What is a jackhammer for?
Very similar to carpentry, but with a wedge-shaped back and a slightly convex striker, hardened to a value of 45-50 units, which prevents damage when hitting a core or chisel. The range of weights is the same as for carpentry, handles are also made of various materials, as a rule, they are covered with oil-resistant linings.
A bit of theory
The main part of the energy loss goes to the kickback of the hammer, due to the appearance of elastic forces. The amount of recoil depends on the material of the hammer head and the properties of the material. For a steel tool, energy losses are about 30%, for titanium. in the range of 3. 5%. But these indicators also depend on other parameters:
- the type and shape of the striking part;
- material and length of the handle;
- tool mass;
- contact angle;
- matching the type of hammer to the operation being performed.
The last item on the list is very important. in mechanical engineering, stone processing, construction, various types of hammers of different levels of versatility are used. Among them, you can choose a tool for all occasions, for domestic and semi-professional use, and highly specialized, “sharpened” for performing one or two operations, but with the highest efficiency.
The two main parts that make up the hammer. the handle and the head. are firmly connected to each other. When moving on a massive head, rather large forces act. when sliding off the handle during an impact, the kinetic energy of the head allows it to fly several tens of meters. If at the junction there is the slightest wobble or cracks appear on the handle, the hammer must never be used. It becomes dangerous for the worker and others.
The head consists of several parts:
2. Hole for the handle (vad);
4. Nail puller;
The striker, the head striking part, is usually flat, has sufficient area and strength to withstand a significant amount of shock contacts with solid objects without deformation. The impact surface is flat or slightly convex. In cross section, it represents a square, rectangle or circle.
The back of the hammer is generally wedge-shaped. This allows you to develop a significantly greater impact force by reducing the contact area. Wedge strikes are used when it is necessary to split the material or emboss. The back part can be spherical, depending on the scope of the hammer and its main purpose.
The seat is made in the form of an oval or round through hole, the walls of which slightly expand from the center to the upper part, to exclude possible slipping from the handle. On some types of hammers, there is a forging around the bore in the form of a metal collar, which goes over the top of the handle by several centimeters. This part of the tool protects the handle from kinking when hitting too hard or inaccurately.
The head is made of hard metal by forging, casting or milling. It is protected from corrosive effects by special types of paint or galvanic coating. Before applying the protective layer, the head is hardened, in most cases selectively. The striking part (firing pin) reaches the highest hardness (up to 52 units on the Rockwell scale). Hardening is carried out by the electric induction method, which makes it possible to accurately control the depth of surface hardening. On the striker, the hardening depth reaches 3. 5 mm.
The back part (wedge or nose) is hardened up to 36. 42, and the area of the bore hole. up to 24.30 units on the same scale. The shape, weight, dimensions and other characteristics of industrial hammers are determined by GOST 11042-90 and 2310-77, which describe almost all types of hammers and their purpose.
Many manufacturers produce percussion tools according to their own specifications, which take into account most of the requirements given in national standards. The changes concern the use of new alloys, the length and shape of the handles, improved ergonomics, computer-modeled, more accurate surface treatment.
High precision tools. It does not require as much impact force as accuracy. They are produced in a wide range of head weights. from 100 to 800 grams in 50 grams increments. The striking part is in most cases perfectly flat. Rear. can be either a nailer or a simple wedge.
Handles are made not only of wood, there are metal and fiberglass, covered with rubber or polymer pads to prevent the hand from slipping.
Types and types of hammers
Sledgehammers and hammers
One of the most powerful tools is the sledgehammer. a massive head with a long handle. Sledgehammers are used to perform various operations where a high impact force and low accuracy are required. crushing stones, concrete, driving wedges and racks, forging large parts. You can see sledgehammers in Egyptian and Roman frescoes and paintings from the life of builders. In some cases, sledgehammers have been used as powerful and effective weapons.
As a rule, sledgehammers are a two-handed tool. But there are also varieties for one-handed operation in confined spaces. The production of sledgehammers is regulated by GOST 11401-75 and 11402-75. The mass of the working part of the sledgehammer is in the range of 8. 10 kg, but it can reach 16 kg.
Sledgehammers are made by forging with subsequent surface hardening up to 32 units. Forging hammers are additionally equipped with steel strips on the striking part. Small forge and construction sledgehammers with a head weight of up to 2 kg are hardened up to 50 Rockwell units.
The head of the sledgehammer itself is a rectangular parallelepiped or has the shape of a conventional hammer with a wedge-shaped back. Wedge located perpendicular or parallel to the longitudinal axis of the handle.
