When you choose a drill bit for bricks or motor, what do you consider? What are the points that you consider this one is good for your task? As for me, I consider these 08 factors. I have listed out all of them by describing each in detail.
Normally, I use hammer drills as well as regular drills for drilling bricks and motors. It depends on the type of brick and location. As well as I use hammer drill bits as well as diamond drill bits when drilling bricks. All are considered according to the below facts.
The same masonry drill bit does not compatible with all types of bricks and drilling functions. So we have to change the drill bit according to the location and type of the brick wall. There are many facts you should consider before buying a drill bit for bricks. I have listed out all 08 facts that you should consider. So let’s keep reading on.
1. Drill Bit Geometry
- It has a slightly tight, corky shape.
- Looks like a large twist drill with a broad arrow-shaped head. Therefore, the tip of the drill bit is larger in diameter than the shaft.
- The cutting angle of most of the masonry bit tips is 135 degrees. Actually, it will vary on the manufacturer and the drilling material. The cutting angle can be between 118 and 135. Therefore, the ideal angle to hold the grinder for sharpening masonry bits is 60 degrees to 67.5 degrees, giving you an included angle of 120° to 135° without removing too.
- These bits can be resharpened with the help of a suitable and specific tool, thus maintaining efficiency of these bits.
- The flutes of a bit are sharp slots that grind up from the tip of the bit. The flute length of any drill bit is can identify from the leading edge of the cutting tip just to the end of where the flutes taper out.
2. Drilling Functions and Location
The environment in which this drilling is performed should be considered first. In places where silence is most important, such as a hospital complex, a hammer drill or SDS drill cannot be used, which causes more noise and vibration.
But the most efficient type of drill for drilling strong walls is the drill with hammering action. Those are hammer drills and SDS drill have hammer action. It will save time and energy.
Hammering action is required only in some cases while drilling bricks. Hammering action is not required for mortar so you can use a diamond drill bit easily.
3. Drill Bit Material
The most suitable material is tungsten carbide for the masonry drill bit. It helps in strong and efficient drilling. Tungsten carbide is a strong material. Therefore, it can carry the shock during hammer action and complete the work.
According to the Moh’s scale, the hardness of tungsten carbide is 9. That means it is second only to diamonds. Diamond is the material with the highest hardness in the environment.
Sometimes we have to use diamond drill bits. Those are really tough and no need hammering action. It is safe and free of notice and vibration. Hence you should have good knowledge about drill bit material, coating and usage.
4. Length of Drill Bit
While drilling, as mentioned earlier, the nature of the wall to be drilled should be considered while selecting the drilling tool. Things you must think about before drilling;
- A rough and accurate idea of the thickness of the wall should be taken.
- If there are network pipes or electrical cables inside the wall, they should be known about them.
- The nature of the wall should be observed. If it is made of tiles, drilling cannot be done with a hammering action.
Accordingly, the size of the drill should be decided. The drill bit with the appropriate length should be selected for that final decision.
Available length of masonry drill bits;
- 12 mm,
- 16mm,
- 24mm,
- 60cm and 1m
5. Surface Condition
According to the information received from the manufacturer for the drill bit, the appropriate drill bit should be used. That is, in most cases, the manufacturer provides surface recommendation details.
In some cases, when drilling a wall with two surface types, it is necessary to change the drill bit according to the situation. In all cases, efforts should be made to minimize the possible damage.
For example, if there is a tile layer, or wood layer next to a brick wall, in addition to the appropriate length drill bit, the type of drill bit should also be selected. As previously mentioned, although not efficient, drill bits other than tungsten carbide masonry drill bits can be used for mortar and brick drilling.
6. Lower RPM
Is it better to drill slowly? The answer is, of course, yes. Faster drilling requires a higher RPM (Revolutions Per Minute). Lower RPM is useful to prevent the overheating of the tip of the drill bit. In general, drilling is started slowly, and the pressure is gradually increased to get the job done efficiently. The suitable optimum drilling speed is 350 RPM to 750 RPM. If you are a newbie, read this drilling start guide.
