What is Diamond Drill Bit? – All You Should Know!

Diamond drill bits are really important for drillings extremely hard and brittle materials such as glass, tile, stones, and many more. Diamond drill bits are a bit more expensive due to their wide usage and production cost. There are many things about the diamond drill bits. So let’s see what is diamond drill bit and how we use it?.

Diamond drill bits are two types according to their coatings. Those are Sintered and Electroplated drill bits. Diamond drill bits are used to drill extremely hard and brittle material. It can drill with more thrust and 350 RPM for the higher diameter tools and 5,000-7,000 rpm for the lower diameter drill bits.

The diamond drill bit is the hardest drill bit that we can use. There are drill bits and hollow bits also. Both are used for the toughest material. When you use diamond drill bits, you should know these things. So let’s keep reading to grab all in detail.

How Diamond Drill Bits Are Made?

Diamond drill bits are made with diamonds embedded into the metal. These drill bits produced 1.5 GPa pressure and 1250 °C. The real diamond powder is pressed onto the metal under this high pressure and temperature. These are two types.

These are sintered diamond drill bits, and electroplated drill bits are them.

Advantages of Diamond Drill Bits and Compered With other Drill Bits


  • Advantages+High grinding efficiency low grinding force
  • High wear resistance
  • Long life span, long dressing period
  • Low comprehensive cost

Diamond Drill Bits and Other Drill bits

Normally diamond drill bits are the hardest and tough masonry drill bits that can be used for drilling extremely hard material. So considering other drill bits, this is the most high performance and expensive than others.

Its price is really worth it for the usage. This is not able to use for metal, wood, plastic due to its clogging problem. There are options for that.

But you can drill tiles and glass using diamond drill bits successfully.

How to Select a Diamond Drill Bit?

Diamond is Coated on Steel in Two Ways.

Sintered diamond drill bits or burrs – The diamond has been bonded to the matrix at a very high temperature; therefore, several layers of diamonds are dressed on the steel. This will increase the durability and more resistance of the drill bit.

Electroplated or coated drill bits – Diomand is coated on the steel as a single layer. Then once the layer is wiped due to wear, you have to replace the tool. These are very economical and popular. Single Nickle is used as the bonded layer

  • Metal bonded diamond tools – Tool binding is a sintered metal containing diamond tool
  • Resin-bonded diamond tool – The tool bonding material is mainly resin powder
  • Plated Diamond tool – made by fixing the diamonds onto the tool’s base via electroplating method or via CVD (Chemical Vapor Deposition) method
  • Ceramic-bonded diamond tools – tools’ bonding material is usually glass and ceramic powder
  • Polycrystalline Diamond (PCD) – They are normally made by sintering many micro-size single diamond crystals at high temperature and high pressure
  • Polycrystalline Diamond Composite or Compacts (PDC) – made by combining some layers of polycrystalline diamonds (PCD)
  • High-temperature brazed diamond tools – made by brazing a single layer of diamonds onto the tool via a solder at a temperature of over 900 °C
Diamond core bits
Diamond drill bits and core bits

Read More About – What is Carbide Drill Bit?

Recommended Usage for Diamond Drill Bits

Normally diamond drill bits can be used in glass, concrete, stone, ceramic materials, and bones. They are frequently used on sea glass, beach glass, stone, precious gems, pebbles, ceramic tiles, glazed pottery, shells, antlers, and fossils.

In domestic, you can use it as a nail polishing and cutting tool.

You can drill marble blocks under loads up to 50 kN, at speeds of 355 rpm (slow speed), and at mechanical speeds up to 20 m/h feed rate. Due to high hardness and resistance, it can work under high temperatures and resistance.

For the small diameter drill bits, you can drill 5,000-7,000 rpm, and if the diameter is high, used the lowered RPM.

You can use water as the cutting fluid. It will remove the cutting dust quickly and clear the tool, which helps to increase the cutting process. Normally diamond drill bits are used to drill tough and brittle materials. Those are brake into small particles such as dust.

Do not use the damond drill bits for metal, wood plastic, or fiber. becuase these material will clog up the drill. You will have to clean the bit for every drillng step.

Do not drill the tempered glass or toughened glass with the diamond drill bits. It will crack the glass.

There is no burn mark on the tool. Suppose there is any you should reduce the drill bit RPM and feeding speed and thrust.

Available Diamond Drill Bits and Durability

Diamond drill bits are mainly available in two types by their structure. Diamond drill bits and core bits are them. Diamond core drill bits are available 1mm – 3mm and 3.5mm – 60mm and larger.

Mostly used drill bits are diamond core bits. These core bits are used for drilling or cutting inside the stone, concrete etc.

When considering these two bits, core drill bits stuck the debris inside, and drill bits are with limited diameters. These are the disadvantages of these two. You can remove the inner stuck debris with the cutting tool structure.

How Long Does a Diamond Drill Bit Last?

Normally, a diamond drill bit will last long according to the using lubricants, RPM, thrust, etc. The electroplated drill bit can drill 80-120 holes and sintered diamond drill bits can drill about 1200 holes and special technologies such as SMART CUT can drill about 2000 holes.

Do I need Pilot Hole for Diamond Drill Bits?

Normally pilot hole is not essential for the diamond drill bits. Because pilot holes are not able to make on the workpiece. You can use the tape on the workpiece and mark the location there. And then drill on it.

This mechanism will not be wandering the drill bit, and it will prevent unnecessary crackings.

Tom Mackency

Tom Mackency

Hi, I am Tom Mackency. It has been 10 years that I have been working as a professional woodworker since 2013. I am really enjoying my carrier by creating many kinds of projects in my workshop. But mostly I like for home improvement projects. Home improvement and DIY projects are the most interesting things for me. More than that, the coolest things are power tools. Those are very precious and efficient than a decade ago. So I try to introduce so many things about power tools, woodworking, DIY projects, home improvement and many more interesting topics here.