The bore of the sledgehammer and hammer is slightly tapered, tapering towards the bottom. The handle is inserted from above and does not require wedging; due to this form of thrust, sliding of the massive head is practically excluded. The length of the handle correlates with the mass of the head and can reach 120 cm (mostly 80. 90 cm).
When installing ceramic tiles, large mechanical loads and shock effects are not applied. As with carpentry, precision is more important here. The weight of a tiler’s hammer rarely exceeds 75 grams, the impact part is hardened to a high hardness. Such tools are used mainly for chipping off small parts of tiles when fitting to size. When used, they require precision and accuracy.
Straightening hammers and mallets
Designed for alignment of deformed sheet metal products, installation of roofs, drainage systems and other sheet metal operations. As a rule, they are made of rubber or polyurethane, but there are also models with a metal head, equipped with replaceable strikers of a softer material.
Among the straightening hammers, the inertialess version of the tool is popular, which does not give a rebound at all. Such hammers are made with a hollow percussion part, into which sand or fine shots are poured. They completely absorb the response energy of the blow and the hammer seems to “stick” to the treated surface.
Mallets are intended for carpentry or locksmith work (various types). They are made of hard wood, cast rubber or polymer materials and are designed for straightening, leveling and fitting large parts, as well as for working with chisels, chisels, wedges, cutters. Impact part. rectangular parallelepiped, handle. wood or durable plastic, fiberglass, metal, usually round.
Joiner’s mallets can be cylindrical or barrel-shaped, and locksmiths can be equipped with a wedge-shaped back. For work that requires special delicacy, the head part of the hammer can be supplemented with leather, plastic, rubber or rubber pads and nozzles.
Depending on the roofing material used, a tool with a steel or polymer striker is selected. The handle is usually wooden. Unlike straightening machines, also designed for working with sheet metal, the back of the roofer’s hammer is a sharpened wedge, like a pickaxe. It serves for punching holes in the sheet and folding folds and edges.
Hammers for installing slate roofs are different from tools for metal. they are equipped with a wider striker for slate nails and a specially shaped nail puller in the back.
Ahead behind the bump stop: nuances, tips
All bumpers are divided into 2 types:
Pneumatic. Most often it is used in complex construction and installation operations, in mines. An outlet is not required for the work. The bump stop quietly performs its functions at high humidity, is not afraid of fire and explosions. The tool is intended purely for industrial professional use, not in everyday life. The exception is small hammer drills, which function as a bump stop. An example is TOPEX 74L331. A compressor station is needed for smooth operation.
Electric. In such a bump stop, vibration is felt least of all; special skills are not required to use it. Powered by an outlet. Most popular on the market. There are both household models and professional-grade devices in the segment. There is also a minus: not suitable for objects with high levels of humidity.
There are also gasoline ones, but they are bought less often. It is necessary to focus on the power indicator (from an outlet or without it) depending on the category of work performed. So, the electric bump stop is universal, it can crush concrete in two planes, however, it is worth considering the placement of the motor.
For horizontal tasks, a tool with a vertical motor is needed, and vice versa. Hammers with a horizontal motor are the most compact, weighing up to 10 kg. These household mechanisms will not cope with complex and large-scale construction work. For roads and large construction sites, only a vertical concrete breaker is chosen.
The list of essential parameters required when choosing the best jackhammer (electric or other type) also includes:
The device allows you to change the nozzle for specific work. As a rule, attachments are included in the kit, but you can purchase them separately. Most popular tips:
- Pick-crowbar. It is with this pointed part that the bump stop is most familiar to see. Such a nozzle is used to dismantle concrete, brick, stone, and destroy asphalt. It can be used in non-standard situations, for example, to loosen the soil for its subsequent processing.
- Scapula. Suitable for removing tiles from walls or floors, removing old plaster from the surface. The nozzle really resembles a small shovel, at the end it has a significant expansion with a straight cut. The edge is sharpened and very sharp.
- Chisel. This building element is needed to cut the reinforcement, destroy the frozen ground, make a hole or a niche in the wall. It is also used when working with metal structures during their dismantling.
The ramming attachment is also suitable for the hammer. Its mission is clear from the name. to compact the soil (it is possible with stones), to close up faults in hard-to-reach places, and more.
How the fender looks and works?
The impact force here is formed by a special mechanism located under the case cover. It is he who creates the necessary shock waves, which are transferred to the chipper cutter and further, to the material, destroying it. It all works like an earthquake.
The bump stop is quite heavy, noisy and vibrates very much in the process. True, manufacturers are trying to minimize the effect of vibration, but still, with frequent and intensive use of the hammer, it negatively affects human health.
