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Drill Bit for Metal

(Last Updated On: 18 September 2023)

Metal drill bits

Adiseal Ultimate has been shown to be the best drill bit for metal in our test drilling into stainless steel with a drill press. It is the fastest and most durable metal drill bit available. In our test, it drilled more holes than any other metal cobalt drill bit.

As well as drilling more holes than any other product, it also drilled faster than any other bit tested. These included the best bits from the biggest brands in the world including Milwaukee, DeWalt, Bosch & Makita. Impressively Adiseal Ultimate drilled more holes than the best bits from the top 3 worlds brands combined.

best metal drill bit

Metal drill bit test

To test which is the best metal drill bit, we used a drill press to drill 10mm holes into 6mm thick stainless steel (SUS304). We used a Scheppach DP60 drill press. The rotation speed was set at 400 rpm for all of the bits tested. 10mm metal cobalt drill bits from the worlds biggest brands including Milwaukee Cobalt Red, DeWalt Extreme, Bosch cobalt and Makita were used to drill each hole. We also tested some non-cobalt drill bits including Milwaukee Thunderweb and Bosch PointTeq but did not include the results in the chart as it would not be fair to list non-cobalt bits with cobalt bits (Bosch PointTeq did not manage to drill any holes into the 6mm thick stainless steel SUS304).

For each hole, a 5Kg weight was hung on the drill press arm to ensure equal force was applied for each bit when drilling as well as equal rpm of the drill press. For durability testing purposes we drilled each hole without using any lubricant, coolant or cutting oil. Using lubricant, coolant or cutting oil can help reduce the temperature of the bits and help prolong the life of the bits.

Drilling of each hole was recorded and the time was measured after by looking at the time stamps on each video. From the test, Adiseal Ultimate was the best metal drill bit in terms of both the number of holes drilled and time it took to drill each hole.

Drill bit for metal test results chart

Best metal drill bit durability test results

10mm metal cobalt drill bitTotal number of holes drilled
Adiseal Ultimate cobalt135 holes
Milwaukee cobalt red75 holes
DeWalt Extreme cobalt39 holes
Bosch cobalt15 holes
Makita cobalt12 holes
Metal drill bit durability test results

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

Adiseal Ultimate 135 holes vs Top 3 competitor combined 129 holes.

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

By drilling faster & more holes than any other bit, Adiseal Ultimate metal drill bit saves money, time, tools & energy.


Saves money

Cheaper drill bits can end up costing more if they don’t last that long and can’t drill as many holes as more durable bits. Work out the cost per hole by taking the price of the drill bit then dividing it by the total number of holes drilled. The cost per hole on some cheaper drill bits might end up more than a more durable bit that drills more holes. In our test, the non-cobalt bit from Bosch PointTeQ drilled 0 holes whereas the bit from Adiseal Ultimate drilled 135 holes.

Example of cost per hole

To give you an example of the cost per hole saving lets look at the how much it would cost to drill 10 holes in 6mm stainless steel using Adiseal Ultimate drill bit compared to Bosch cobalt drill bit.

Adiseal Ultimate 10mm metal drill bit costs: £10.14
Cost per hole: £10.14 / 135 holes = £0.076666
Cost to drill 10 holes with Adiseal Ultimate drill bit for metal: £0.076666 x 10 = £0.77

Bosch cobalt metal drill bit costs: £8.31 (Average of 3 lowest prices found online on 12th Sept 2023)
Cost per hole: £8.31 / 15 holes = £0.554
Cost to drill 10 holes with Bosch cobalt metal drill bit: £0.554 x 10 = £5.54

Just comparing the cost per hole, Adiseal saves money.

Saves time

A drill bit that drills faster than other bits can save even more money on labour costs. As less time is taken to drill each hole, this can save even more money on top of the cost per hole saving mentioned above.

Example of saving money on labour cost

To give you an example of the saving on labour costs lets look at how much time and labour it would cost to drill 10 holes in the 6mm stainless steel using the Adiseal Ultimate drill bit compared to the Bosch cobalt.

If we say a construction contractor pays £20 per hour for a trades person to work, then per second that works out to: £20 / 3600 = £0.00555 per second.

