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Drill Bit for Metal

Best Metal Drill Bits 2024: Fastest & Most Durable

Adiseal Ultimate cobalt metal drill bit has been shown to be the best metal drill bit available. It has been shown to be the most durable and fastest drill bit for metal available in numerous tests. In our test drilling into hardened stainless steel, it drilled more holes than all other metal drill bits. In terms of durability and drilling speed, Adiseal Ultimate has been shown in tests to be better than the best drill bits from big brands like Dewalt, Bosch, Milwaukee and Bosch.

Best drill bit for metal test results chart.

What is the best metal drill bit?

To find out what is the best metal drill bit, we carried out endurance and drilling speed tests using a drill press with a weight hung on an arm of the drill press. Impressively, Adiseal Ultimate drilled more holes than the best bits from the top 3 worlds biggest brands combined. (Milwaukee cobalt red) 75 + (DeWalt Extreme cobalt) 39 + (Bosch cobalt) 15 = 129 holes, whereas Adiseal Ultimate drilled 135 holes on its own.

Adiseal Ultimate drilled 9 times the number of holes than the best cobalt bit from Bosch & over 3 times the number of holes than the best cobalt bit from DeWalt.

Best metal drill bit durability test results

10mm metal cobalt drill bitTotal number of holes drilled (in 6mm thick stainless steel, SUS304)
Adiseal Ultimate cobalt135 holes
Milwaukee cobalt red75 holes
DeWalt Extreme cobalt39 holes
Bosch cobalt15 holes
Makita cobalt12 holes
Cobalt drill bit durability test results

Best metal drill bit speed test results

As well as drilling more holes than any other metal drill bit, Adiseal Ultimate also drills faster than any other bit. In the same test as above, we also measured the time it took to drill each hole. We did this for the first 10 holes and recorded the average.

10mm metal cobalt drill bitAverage time to drill each hole (in 6mm stainless steel) for first 10 holes
Adiseal Ultimate cobalt31.7 seconds
DeWalt Extreme cobalt38.5 seconds
Milwaukee cobalt55.8 seconds
Makita cobalt69.9 seconds
Bosch cobalt132.4 seconds
Metal drill bit speed test results

Adiseal Ultimate was over 4 times faster the best cobalt bit from Bosch.

Please note, these are our test results from internal testing. We recorded a video of each hole being drilled. These videos are available on request for your test accuracy verification purposes.

Best cobalt drill bit for metal.

Metal drill bit test

We conducted tests to find the best metal drill bit by using a Scheppach DP60 drill press. The test was to drill as many 10mm holes as possible in 6mm thick stainless steel (SUS304) with each drill bit being tested. The drill press maintained a consistent 400 rpm speed for all tested bits. We used the best 10mm metal cobalt drill bits from reputable brands like Milwaukee Cobalt Red, DeWalt Extreme, Bosch Cobalt, and Makita. To ensure consistency, a 5kg weight was suspended on the drill press arm during each hole’s drilling, maintaining uniform force and RPM. Notably, we conducted durability tests without lubricants, coolants, or cutting oils, although these can help reduce the bit’s temperature and extend its lifespan. The drilling processes were recorded and timed via video timestamps. Following the tests, the Adiseal Ultimate metal drill bit proved to be the best metal drill bit available, excelling in both being the most durable and fastest drill bit for metal to drill each hole.

Drill bit for metal test results chart

It’s important to note that some non-cobalt drill bits like HSS bits (high speed steel), including Milwaukee Thunderweb and Bosch PointTeq, were also tested but not included in the chart to maintain fairness (Bosch PointTeq was unable to drill any holes at all in the 6mm thick stainless steel SUS304).


By drilling faster and drilling more holes than any other bit, Adiseal Ultimate cobalt drill bit:

Saves money

Cheap drill bits may cost more over time if they wear out quickly and drill fewer holes than durable ones. Calculate the cost per hole by dividing the bit’s price by the total holes drilled. Cheaper bits might have a higher cost per hole than more durable ones. In our test, Bosch PointTeQ’s non-cobalt bit failed to drill any holes, while the Adiseal Ultimate metal drill bit successfully drilled 135 holes in total.