Concrete breakers are also suitable for home use, but they are more often found on large-scale construction sites or road works. If there is a need to purchase such a tool, you need to know how to choose a jackhammer: take an electric or pneumatic one, is the design important, what performance characteristics should you take into account? A competent choice will save you from inconvenience during the work process and greatly facilitate the life of the builder.
3 best electric jackhammers
- Makita HM1203C. Medium power bump stop. The chuck allows you to set the chisel in 12 positions, adjusting the angle of work. There are 5 modes of beat frequency, you can choose a suitable variation in the range of 950-1900 beats / minute. The model is equipped with protection against motor overload, the possibility of a soft start and a stabilization system to maintain the working pace during prolonged use.
- Bosch GSH 16-30. The tool of true professionals, daily production. up to 13 tons of filmed material. Has a vibration damping system that not only relieves stress from the hands, but also extends the life of the bump stop. The body of the device is made of metal parts, durable, not afraid of falls. The tool will remain unharmed even if a wall falls on it.
- Sparky К 615CE HD. This bump stop is equipped with electronics to record the force of the impact under any load. The comfort of work is ensured by an anti-vibration system, smooth start, the ability to independently adjust the force of impact. To protect against overloads there is a LED on the case, it signals overheating and possible malfunctions.
Noteworthy fenders with power supply are also produced by the companies Dnipro-M, Kawasaki, Stanley, Hilti, Zenit.
How to choose a jackhammer: 6 tips
2Need a powerful and powerful tool to smash walls, floors, and even asphalt? There is one called a jackhammer. Neither monolithic concrete, nor frozen impenetrable soils, nor brickwork, nor even the strongest stone can resist it. No obstacles on the way! With such a device, you can in a matter of moments remove the old tile from the wall, make a niche, remove the worn out road surface and much more.
The thing is useful, but not everyone knows how to choose it correctly and which jackhammer is better. Professionals reveal the secrets of a successful purchase. And for a “snack”. a rating of 6 top bumpers of different types.
3 best pneumatic bumpers
- Metabo DMH 290 Set. Lightweight, handy tool. Suitable for crumbling stone and processing steel products. There is shock absorption, which can significantly reduce vibration during operation. Quick-detachable attachments. Includes case.
- Fubag HRС 4500. Purpose of the tool. processing of concrete and stone materials. Copes well with metal. The body of the device is made of a durable composite, there is shock absorption, which is important during operation. Includes 2 attachments. Weight only 1 kg.
- Caliber OMP-815. The mechanism with an impact energy of 43 Joules perfectly crushes stones and concrete. Thanks to the metal housing, it can be used even in aggressive conditions where there is a lot of dust, moisture or explosions.
Which jackhammer is better: electric or pneumatic. it’s hard to say. They differ in the type of work, but the result will be the same. Having given preference to an electrician, you only need to take care of the presence of an outlet nearby, for a pneumatic bump stop you need a compressor.
Vibration and noise protection
Do not forget about anti-vibration systems, since the problems of dealing with vibration and noise are solved in different ways. The first thing worth mentioning is the built-in dynamic counterbalance system, which can reduce vibration by about 50-70%. There are also foam and rubberized pads, as well as handles with damper inserts and spring suspension. For example, HILTI uses the AVR (Active Vibration Reduction) system in the TE 3000-AVR and TE 1000-AVR.
Bosch GSH 5 E
For a long time our young brigade did not have a jackhammer. The rental of a percussion instrument saved the day, but, frankly, the cost of this service is quite high, given that the volume of dismantling work was constantly growing.
When the time for epiphany came, it became clear what exactly we need. The main work, for which a jackhammer was needed, was carried out during the redevelopment of apartments. to make an opening in the wall, break the brickwork. Even in new buildings it was possible to roam. Sometimes you have to knock down plaster, chop off old screeds, choose niches for a safe or an electrical panel, make large grooves for various communications.
How not to use jackhammer (power drill) [HD] (english subtitles)
For some time, we began to build cottages, where the scope of work expanded. to make a hole in the ceiling, to level the foundation, to punch an opening in the slab for the stairs. Therefore, before choosing an electric breaker, it was clear that we did not need a heavy or even medium breaker. the power of a light model could have been more than enough to carry out these works. As a result, we purchased a Bosch tool.
The Bosch GSH 5 E bump stop pleasantly surprised us with its impact force, the value of which reached 12 J at the available frequency of 3000 beats per minute, which was unattainable for this class at that time. When working with such a tool, you can have a feeling of your own greatness, because it easily copes with the destruction of concrete and other materials. As it turns out, hard work can also be enjoyed. Such power is not always needed, from which the walls in a neighboring apartment can collapse, therefore the impact frequency regulator, made in the form of a small wheel on the body, is very useful.