By starting to drill slowly, you can drill without missing the right place to drill, and you can drill with attention to the hole to be drilled. Another thing to note is that although the hardness of tungsten carbide is high, the ability to break is quite high. So, the low speed ensures the safety of the user. It also reduces the cost of drill bits.
Therefore, the best course of action is as follows. Set the drill to low speed and rest one hand on the pistol grip and the other on the auxiliary handle. Check that the drill is level perpendicular to the wall. Because drilling at an angle causes problems and the holding power is much less.
Although if you require high RPM, choose a drill with a high voltage.
7. Brick Material
Identifying the type of brick is one of the most important factors when choosing a drill bit. Because we have to deal with different types of buildings with different brick materials. All bricks are not made with clay. Some are made with cement, stone etc. So we should know what is the inside brick in the wall.
Each brick’s strength can be varied with its material. So we should use a proper drill bit for this.
There are types of bricks we can observe
Types of bricks
- Clay bricks
- Sand lime bricks
- Concrete bricks
- Fly ash bricks
- Engineering bricks
| Brick type | Description |
| Clay | ➤ Traditionally, a brick is a small unit composed primarily of clay. ➤ The color is determined by the mineral content of the clay. ➤ Clay rich in iron oxide turns red if clay containing a lot of lime is white or yellow. |
| Sand lime bricks | ➤ Calcium silicate brick is also popular as sand lime brick. ➤ It contains about 88-92 % sand.8-12 % is mainly lime. ➤ Sand-lime bricks are formed when the constituent materials are bound together by a chemical reaction that occurs when wet bricks dry under heat and pressure. ➤ Sand lime bricks are more uniform in colour than other bricks. ➤ They require less mortar to be held together. |
| Concrete | ➤ Concrete bricks have a variety of shapes. (Square, triangles, octagons) ➤ Can be colored when processing. |
| Fly ash | ➤ It can be reused by using it in brick production. ➤ Consists of fly ash and cement. ➤ Concrete and clay are less heavy than bricks. ➤ Good heat and water resistance due to low absorbency. |
| Engineering | ➤ High compressive strength ➤ Low water absorption. ➤ It can be used to construction which needs strength and resistance to water and frost. |
You may not know some types of bricks as they are not popular in some countries. Also, the standard dimensions of bricks vary from country to country.
| Country | Brick type | Size (Length x Width x Height) |
| United States of America | Clay | 203 × 92 × 57 mm |
| United Kingdom | Clay | 215 × 102.5 × 65 mm |
8. Mortar Strength
Mortar is a mixture used in the construction industry to increase the bond strength between bricks. Which includes;
- Sand
- Cement or lime
- Water
After applying this mixture between the bricks, it hardens over time.
| Type of mortar | Description |
| Gypsum | ➤ A soft ancient mixture of gypsum and sand used in the Egyptian civilization. |
| Portland Cement | ➤ It became popular in the late 19th century as it allowed for faster construction due to its hard and quick setting. |
| ➤ An ancient type of mortar ➤ Non-hydraulic ➤ Sets very slowly through reaction with the carbon dioxide in air. It may be taken centuries. | |
| Modern | ➤ Nowadays, there are mortars with ingredients that must be contained in the correct proportions before the mortar can be properly made on the job site. ➤ The condition, color and strength of such mortars are high and the wastage in the production of this mortar is minimal. |
Its strength varies according to the type of mortar. Roughly it is between 5 MPa and -20 Mpa. The content of the mortar affects this a lot.
Conclusion
Regular masonry drill bits are not the common solution for all brick walls. It depends on the type of the brick, location, hammering action, and many more factors. So you should choose the most reliable drill bit for the bricks and motor. Sometimes you have to use a masonry drill bit, tile drill bit, or regular drill bit anytime. Remember the above 8 factors. You can buy the best one.
