternate storage unit for the tools after removing the packaging.
The Craftsman Cobalt Drill Bit Set is an indexed drill bit set made from a combination of solid cobalt and steel. The bits have a durable structure that’s suitable for heavy-duty use and drilling through rough surfaces. The bits are also gold-coated to increase their resistance to rust, wear, and scratches. The drill bits are housed in a high-quality plastic case with index markings for the sizes, which range from 1/16 to 3/8 inches.
These drill bits have a high-drilling capacity and can drill through thick metals like stainless steel. A unique feature of this set is that the bits have a split-point that drills upon contact on any surface. You don’t have to make a pilot hole for accuracy, which is convenient when performing repetitive drilling jobs. Moreover, the bits can be used with a hand drill or a drill press.
However, this set is not made of pure cobalt, and the drill bits may snap under intense pressure. The drill bit tip may snap off easily, especially when drilling hard metal like stainless steel. That’s enough to ruin the entire tool. Also, the end of the drill bit isn’t reinforced with a side notch, and for that reason, it may feel unstable when drilling through rough or tough surfaces.
- Even though cobalt drill bits are designed to bore through wood, plastics, and other softer material, we recommend that you don’t use it solely for that purpose. The strength produced by cobalt drill bits could be overkill when used on a soft material, and you may damage the drill bit if you only use it for such projects.
- You don’t always have to buy a replacement kit every time your drill bits become blunt. Simply sharpen each tool on a bench grinder or a belt sander. You could buy an industrial sharpener for large-scale applications. Do not wear gloves or put your hands too close to the sharpening unit as they may be caught up in the sharpening device.
- A cobalt drill bit is a very powerful tool, and things can go wrong when using it. The tip may snap, sparks could form, and a lot more could happen. You should, therefore, remember to wear protective gear when drilling. This includes goggles, gloves, and safety shoes.
Q: Are cobalt drill bits better than carbide drill bits?
A: Neither is better since they are used for different applications. Cobalt drill bits are an upgraded form of high-speed steel with five to eight percent of cobalt infused into the material. They are, therefore, a great option for drilling into hard metals and can be used in hand drills and drill presses. On the other hand, carbide drill bits are harder than the cobalt alternatives and are only designed to handle large-scale production drilling. They can bore through the hardest metals.
Q: Which is the best drill point angle for a drill bit?
A: 118 degrees is the standard drill point angle for almost all types of drill bits. That is the distance from the tip of the drill bit to the parallel plane where its projected on. However, most high-end cobalt drill bits maintain a 135-degree angle for enhanced speed when drilling through hard metals.
Q: Do I need to lubricate my cobalt drill bit every time I use it?
A: You should always use cutting oil or a high-quality lubricant when drilling metals. It will help reduce friction for faster and smoother drilling, and it prolongs the life of the drill bit. It also prevents heat buildup and sparks, which often happens with metal-to-metal contact. You don’t need to use a lubricant when drilling through wood or plastic
If you want a cobalt drill bit set that comes in a convenient carrying container with a size index, resists heat buildup, and includes a lifetime warranty, then consider our top pick, the Drill America Cobalt Drill Bit Set.
However, if you want a simple and affordable cobalt drill set for your DIY projects, then consider the DEWALT Cobalt Drill Bit Set.