The electric fender reducer does not overheat, since the metal body copes very well with heat dissipation, so there is no need for pauses for cooling at all. 1100 watt motor handles all tasks effortlessly.
After the unit was plugged into the network and the start key was pressed, its heart came to life quite smoothly, while there was no overload in the network. But it won’t hit until you give it a peak load. The indicator light signals the standby mode. The start button has a lock, so you do not need to strain your fingers during continuous operation.
If the rig comes into contact with a hard material, then the bump stop will start to work a little differently, since the constant electronics are triggered, which does not allow the engine speed to fall. Service display helps monitor tool status.
The Bosch GSH 5 E demolition hammer is very convenient when working overhead, with outstretched arms and in a horizontal plane, since it weighs only 5.5 kg and its dimensions are 480×235 cm, which makes it possible to compare this unit with barrel rock drills.
It is also equipped with a very convenient additional bracket-shaped handle, which is bent at an angle, thanks to which it is possible to expand and narrow the grip, as well as rotate it 360 degrees.
The start key is made large, so it can be felt even with rough gloves. Switches are easy and precise to operate.
The anti-vibration system is also admirable. It is the best we have ever tested. It’s hard to imagine how much efficiency has been achieved in more modern models (Vibration control).
The extension block won’t get in the way under your feet, as the power cord is fairly decent in length. over, it is well insulated and flexible enough. The Bosch company also has one more know-how. the cable is connected to the fender body by means of a hinge. Due to the movable sphere, a break in the cord is excluded, which will be very useful when working in pinched places.
The flat lance-blade can be rotated in one of twelve positions to make it possible to make convenient and accurate chiselling in confined spaces. The Bosch company called this system “Vario-Lock”, it is used in all Bosch chippers and rotary hammers.
In this model of the bump stop, the SDS-max cartridge is used, since large equipment is needed to transfer shock energy of this type.
Also, the jackhammer is equipped with a capacious, high-quality case.
The Bosch GSH 5 E demolition hammer has served faithfully for several years. At one time, we spent about 700 on it, but it fully paid off every cent invested in it. In addition, he is not even going to retire yet, but will work as before.
Of course, this model has already been discontinued, but if necessary, we will take another similar model from Bosch weighing about five kilograms.
Maximum single impact force is another important characteristic of an electric bump stop. The given force is calculated in joules. The more important the impact force is, the more capabilities a particular model has and the more durable material it can destroy.
For light bumpers, this figure is at around 3-8 joules, and for powerful concrete breakers it can exceed 60 joules (Makita HM 1810, Bosch GSH 27 VC). Sometimes a small impact force can be compensated for by a high frequency of the striker, which carries out reciprocating movements. For example, the Bosch GSH 5 CE, which has an impact force of 8.3 joules, can do 2,900 beats per minute, while the Makita HM 1810, whose impact power is 63 joules, can only do 1,100 beats per minute. Summing up, we can say that the number of blows and the force of the blow are the main indicators of the performance of the tool, but a lot depends on their correct ratio.
Differences between electrical fenders
It is necessary to approach the choice of an electric bump stop very carefully, since it has a rather high cost. Most often, when choosing an electric tool, you need to start a conversation with which model you need. household or professional. Although, there is practically no amateur class for a jackhammer. But it should be borne in mind that almost all manufacturers offer hammers that are designed for a wide variety of tasks.
Control and indication systems
An electric jackhammer is a high-tech and rather expensive tool, which must have a number of electronic systems that need to ensure its functionality and reliability. One of such systems is the regulation of the impact frequency, which can be performed either by the regulator, in the presence of a start lock, or by the degree of pressing the button. By the way, the lock of the start button is a rather important part, thanks to which you can release the trigger during continuous long-term operation. If the start is made in the form of a slider, then it does not need to be fixed in principle.
Some models have a mechanism that disables the shock function when idling. standby mode. This mode is able to increase the resource of the shock unit.
How to Use a Demo Hammer / Jack Hammer
The inrush current limitation must always be triggered when the heavy-duty fender is switched on This is done so that there is no spike in power consumption. For example, DeWALT D25899K has this function.
Many manufacturers complete their products with various control devices (indicators, displays) that signal the wear of the brushes or the need for service. If the brushes are not replaced in time, they can turn off on their own, preventing damage to an expensive motor. The condition of the plug and cord can also be monitored.