Adiseal Ultimate would take 31.7 seconds x 10 = 317 seconds.
Labour cost to drill 10 holes with Adiseal Ultimate metal drill bit: £0.00555 x 317 = £1.76

Bosch cobalt would take 132.4 seconds x 10 = 1324 seconds.
Labour cost to drill 10 holes Bosch metal cobalt drill bit: £0.00555 x 1324 = £7.36

Adding these labour costs with the cost to drill 10 holes from before we get:
Adiseal Ultimate: £1.76 + £0.77 = £2.53
Bosch cobalt: £7.36 + £5.54 = £12.90

In reality, the savings are even higher when you take into account the savings on tools lasting longer and the money saved on lower energy use to drill each hole. A more durable drill bit can also save extra time, fuel and money as less trips to the wholesaler will be required to buy replacement bits.

Saves tools

Drilling faster also has the added advantage of making the tools last longer from lower usage. Bits that take longer to drill means the tools have to run longer and therefore potentially break earlier than tools that don’t have to run as long to drill each hole. Tools lasting longer can save extra money on top of the savings mentioned above.

Saves energy

Drilling faster than other bits means tools need to run for less time and therefore use less energy to drill each hole. Lower energy use means extra saving on money on top of the other savings mentioned above.

Lower energy use to drill each hole also makes Adiseal Ultimate the most environmentally friendly metal drill bit.

Other benefits

With Adiseal Ultimate drill bits, it is not necessary to drill a pilot hole. Due to the sharpness of the cutting edge, it avoids sliding and wandering. It also cuts larger pieces than other bits so there are less small chips to remove once drilling is complete. Another advantage of Adiseal Ultimate is the ability to drill cleaner cut holes than other bits.

Adiseal Ultimate Masonry & Multi Material Drill Bit

Also in the Adiseal Ultimate 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. It has numerous advantages over hammer drills.

How to use a metal drill bit

How to drill with a metal drill bit

  1. Prepare the Work Area

    Ensure you have a clear and well-lit workspace. Clear away any clutter or obstructions that could hinder your movement.

  2. 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.

  3. Secure the Workpiece

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

  4. Mark the Drilling Spot

    Use a center punch or awl to create a small indentation at the exact spot where you want to drill. This helps prevent the drill bit from wandering and ensures a precise starting point. With some bits like Adiseal Ultimate, this may not be necessary.

  5. Apply Masking Tape (Optional)

    If you’re concerned about scratches on the metal surface, you can apply masking tape over the drilling area. This can help protect the metal’s finish.

  6. Set the Drill Speed and Direction

    Set your drill’s speed to a level suitable for the metal you’re drilling. Lower speeds are often used for harder metals to prevent overheating. Overheating can reduce the life of the bit. Also, ensure the drill is set to rotate in the correct direction (clockwise for most drill bits).

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. Complete the Drilling

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

  13. Inspect the Hole

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

Be careful when touching the material you are drilling into or the drill bit straight after drilling as the temperature of these items might still be very hot. It is very easy to burn yourself with hot metal so allow them to cool if touching with bare hands or use suitable heat proof gloves.

Also be careful when toughing 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 is a drill bit for metal but it is also suitable at drilling many other materials including:

  • Stainless steel
  • Metal
  • Wood
  • Plastic
  • Fiberglass
  • Plus many other materials

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

Frequently asked questions about metal drill bits

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 are suitable. For harder metals like stainless steel and high-carbon steel, consider using Cobalt or Carbide bits.

Can I use a wood drill bit on metal?

It’s not recommended to use wood drill bits on metal, as they are not designed to withstand the hardness of metal. Metal drill bits are specially designed with sharper cutting edges and materials that can handle metal drilling.

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.

What is the peck drilling technique, and when should I use it?

Peck drilling involves drilling in short, intermittent bursts and withdrawing the drill bit to clear chips. It’s particularly useful for drilling deep holes in metal to prevent chip buildup and overheating.

How do I prevent overheating while drilling metal?

To prevent overheating, use a cutting fluid or lubricant to cool the drill bit and reduce friction. Drill at a slower speed, and if necessary, pause periodically to allow the drill bit to cool down.

Can I sharpen metal drill bits that have become dull?

HSS 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.

Can I use water as a coolant when drilling metal?

While water can act as a coolant, it’s not the best option for metal drilling. Cutting fluids or lubricants specifically designed for metal drilling provide better cooling and lubrication, reducing heat and prolonging drill bit life.

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.