Rotary hammer bits: what are there, how to choose and use?

A hammer drill is a more powerful and effective tool than a conventional drill. He will be able to perform all the same tasks, but also has additional capabilities. However, this goal can be achieved only with the correct selection of additional elements and accessories.

When choosing nozzles for a hammer drill, you must immediately clarify whether they are suitable only for this device or for a drill too. There are such types of similar elements:

• chisel;
• crown;
• construction drill;
• scapula;
• peak.

The main role among the nozzles is played by construction drills (used as widely as possible), they are designed for drilling holes in strong materials and structures. Most often, they are used to process concrete, natural stone and brick. The tail segment of the nozzle is invariably made as resistant to wear as possible.

An experienced builder is able to easily figure out, almost at a glance, what the properties of a particular drill are and for which rock drills it is suitable. The most popular shank format is SDS +. The diameter of such an element is 1 cm, its length is 4 cm. Thanks to 4 open grooves, it is first installed in the chuck, and then the torque is transmitted. Drills with a similar tail section are needed for household rock drills, although they can also be used in lightweight construction models.

The main part of the nozzle is made from specially selected alloys. The speed of work and the level of safety of the owner depend on their composition. The auger drill is designed for large holes with different diameters. Due to the significant torque, as well as due to the spiral structure, the following are provided:

• reducing the overall load;
• removing dust from the work area;
• saving time for builders.

If you need to prepare many relatively small holes, you need a drill with slightly sloped grooves. If the slope is steep, the attachment is optimized for high speed drilling. However, in this case, the rock drill is subjected to more stress than when using a screw auger. But you can safely drill a series of deep grooves. Drills with spiral grooves are chosen in cases where stability and a minimum level of vibration are in the first place.

The main part of the drill, which cuts materials, is a soldered tip made of strong alloys. The pace of work and the perfection of the holes obtained directly depend on how well it is made.

The classic type of soldering is performed with cross-shaped edges. Sometimes 2 or more cutting edges are prepared. This solution allows you to make the hole better.However, the labor intensity of the process is growing, and therefore the drill will cost more. Centering sharpening is considered a more modern solution, because it prevents the drilling part from moving to the side and helps to punch a better hole.

It is worth noting that some cutting edges are intentionally non-linear. The wavy design, in the middle of which there is a cleat and on the sides - cutting lugs, allows to reduce the overall load on the rock drill. Such a drill removes material in layers. As for self-sharpening bits, their ability to drill aggressively and forcefully is achieved through a specific sharpening angle. The drill will still wear out. However, the working edges will retain their performance longer than the main part.

With the help of a chisel, they beat off the old finish, and also punch holes for laying wires. The pike and blade are varieties of the hammer chisel. The need for the first device arises when you need to punch a hole in concrete or brick, remove layers of old building materials. The peaks are shaped like cones or pointed pyramids.

The blade is closer to the screwdriver, only its shape is curved. You can use this tool to remove old finishes or demolish asphalt. The flat chisel is very rarely used. It is even assumed that it will cease to be used in the next 10-20 years. The main disadvantage of this tool is that it takes a lot of effort to work.

Crowns for perforators deserve a separate discussion. Such nozzles are used when processing concrete and reinforced concrete surfaces. They are in demand in construction and electrical work. Thanks to the crown, you can drill a hole with a diameter of over 2.6 cm (which will not work with a drill).

For this purpose, a crown and other tips are usually used. Simple bits, even from Pobedit, are not effective enough, it is much more correct to buy a diamond one. You can, of course, stop the usual one from time to time, cool it with water, but this is very inconvenient. For a hammer drill to replace a wall chaser, it is not enough just to choose a good bit. It is necessary to use a drill of the appropriate level. The items supplied with the device are unlikely to fit. If the load is not too heavy, they will still be able to cope, but they will not be able to make a large strobe. For gouging, it is recommended to use crowns with a maximally twisted spiral.

Important: in apartment buildings, grooves in load-bearing walls and ceilings must not be cut. To avoid negative consequences and prosecution under the law, it is best to study the BTI plan before starting work. A construction vacuum cleaner is used to clean the air from the emitted dust. Strictly defined depth and width of the channels are observed. They should also be removed from door and window openings.

For mixing building mixtures, the perforator can only be used in conjunction with special attachments. The fact is that in pure form, these kneading machines are not suitable for mixing and quickly fail. If you need to mix more mortar, it is recommended to choose nozzles with a pair of spindles. But such a device is of interest mainly to professional teams. Those who want to make small repairs at home need to buy a fixture with one spindle, the practical difference is still hard to notice.

Most often, the mixing attachments are fixed with an M14 clamping nut. Such an element, judging by the reviews, fully fulfills its function.Some experts even believe that in the foreseeable future all manufacturers will switch to using such fasteners. SDS + is easy to install, but it is not very reliable and difficult to restore. The Morse taper is considered the most stable solution, but it is used only for expensive rock drills.

The overwhelming majority of mixing attachments for perforators have a length of up to 60 cm inclusive. Longer designs are impractical anyway; the benefits they get are not worth the extra effort. The recommended diameter of the rod is 12-16 cm. The spiral of the working part twisted to the right handles heavy mixtures better. If it is twisted to the left, then it is more correct to use the nozzle for light formulations that will not spray. With a reverse, this is not so important.

It is often necessary to use a puncher to remove paint previously applied to the walls. In this case, be sure to wear a respirator, thick rubber gloves and goggles. Requires attachments in the form of a special chain or grinding wheel. Ideally, this circle should be girded with wire. The chain is used when there are a lot of layers of paint, but a grinding wheel is preferable for cleaning concrete tiles. Another case when you need attachments for a hammer drill is preparing sockets for sockets and socket outlets. For this purpose, concrete processing crowns are used. Accurate selection of the size of the nozzle is critical, otherwise the job will be done in vain.

Using a hammer drill with attachments, you can also get rid of old ceramic tiles. The best accessory in this case is a concrete chisel. If the hammer drill weighs less than 5 kg, the chisel is mounted according to the SDS standard. With a mass of up to 12 kg, the SDS max mount is preferred, and when using even heavier devices, the hexagonal HEX mount is preferred. A lance-like nozzle can handle even hardened concrete, but the edges will be torn, so it is used only as a last resort, mostly unnecessary finishing is removed with a spatula.

For information on which equipment to choose for a hammer drill, see the next video.