How to choose a hammer drill for personal use? Nowadays, buying a branded drilling tool is not a problem, but how to choose the right hammer drill for yourself and your tasks? Explore the punch device and specifications.
Energy and frequency of impacts
For a hammer drill, the impact function, measured in joules, is very important. The performance of the device, as well as the diameter of the hole to be machined, depends on the impact energy. For daily work with a hammer drill, this is one of the most important indicators.
It is essential that the hammer drill at the maximum will very quickly deplete its resource, and with the hammer drill they perform this work for a long time without wear, especially with the single-mode model.
It turns out that energy and frequency determine the level of performance. When choosing a perforator on your own, you need to evaluate the amount of work on chiselling, then, according to the specified characteristics of the impact frequency, calculate the approximate productivity.
How to choose a hammer drill for personal use?
Choosing the right drilling tool means making home repairs easier for a long time. How can you successfully choose a puncher in order not to overpay for the brand and get high-quality equipment?
Several decades ago, only powerful electric drills equipped with drills for metal and concrete were used in everyday life. A truly branded, specialized tool was sold only abroad; it was impossible to just go to a construction supermarket and choose a suitable device.
What is the difference between a drill and a hammer drill and vice versa
The hammer drill is characterized by a longitudinal axial movement of the working part, similar to an impact drill. Therefore, hammer drills are confused with a heavy drill. In words, there is practically no difference, however, the hammer drill functions on the basis of pneumatics, and any impact (heavy) drill works thanks to mechanics.
Hence the difference in surface speed. Pneumatic drilling of holes in concrete, brick and stone walls reduces physical stress on the user. For any hammer drill, similar work is associated with great fatigue, and the hammer drilling mode wears out the internal components of the drill very quickly.
We come to the conclusion that the hammer drill should be larger and more massive than a drill with an impact function.
How to repair a hammer drill with your own hands: disassembly, assembly,
Any tool, including a hammer drill, requires special care and careful use. Therefore, each owner of such an electric tool is obliged to regularly inspect the unit, to know how to disassemble a hammer drill. It is quite possible to disassemble and repair the device at home without spending a penny on the services of a specialist.
A hammer drill is an indispensable tool at any construction site, but due to careless use it wears out very quickly and fails. This is due to the high stress on the tool. As we know, the rock drill is often used at full power in the most difficult conditions. Due to such loads, even branded models are susceptible to breakdowns. Therefore, every owner of this device should know how to repair a punch with his own hands.
Like any other technical device, a hammer drill can be repaired, for this it does not have to be carried to a specialized workshop. Although not every man knows how to repair a hammer drill, it doesn’t matter! This article will help you do your DIY repairs without assistance.
Is DIY repair realistic?
Not always a visual inspection will help to identify the cause of the breakdown. In this case, the next step is to disassemble the punch. If the device has served for many years and is not of significant value, you can try to find the cause of the breakdown by disassembling the tool into separate parts. Feel free to start an offline repair if the cause of the tool malfunction is visible visually and you already have an idea of the perforator stuffing. If the device was purchased relatively recently, and the model itself is more modern and costs a lot of money, then it is best to contact a service center, because an independent repair can not only fix the device, but cause harm. If the inspection of the unit did not reveal a breakdown, then it is necessary to postpone the repair of the hammer drill. In the latter case, it will not be superfluous to consult an experienced specialist.
Disassembly and assembly of the tool
A damaged wire on the device, like other minor mechanical damage, can be easily noticed. If you make a thorough inspection of the parts of the instrument, then it is not difficult to see other minor malfunctions that led to the breakdown of the device. For more serious problems, you need to disassemble the hammer drill. And upon completion of the repair work, also the assembly of the perforator. The second operation in some cases is more difficult than the first appearance after assembly of unnecessary parts will indicate repair miscalculations. To prevent this from happening, you need not only to know how to properly repair a hammer drill, but also how to assemble it. It is important to be careful and careful when repairing a tool, then in 99% of cases the repair will be successful!
To start repairing a perforator, including a barrel type, you must properly disassemble the device:
- Removing the rubber tip and ring spring. After that, we proceed to remove the drill sleeve casing itself.
- We carefully take out the steel ball, which acts as a fixation.
- Removing the switch handle, having previously placed the operating mode lever to the maximum position. Press the button to fix the position.