Classification of Electric Breakers
This type of tool can be divided into three groups. The first includes light jackhammers, which weigh up to 5 kilograms. They are lightweight, compact and relatively versatile; in the horizontal plane they are very convenient to work with. If you are faced with extremely difficult tasks, then it is better to use medium (weight from 5 to 10 kg) or heavy (up to 30 kg) bumpers, which are also called concrete breakers. Such fenders are very narrowly specialized and in a horizontal position it is rather difficult to work with them. These fenders are primarily intended for foundation and earth operations, as well as for road works directed vertically downward. Accordingly, these fenders can be classified into horizontal and vertical. The division of hammers by weight is quite reasonable, since this characteristic indicates the massiveness of the parts and the power of the tool.
For example, the weight parameter is already being introduced into the product labeling by Bosch (USH 27, GSH 5 CE. respectively 27 and 5 kg).
One of the main indicators, of course, is the engine power, which ranges from 500 to 2000 watts. The higher the power of the tool, the higher the performance of the jackhammer will be and the higher the frequency and force of impact can be obtained at the output. power will allow you to operate the tool continuously for a longer time, as well as use larger tools. But this practically does not apply to Chinese products, since Chinese tool manufacturers most often install the most powerful motors on their products, but usually it turns out that extra watts cannot be used.
How to choose an electric jackhammer for construction work?
This article will describe how to choose an electric jackhammer, for which a jackhammer is needed on a construction site, what are the differences between different models of this percussion tool.
Probably everyone has seen a jackhammer in his life. This is the same noisy and large unit that miners and road workers in old Soviet films held in their hands. Demolition hammers began to be used in tunneling and in the mining industry at the beginning of the twentieth century. But over time, the technology of rock drilling and obtaining strategic raw materials has changed a lot and therefore more productive devices and machines have replaced hammers.
An interesting fact is that electric jackhammers were originally created, but they could not be used in the mine due to possible arcing, which could lead to a fire or even an explosion. In addition, in those days, technology did not allow achieving sufficient reliability and power from an electric tool. For this reason, pneumatics dominated for a long time, where energy from the compressor to the percussion mechanism is supplied with the help of compressed air through hoses.
And the jackhammer started a new life, but already in construction. The world leaders in the production of hand tools arrived just in time, making the electric chipper affordable, reliable, safe, convenient and powerful. He began to systematically conquer the market from gasoline, pneumatic and hydraulic driven hammers. Among the advantages of the electric bump stop are ease of maintenance, low vibration and noise levels, as well as environmental friendliness.
With its help, on a construction site, you can carry out most of the dismantling work: cutting metal, chiselling ice and frozen soil, breaking asphalt, making large holes and openings, destroying concrete (screeds, floor slabs, old foundations, monoliths, blocks), dismantling stone and brick walls. But the bump stop is also suitable for pure creation. with the help of a tamping sole, you can compact crushed stone cushions and soils, hammer in cylindrical and serrated rods with a crutch sledgehammer. A simple hammer drill will not help here, since it is less powerful than a jackhammer, which, moreover, has no drilling function, and all the energy is sent to the blow.
Do not be surprised that some models have a plastic gear case, while others have a metal one. Usually the plastic is chosen to reduce the weight of the horizontal tool. But do not be afraid about this, because the material used is not only lightweight, but also quite wear-resistant and durable. An example would be the Makita HK 0500 bumper. For powerful devices, metal parts made of magnesium alloys and aluminum are often used.
The chuck designed to fix the shank may also differ. For some manufacturers, the lightest models work with SDS-plus tooling, but most of the fenders work with SDS-max chucks, which can be up to 26 mm in diameter. The most powerful models use lances with a diameter of up to 30 mm and a hex shank (Hitachi H65SB2).
Sometimes you have to work from a variety of positions, so if the tool has the ability to select and fix different positions of the rig, it will only benefit. The most common twelve positions are used, spaced every 30 degrees.
Before choosing an electric jackhammer, you should pay attention to the ergonomics of the product. It is very important to have an additional handle, which can be either D-shaped or straight. It must be comfortable for the operator and have many mounting positions.
If many models of the same class are so similar, how do you choose the model of the jackhammer that works best? We can say that all the main companies that are engaged in the production of construction tools have long been known and each of them makes quite decent jackhammers. The quality and technical characteristics of their products are approximately at the same level. In this area, innovations appear extremely rarely and all competitors quickly learn about them. It makes no sense to choose a tool based on individual parameters, since most often developers carefully balance their products.
For this reason, when choosing a bump stop, you need to build on the features of the front of work and specific tasks, as well as on personal preferences in the field of design and ergonomics.
