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.
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.
Best metal drill bit durability test results
|10mm metal cobalt drill bit||Total number of holes drilled|
|Adiseal Ultimate cobalt||135 holes|
|Milwaukee cobalt red||75 holes|
|DeWalt Extreme cobalt||39 holes|
|Bosch cobalt||15 holes|
|Makita cobalt||12 holes|
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 bit||Average time to drill each hole for first 10 holes|
|Adiseal Ultimate cobalt||31.7 seconds|
|DeWalt Extreme cobalt||38.5 seconds|
|Milwaukee cobalt||55.8 seconds|
|Makita cobalt||69.9 seconds|
|Bosch cobalt||132.4 seconds|
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.
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.
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.
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.
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.
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
- Prepare the Work Area
Ensure you have a clear and well-lit workspace. Clear away any clutter or obstructions that could hinder your movement.
- 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.
- Secure the Workpiece
Clamp or secure the metal workpiece firmly to prevent it from moving during drilling. This ensures accurate and safe drilling.
- 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.
- 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.
- 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).
- 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.
- 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.
- 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.
- 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.
- 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.
- Complete the Drilling
Continue drilling until you’ve reached the desired depth. Slow down as you approach the end to prevent breakthrough damage.
- 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
- Plus many other materials
Where to buy drill bits for metal
Frequently asked questions about metal drill bits
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.