- Removing the cover (back) on the handle.
- Removing the motor brush.
- Removing the front part, for which you need to unscrew the 4 screws located near the drill.
- We take out the rotor. To do this, unscrew the crepes located on the stator, then detach 4 terminals from the stator contacts.
- We take out the remaining parts.
In some cases, if the problem lies in the gearbox or percussion mechanism, we additionally unscrew the end of the gearbox housing, and then carefully remove the casing made of plastic. To keep the parts in place, it is best to do this entire process with the tool on its side.
LCD projectors
LCD models are the most common today due to their affordable cost. However, apart from the low price, they can hardly stand out with other advantages. Of course, you can watch at home on such projectors, only it must be done from afar. Only multi-colored dots will be visible in the vicinity. In addition, the contrast is also poor. Do not forget that these models are initially positioned as budget models, so the lamp in the projector is installed the cheapest, and the matrix resolution does not reach HD. You can enjoy viewing on this projector only in completely darkened rooms. However, even in such conditions, due to the poor quality of the transmitted image, some particularly small details will simply not be visible.
Triple LCD projectors offer higher image quality that does not degrade even when viewed side-by-side. The use of improved image transmission technology transmits many more colors. In 3LCD projectors, image enhancement is achieved through the use of special technologies. Each color has its own monochrome matrix. First, each light flux passes through its own matrix, and then, using a prism, they are combined into one bright and multicolored image.
How a 3LCD Projector Works
Although 3LCD projectors have much better brightness and color performance than budget projectors, they have their drawbacks. Contrast is not very high compared to DLP projectors. This is due to the peculiarities of the LSD matrix. None of them, even the most expensive, are capable of providing complete color blocking, as a result, achieving deep blacks will not work.
In addition, all liquid crystal matrices require regular cold air blowing. This procedure is mandatory in order to reduce the negative effect of high temperatures on them. However, the constant blowing causes the formation of a layer of dust on the matrix, which cannot be avoided even by installing the filters and their regular cleaning.
CRT technology
This technology can be considered the oldest, since it is based on a cathode ray tube (CRT). Although CRT technology has been used for several decades, nevertheless, it is still relevant and in terms of the quality characteristics of the picture (clarity, resolution, color rendition) is not inferior to modern and more expensive methods of image formation. Another advantage of the CRT is the high reliability of electrical circuits and the duration of continuous operation of the tube, exceeding the limit of 10,000 hours.
Despite their undoubted advantages, CRT devices are still inferior in some respects to modern devices.
- The units are heavy (several tens of kilograms). If the manufacturer made them a little lighter, there would be a possibility of more convenient transportation and installation of this equipment.
- The brightness level ranges from 100 to 300 ANSI-lumens, while in modern devices the level can reach 10,000 ANSI-lumens or more. For this reason, viewing is only possible in a well-darkened room.
- To achieve good image quality, a lot of adjustments are required, and it is sometimes difficult to do without the involvement of a specialist.
Inside the CRT projector there are 3 CRTs with screens ranging from 7 "to 9". Each CRT is designed to output one color (green, red, blue) of the RGB color model.
The principle of operation of the projector can be described as follows: the input signal is divided into color components, which are involved in controlling the modulators. In this case, the intensity of the beam begins to change. At this moment, the beam, passing through the magnetic field and the deflection system, subjects the surface of the phosphor-coated screen to scanning from the inside. After that, a one-color picture is created on the screen. Further, through the lens, it is projected onto an external screen.
As a result, 3 images are simultaneously projected on the external screen, when mixed, a full-color picture is obtained.
LCoS (SXRD, R3LCD, D-ILA)
The developers of this technology have succeeded in eliminating all the shortcomings of previous models of projectors. At the same time, all their most positive qualities were preserved and improved.
Here, the image is formed, as in 3LCD-projectors, by passing rays through the matrix. However, they do not pass through the light, but are reflected from a layer of mirrors, as in DLP models. The pixel controls are on this mirrored layer behind pixels that are close to each other. This removes the rainbow effect and improves image quality.
Of course, this technology has disadvantages. Chief among them is the high price. LCoS projectors are significantly more expensive than similar DLP and 3LCD models, which have the same and sometimes even higher performance. Therefore, these projectors are currently only used by professionals to create quality presentations and installations.
