When you see a set of drill bits, how to pick the cobalt drill bit among them? Because most of the drill bits are the same in shape, color, and geometry. If you need to choose the cobalt drill bit, you should check its color and shape. If you need to make sure without any doubt, you can do some physical tests also. So let’s see, how to identify cobalt drill bits?
Cobalt drill bits can be identified by their dull golden color. It is not bright like titanium-coated drill bits. When you buy it, it is more expensive than other drill bits. You can also drill harder material and weld seams when you use it. Cobalt drill bits are brittle. Hence it will break easily when it falls on a harder surface. Cobalt drill bits are not corrosion. Hence it can identify in any wet environment easily.
01. Cobalt Drill Bits are Dull Gold in Color
You can quickly identify a cobalt drill bit by its unique color out of other drill bits. Cobalt drill bits come with a dull gold color which occurs in the baking process, and it is not a painting or a coating. This dull goldie color, also known as the amber surface finish, makes them distinctive even when mixed up with various drill bits.
02. Cobalt Drill Bits Can Drill Weld Seam.
Cobalt drill bits have a 68 – 70 HRC value of hardness. Hence it can be used to drill header material such as stainless steel, bronze, cast iron, titanium, and even weld seams you can drill using the cobalt drill bit.
03. Cobalt Drill Bits Are Expensive
When you buy a cobalt drill bit, you have to pay more for the cobalt drill bits. Due to their durability and performance, cobalt drill bits are expensive. Normally cobalt drill bits are 3 times longer.
04. Cobalt Drill Bits Are Brittle
If a cobalt drill bit falls into a harder surface, it can be brittle compared to the HSS drill bits. As well as, it does not withstand too much torsion or sideways pressure.
05. Cobalt Drill Bits Are Not Corrosion or Rust
Cobalt drill bits are not corrosion or rust even it used red hot. Hence you can identify the cobalt drill bit from other drill bits in any environment.
How to Identify Cobalt Coated Drill Bits?
Drill bits are coated with various materials in order to have excellent feeding rates and higher RPMs when working at higher temperatures. The coating will boost the lifespan of the tool and its productivity by a great deal.
Coated cobalt drill bits are performing well. You can identify cobalt-coated drill bits by their color.
The followings are the most used coatings on cobalt drill bits.
1. Cobalt TiN Drill Bits are Golden Color
Titanium Nitride (TiN) coating aids in delivering faster cutting speeds than uncoated tools. This is the most vastly used coating for cobalt drill bits. Titanium Nitride coated goldie cobalt drill bits benefit by extending tool life, lessening friction and thermal impact on the drill while facilitating incredible feeds.
2. Cobalt TiCN Drill Bits are Grey Color
Titanium – Carbonitride-coated (TiCN) drill bits usually have a sleek finish that can prevent chipping and wear, in addition to the primary advantages of a coating. Moreover, it prevents material from accumulating in the cutting area. Cobalt TiCN Drill Bits are ideal to use on aluminum materials. You can quickly identify this category as they get blue or grey colors.
3. Cobalt TiAlN Drill Bits are Violet Color
Titanium Aluminium Nitride (TiAlN) is a high-performance coating that works well in difficult-to-machine rigid materials such as cast iron, aluminum, etc. This coating dramatically improves the tool’s durability, resisting higher temperatures. This coating is ideal to use where heat resistance and additional toughness are needed on abrasive materials. TiAlN coatings majorly get a violet color.
Differences Between Cobalt And Titanium Drill Bits
Both drill bit types are extremely different in many ways. The following table showcases some of the prominent differences between Cobalt And Titanium Drill Bits.
| Titanium Drill Bits | Cobalt Drill Bits | |
| Material | Titanium nitride coating High-Speed Steel. | Alloy steel Up to 8% cobalt |
| Color | Bluish or bright gold color | Dull gold color |
| Heat Resistance | Moderate | High heat resistance |
| Wear Resistance | Very good | Excellent |
| Uses | Perfect to drill aluminum, copper, wood, cast iron, brass, mild steel, etc. | Perfect for drilling hard steel, welding seams, etc. |
What are M35 and M42 Cobalt Drill Bits?
When you are going to buy a cobalt drill bit, you can see there are two types of cobalt drill bits. These are M35 and M42 cobalt drill bits. I have prepared in depth guide about M35 and M42 Cobalt Drill Bits.
The M35 drill bit includes 5% of cobalt and M42 includes 8% of cobalt in the material mixture. Due to the different mixtures of cobalt, these bits have different physical properties. Hardness, wearing resistance, and heat resistance have increased due to these mixing proportions. So when you need to drill harder metals it is better to try with M42 cobalt drill bits every time.
Can You Sharpen A Cobalt Drill Bit?
Since cobalt drill bits are excellent heat resistance, they last longer than many other drill bits. But after using it for some time, the edges gradually get dull and require sharpening. Therefore, it is necessary to sharpen the cobalt drill bit.
Moreover, It is recommended to use a stronger drill bit sharpener for the sharpening process. You can get the work done with a grinding disc if you are skilled in this. It is necessary to have sharp drill bits for clean, convenient drilling.
Can You Sharpen A Coated Cobalt Drill Bit?
Yes, you can sharpen coated cobalt drill bits, but this will damage and break away the applied coating shortening its durability. Titanium-coated drill bits do not require regular sharpening.
The titanium coating builds a more rigid surface on the drill bit, protecting its edge for an extended period. The coating gets worn off after using it for some time. So consider sharpening the drill bits once the coating is gone. If the coasting gets removed, the drill bit loses much of its heat friction.