The main criterion by which the bumpers can be divided is weight. light, medium and heavy.
Some builders prefer cheap Chinese tools, which are much cheaper than branded ones. But this approach is often not justified, since you can incur forced losses from downtime, and the level of security with the performance of Chinese tools is much lower.
How to choose an electric jackhammer: professional recommendations
We continue the series of articles about the builder’s tool, within which we have already discussed screwdrivers, chain saws, hammer drills, jigsaws, cross-cut saws, angle grinders. What is an electric jackhammer for on a construction site? How do different percussion models differ? How to choose the right one? Read about it today.
Probably everyone has seen a jackhammer at least once in his life. Yes, this is the same big and noisy unit in the hands of a road worker or a miner from old Soviet films. In the early twentieth century, jackhammers began to be used in the mining industry and in tunneling. But over time, the technologies for obtaining strategic raw materials and driving rocks have changed dramatically, hammers have been supplanted by productive machines and devices.
It is interesting that, contrary to popular belief, it was the electrical “bumpers” that were created first, but due to possible sparking it was impossible to use them in the mine, since there is a great danger of explosion or fire. In addition, the technologies of that time did not make it possible to achieve sufficient power and reliability from an electric tool. For a long time, pneumatics became dominant. when energy from the compressor to the percussion mechanism is transmitted through hoses using compressed air.
The jackhammer has been given new life in construction. Just in time, the world leaders in the production of hand tools took the first step, the electric chipper became powerful, convenient, safe, reliable, almost affordable. He is systematically gaining ground against hammers with hydraulic, pneumatic, gasoline drives. Environmental friendliness, low noise and vibration, easy maintenance can be written into the asset of the electric jackhammer.
At construction sites, it is used to carry out most of the dismantling work: dismantling brick and stone walls, destroying concrete (blocks, monoliths, old foundations, floor slabs, screeds), making large openings and holes, breaking asphalt, chiselling frozen soil and ice, cutting metal. However, for pure creation, the bump stop is also suitable. soils and crushed stone cushions are compacted with a ram sole, serrated and cylindrical rods are hammered with a crutch sledgehammer. An ordinary puncher is indispensable here. A jackhammer is much more powerful than a hammer drill, it has no drilling function, so all the energy is invested in the blow.
BOSCH GSH 5 E
For several years our young brigade suffered without a jackhammer. They got out of the situation by renting a percussion instrument, but it should be said that the cost of such a service cannot be called humane, especially when you consider that the volume of dismantling work was constantly increasing. By the time of our epiphany, we already knew exactly what we needed. The main work that we carried out with a jackhammer was connected with the redevelopment of apartments. to break the brickwork, to make an opening in the wall. Even in new buildings there is a place to roam. A little less often it is necessary to make large grooves for communications, choose niches for an electrical panel or a safe, chop old screeds, knock down plaster. Over time, they started building cottages, here the scope of work expanded. somewhere to punch an opening for a staircase in a slab, somewhere to level the foundation, somewhere to make holes in the ceilings. It was obvious that we did not need a heavy and even medium chipper. in all cases lacked the power of light models. So, in 2006, our arsenal was replenished with heavy artillery from the beloved Bosch company, although not so heavy.
The GSH 5 E bump stop immediately impressed with its impact force, which reached 12 J at a possible frequency of 3000 bpm, which was at that time unattainable for this class. While working with such a tool, a feeling of one’s own greatness involuntarily arises, so easily it copes with the destruction of concrete and other materials. It turns out that hard work can be fun! Of course, such power is not always needed, especially if you do not want the walls to collapse in the next apartment. Here the beat frequency regulator in the form of a characteristic wheel on the body comes in handy.
The gearbox does not overheat, its metal body removes heat well, pauses for cooling the tool are not needed at all. 1100-watt motor handles its tasks without difficulty.
After turning on the unit to the network and pressing the start button, its heart comes to life smoothly (no overload in the network is felt), but until you put the load on the peak, there will be no shock. The standby function is confirmed by the indicator light. The start button itself is fixed, so there is no need to strain your fingers during continuous operation.
As soon as the rig rests against a hard material, the bump stop starts to work a little differently, this is the constant electronics that does not allow the engine speed to drop. Service display helps monitor tool status.
The BOSCH GSH 5 E jackhammer is very convenient for working horizontally, with outstretched arms and even overhead, its weight is only 5.5 kg, and its dimensions (480×235 mm) generally put this unit on a par with many barrel rock drills. The set includes a very convenient bracket-shaped additional handle. It is bent at an angle, which allows not only turning it 360 °, but also narrowing or expanding the grip. The start key is large, it feels well even in rough gloves. All switches work smoothly and smoothly.