Deciding which punch is better
The first electric rock drill appeared back in 1932. Since then, its design has remained practically unchanged. The main elements to this day remain: an electric motor, a percussion mechanism, a gearbox and a cartridge. Time and progress only increased the electronic muscles, along the way replacing the material of the case and mechanisms.
The main function of this device is kick. According to the method of its implementation, there are electromagnetic and pneumatic perforators. Electromagnetic beats are produced by two interacting electric coils. The reciprocating motion from the coils is transmitted to the core, which in turn acts on the drill. In pneumatic devices, a push occurs when the piston moves back and forth in the cylinder. A household rock drill is usually equipped with a pneumatic impact mechanism.
By the type of drive, the following devices are distinguished:
- Electrical network (operate from the electrical network);
- Electric rechargeable (battery operated);
- Pneumatic (used in fire and explosive works);
- Gasoline (used in road construction).
The most widespread is the electric network type with a pneumatic mechanism, it is also called a household puncher.
The number of modes is distinguished:
- Single-mode, there is only drilling mode;
- Dual-mode, drilling mode and hammer drilling mode;
- Three-mode, have a mode of drilling, drilling with a break, a mode of chiselling.
Punch device we study the nature of the impact force
The hammer drill device has design features that depend on the engine power and the type of tool assembly. Therefore, before choosing a rock drill, it is better to study it from the engine to the chuck. Having learned all the intricacies of the device, as well as minor nuances, you can determine the model and type.
The perforator device is not as terrible as the percussion mechanism as it is painted
The heart of the hammer drill is an electric motor that can be positioned vertically and horizontally. The horizontal arrangement is inherent in hammer drills of low power. Motors are positioned vertically in medium to heavy units, as the vertical design provides better cooling conditions and is less susceptible to shock loads. However, there are some exceptions that prove the rule.
The type of location of the engine affects the kinematic scheme that carries out the impact. In horizontal models, an oscillating bearing is mounted on the gearbox shaft, the outer sleeve of which is connected to the piston. When rotating, such a mechanism creates an oscillatory motion. The piston is in the chamber, in the same plane of motion with the ram. The chamber has openings for air circulation. When the drill is pressed against the concrete, it pushes the ram, which moves towards the piston, blocking the flow of air into the chamber. The piston, moving towards the ram, compresses the air between them, thus a pneumatic blow occurs. The ram moves, hits the borax, opens the circulation windows, releasing air from the chamber.
The difference between the vertical models is that the drive rotates two separate shafts. One rotates the gearbox, and the second transmits the moment to the crank mechanism. Its piston interacts with the ram in the same way as the horizontal models. The crank mechanism increases the piston range of motion, which increases the push force. Therefore, this arrangement prevails among powerful models. The gearbox of the tools under consideration is single-stage. Two-stage are very rare, they are supplied with professional devices.
The hammer chuck is not equipped with a cam mechanism like an electric drill. The SDS and SDS-max system is used to secure the drill. They differ in the number of fixing jaws, as well as in the shank diameter, 10 and 18 mm, respectively. They have the same fastening principle. The steel jaws fit into the corresponding grooves on the bit shank. This system is very convenient, the ring on the chuck has two positions: closed and open. The open petals are folded back and the nozzle can be easily inserted or removed. The closed cams secure the drill tightly.
Such attachment of the nozzle does not allow it to rotate. On the one hand, this is good, but at the same time, the likelihood of damage to the gearbox and the motor shaft when a drill wedge increases. To eliminate the negative impact on these parts, the kinematic diagram is enriched with a protective sleeve. It can be frictional, when two discs are tightly pressed against each other by a spring (rotation is transmitted by the friction force between them), and when the discs are jammed, they simply slip, opening the kinematic scheme, or gear, two half couplings have a toothed notch on the front side.
The half-couplings are pressed by a spring. When the load on the shaft exceeds the elasticity of the spring, the toothed discs slip. This system is used in the construction of a screwdriver. It is more reliable, but less resistant to wear and tear. Tooth wear reduces the trigger torque. Putting a washer or changing the spring to a stiffer one is not worth it. It will not be possible to guess the coefficient by eye, and if you overdo it, then with the next serious jamming, the gearbox will definitely fall apart.