Example of cost per hole

To compare costs, let’s consider drilling 10 holes in 6mm stainless steel with the Adiseal Ultimate and Bosch cobalt drill bits.

Adiseal Ultimate 10mm metal drill bit price: £10.14
Cost per hole (£10.14 / 135 holes): £0.076666
Cost to drill 10 holes: £0.77

Bosch cobalt metal drill bit price: £8.31
Cost per hole (£8.31 / 15 holes): £0.554
Cost to drill 10 holes: £5.54

Based on cost per hole, Adiseal is more cost-effective. Further savings can be observed as detailed below.

Saves time

A faster-drilling drill bit not only saves on the cost per hole but also reduces labour costs. This is because less time is required to drill each hole, resulting in additional cost savings.

Example of saving money on labour cost

To highlight potential labour cost savings, consider the time and effort required to drill 10 holes in 6mm stainless steel using the Adiseal Ultimate and Bosch cobalt bits.

Assuming a construction contractor pays £20 per hour for a tradesperson’s work, it amounts to £0.00555 per second.

Adiseal Ultimate: 317 seconds to drill 10 holes.
Labour cost: £1.76

Bosch cobalt: 1324 seconds to drill 10 holes.
Labour cost: £7.36

Adding these labour costs to the drilling costs above, total cost to drill 10 holes is:
Adiseal Ultimate: £2.53
Bosch cobalt: £12.90

In reality, additional savings come from prolonged tool lifespan, reduced energy consumption per hole, and fewer trips to buy replacement bits.

Saves tools

Faster drilling extends tool lifespan by reducing usage. Slow-drilling bits increase runtime, potentially causing quicker wear. Longer-lasting tools can offer additional cost savings.

Saves energy

Faster drilling reduces tool runtime, saving energy and additional money on top of other mentioned savings. Lower energy use to drill each hole also makes Adiseal Ultimate the most environmentally friendly metal drill bit.

Other benefits

Adiseal Ultimate cobalt drill bits don’t require pilot holes thanks to their sharp cutting edge, preventing sliding and wandering. They also produce larger removed metal pieces, reducing the need to clear numerous small chips after drilling. It can also drill cleaner cut holes compared to other bits.

How to use a metal drill bit

How to drill with a metal drill bit

  1. Wear Safety Gear

    Put on safety goggles to protect your eyes from metal shavings, and wear ear protection if the noise level is high. Work gloves can also provide additional protection.

  2. Secure the Workpiece

    Clamp or secure the metal workpiece firmly to prevent it from moving during drilling. This ensures accurate and safe drilling.

  3. Mark the Drilling Spot

    Use a center punch or awl to make a small indentation at your desired drilling point. This prevents the drill bit from wandering and ensures a precise start. However, with some bits like Adiseal Ultimate, this step may be unnecessary.

  4. Set the Drill Speed and Direction

    Adjust your drill speed to match the metal you’re drilling; slower speeds work well for harder metals to prevent overheating and extend the bit’s life. Ensure the drill rotates in the correct direction, usually clockwise for most drill bits.

  5. Apply Lubrication

    Apply a suitable cutting fluid, coolant or lubricant to the drilling area. This helps reduce friction, heat, and prolongs the life of the drill bit.

  6. Start Drilling

    Hold the drill perpendicular to the metal surface. Place the drill bit’s tip into the center punch indentation and apply gentle pressure. Start drilling slowly to create a pilot hole.

  7. Maintain Steady Pressure

    As you continue drilling, maintain a steady, even pressure on the drill. Avoid pushing too hard, as the drill bit’s cutting edges should do the work.

  8. Peck Drilling Technique

    For deeper holes, use the peck drilling technique. Drill a short distance, then pull the bit back to clear the chips. This prevents clogging and heat buildup.

  9. Cooling and Lubrication

    If you notice the drill bit heating up, pause occasionally to apply more cutting fluid or lubricant. This helps keep the drill bit cool and prevents it from dulling prematurely.