The vibration protection system turned out to be at the level. one of the best among those that I had a chance to test. Imagine how effective it is in 2012 models (Vibration Control).
The power cord is quite long, so the extension block never gets in the way. It is quite elastic, but at the same time it is well insulated. Another pleasant “Bosch” know-how is the articulated connection of the cable to the fender body. Movable sphere prevents cord breakage, especially useful function for pinched places.
The flat spade can be rotated to one of 12 positions for precise, comfortable chiselling in tight spaces. Bosch has named this system “Vario-Lock” and is successfully used on all its rotary hammers and hammers. The cartridge was used SDS-max, here, in fact, no surprises, because to transfer such impact energy, large equipment is needed.
The hammer comes with a high-quality roomy case.
The BOSCH GSH 5 E jackhammer has served faithfully for six years. We spent about 700 on it in due time, but did not regret for a single cent of this amount, everything paid off with interest. And this hammer is not going to retire, probably the same amount will work. This model, of course, has already been discontinued, but we are not going to invent anything when the time comes. we will take the GSH 5 CE, or what else BOSCH will offer in the region of five kilograms.
How electrical fenders can differ
An electric bump stop is not cheap, so you need to be very careful in choosing it. Usually, considering the criteria for choosing a particular electric tool, we start the conversation with whether we need a professional or household model. For an amateur-grade jackhammer, it’s not. But it should be borne in mind that almost all manufacturers of electrical tools offer chippers designed for various tasks.
There are three groups of this tool. Lightweight jackhammers (weighing up to 5 kilograms) are relatively versatile, they are compact and lightweight, it is convenient to work with them in a horizontal plane. To solve extremely complex tasks, you should pay attention to medium (5-10 kg) and heavy (“concrete breakers”. up to 30 kg) bumpers. They are highly specialized, it is difficult to work with them in a horizontal position. Such a tool is intended for soil and foundation operations, road works in the “vertical down” position. Accordingly, there is a classification into vertical and horizontal hammers. The division by weight is quite reasonable, since this indicator, as a rule, speaks about the power of the tool, the massiveness of the parts. For example, the BOSCH company introduces a weight parameter in the product labeling (GSH 5 CE, USH 27. 5 and 27 kg, respectively).
BOSCH 5 CE Professional
Motor power (from 500 to 2000 W) is, of course, one of the main indicators, the higher it is. the more productive the jackhammer will be, the greater the impact force and its frequency can be obtained at the output. High power allows for a longer time of continuous operation of the tool, use of larger equipment. However, this circumstance almost does not apply to the products of Chinese brands. Manufacturers from the Middle Kingdom usually install the most powerful motors on their instrument, but for certain reasons, they cannot get dividends from the extra watts.
The most important characteristic of an electric jackhammer is the maximum force of a single blow, which is calculated in joules. The greater the impact force, the more opportunities a particular model provides, a material of greater strength can be destroyed. This indicator for light bumpers can be at around 3–8 J, while for powerful concrete breakers it can be more than 60 J (BOSCH GSH 27 VC, Makita HM 1810). In some cases, a small impact force is compensated by the high frequency of the striker’s reciprocating movement, for example, BOSCH GSH 5 CE (8.3 J) performs 2900 beats per minute, and Makita HM 1810 (63 J). 1100 beats / min. So, the power of the blow and the number of blows per unit of time are the main indicators of performance, but much is decided by their correct ratio.
An electric jackhammer is an expensive high-tech tool that must have a number of electronic systems to ensure its reliability and functionality. One of them is to adjust the beat frequency. It can be performed either with a button (according to the degree of pressing), or with a regulator, if there is a start latch. By the way, the release button of the trigger is a very important detail that allows you to release the trigger during long continuous operation. Slider start does not require any fixing in principle.
In some models, a mechanism is installed that turns off the idle shock function. the so-called “standby mode”. This increases the resource of the striking unit.
When the powerful fender is turned on, the inrush current limitation is triggered so that there is no jump in power consumption (DeWALT D25899K).
Most manufacturers arrange their tools with control devices (displays, indicators), signaling the need for service or wear of the brushes. If the brushes are not replaced in time, they can turn off on their own so that the expensive motor is not damaged. The condition of the cord and plug can also be monitored.
How Does a Jackhammer Work?
Separately, it should be said about anti-vibration systems. The problem of dealing with noise and vibration is solved in different ways. First of all, it is a system of built-in dynamic counterweight. already with its help it is possible to reduce vibration by 50–70%. To this are added handles with spring suspension and damper inserts, rubberized and foam pads. For example, HILTI offered an Active Vibration Absorption (AVR) system. TE 1000-AVR or TE 3000-AVR (68 J).
Do not be surprised that some models of jackhammers have a metal gear housing, and some are made of plastic. This is done to reduce the weight of the horizontal tool. This should not cause concern, since the material is not only lightweight, but also very durable, wear-resistant. As an example, let’s take the “baby” HK 0500 from Makita. Powerful devices proudly shine with metal parts made of aluminum, magnesium alloys.
The type of chuck for fixing the shank may differ. Ultra-light models from some manufacturers can work with SDS-plus equipment, most of the fenders are equipped with SDS-max cartridges (up to 26 mm in diameter), heavy-duty models are designed for lances with a hex shank and up to 30 mm in diameter (Hitachi H65SB2).
Sometimes you have to work in a wide variety of positions, so it is often very useful to be able to select and fix a certain position of the rig. Typically 12 positions are available. every 30 °.
When choosing a hammer, you need to pay attention to the ergonomics of the product. An important role here is played by an additional handle, which can be either straight or D-shaped. In any case, it must have a large number of installation positions, be convenient for a particular operator.
So how do you choose a specific model of a jackhammer, because they are so similar in the same class? One thing can be said, the main manufacturers of construction tools and equipment are known, they all make decent bumpers. Their products are approximately at the same quality and technical level. Innovations in this area appear very rarely and quickly become the property of the public, or rather competitors. There is no point in making a choice according to individual parameters, everything is usually balanced by the developers.
That is why the choice should be based on the specific tasks and features of the work front, on personal preferences regarding the brand, issues of ergonomics, design, if you like. The main criterion can be considered the weight class. light, middle and heavy class.
Some builders prefer to arm themselves with cheap Chinese tools, which are several times cheaper than “branded” ones. They motivate their choice with the words: “I will buy three of them for the same money.” But this approach is far from always justified, especially since such a tool also brings losses from forced downtime, and its performance with a security level, as a rule, is much lower.
Demolition hammer power
This type of equipment is offered by manufacturers in three main varieties. Among them:
Electrical options are the most common and effective. Their advantages include low vibration and noise levels. Among the disadvantages are the inability to use in places with high humidity, as well as limited mobility due to the need for power supply. These types of jackhammers, in turn, are classified according to the working position and are:
The pneumatic bump stop is a type used in the course of heavy repair and construction work, which is especially widespread in mines. Among the advantages are the ability to use in humid conditions, independence from the power source, safety.
A gasoline unit is the most mobile type of equipment that is completely independent of the mains and does not require a compressor. The main field of application is road work, drilling, punching sleepers. The disadvantages include the inability to work in closed rooms due to emissions, as well as an increased noise level.
How to choose the right jackhammer?
The jackhammer has become today an indispensable tool in the arsenal of every builder or repair specialist. In addition, such a functional and high-performance equipment may also be required for home craftsmen seeking to independently maintain order in the house or on the site. Consider the main characteristics of this device, as well as the principles of equipment selection.
Weight and dimensions of the tool
These indicators are completely interconnected. In particular, devices are distinguished:
- lightweight, weighing 5-6 kg;
- medium. up to 10 kg;
- heavy, weighing up to 30 kg.
This indicator determines the boundary thickness of the material with which the tool can work, as well as the duration of continuous use of the tool. In particular, the approximate classification is as follows:
- models up to 1200 W. used for individual work;
- up to 1600 W. used for working with brickwork, and also capable of handling concrete and stone;
- options over 1600 W are used for punching asphalt and soil.
The main purpose of the tool
A jackhammer is a handy piece of equipment, the task of which is to break a hard surface. The technique is especially often used to work with the following types of materials:
- asphalt, etc.
Let’s figure out the approach to choosing a device.
The pike is the main working tool of the technique. Today, manufacturers offer:
Each type of working tool is designed to perform a specific type of work, ranging from stripping walls from plaster, pumping by removing asphalt and compaction of soil. It is recommended to choose based on your own needs, as well as the recommendations of the equipment manufacturer.
Strength and frequency of impacts
This indicator depends on the power and affects the entire operation of the equipment. In addition, there is an inversely proportional relationship between strength and frequency. the higher one indicator, the other, respectively, lower. Demolition hammers are divided into the following categories by impact force:
- lungs, with a force up to 15 J;
- medium. in the range from 30 to 35;
- heavy, the strength of which varies from 50 to 60 J.