  10. Complete the Drilling

    Continue drilling until you’ve reached the desired depth. Slow down as you approach the end to prevent breakthrough damage.

  11. Inspect the Hole

    Examine the drilled hole for smoothness and accuracy. If needed, you can use a deburring tool to remove any rough edges.

Exercise caution when handling the drilled material or the drill bit immediately afterward, as they can still be very hot. Hot metal can cause burns, so either allow them to cool before touching with bare hands or use appropriate heat-proof gloves.

Also be careful when touching the removed chips as they can be very sharp and can cut easily. It is advisable to wear gloves if you need to handle them.


What materials can Adiseal Ultimate metal drill bit drill into?

Adiseal Ultimate cobalt metal drill bit is suitable at drilling many other materials including:

  • Stainless steel
  • Hardened steel
  • Metal
  • Aluminum
  • Bronze
  • Brass
  • Copper
  • Cast iron
  • Plain carbon steel
  • Wood
  • Plastic
  • Fiberglass
  • Plus many other materials

What sizes are Adiseal Ultimate cobalt metal drill bits available in?

Adiseal Ultimate cobalt metal drill it is currently available in the following sizes:

Where to buy drill bits for metal

In the UK to buy drill bit for metal, please contact us for details of your local stockist. For other countries, please visit www.guglue.com

Adiseal Ultimate Masonry & Multi Material Drill Bit

In their attempt to make available the best drill bits, also added to the Adiseal Ultimate drill bits range is the fastest no hammer masonry drill bit & multi material drill bit. It can drill faster than any other drill bit when drilling without hammer function on the drill. This gives it numerous advantages over hammer drills. It will drill into brick, drill concrete, wood and many other building materials. This carbide bit has been shown to be the best masonry drill bit with a hex shank.

Frequently asked questions about metal drill bits

What is the best drill bit for drilling metal?

Adiseal Ultimate has been shown to be the fastest and most durable metal drill bit in a test drilling into stainless steel. It drilled faster and drilled drilled more holes than any other cobalt drill bit.

What are the main types of drill bits used for drilling metal?

The main types of drill bits for metal are High-Speed Steel (HSS) drill bits, Cobalt drill bits, Carbide drill bits, and Diamond-Coated drill bits.

How do I choose the right drill bit for a specific type of metal?

Choose a drill bit based on the hardness of the metal. For softer metals like aluminum, brass, and copper, HSS bits (high speed steel) are suitable. For harder metals like stainless steel and high-carbon steel, consider using Cobalt or Carbide bits.

What is the purpose of different point angles in metal drill bits?

Point angles affect the drilling efficiency and the type of metal they’re best suited for. Common point angles are 118 degrees for general-purpose drilling and 135 degrees for harder materials. Smaller point angles like 90 degrees are suitable for countersinking.

Can I sharpen metal drill bits that have become dull?

HSS (high speed steel) and Cobalt drill bits can be sharpened using a drill bit sharpener or bench grinder. Carbide and diamond-coated drill bits are more challenging to sharpen and may require professional service.

Can I use a cordless drill for metal drilling?

Yes, cordless drills can be used for metal drilling. Choose a drill with adjustable speed settings and sufficient power to handle the metal you’re drilling. Make sure the battery is fully charged for consistent performance.

Can I use the same drill bits for different types of metal?

While some general-purpose drill bits can work for multiple types of metal, it’s best to choose a drill bit specifically designed for the hardness of the metal you’re drilling to achieve optimal results.

Suhail Matadar has extensive experience in the construction industry as an electrician, involved in installing, inspecting, and testing electrical systems in various projects. He excelled in sales, working for a major UK wholesaler, selling construction products to professionals and the DIY market. Suhail's background includes working at a leading home emergency repair company dealing with trades people. With a BEng (Hons) degree in Electronic Engineering, Suhail has worked with PLCs in the nuclear fuel manufacturing industry. During his studies, he gained practical experience at a chemical manufacturing company known for producing award-winning cleaning, hygiene, and livestock protection products for over a century. Currently, Suhail runs a global business specialising in supplying, researching, testing, and distributing chemical construction products like adhesives and sealants.