A hammer drill is a very the right tool, used for drilling various holes. In its principle, the tool is similar to an impact drill, but these devices are not interchangeable. In this article we will deal with the problem - how to choose a suitable hammer drill for household work, which device to choose for apartment renovation, and also consider all its defining characteristics.
General information
A hammer drill is a device that allows you to drill holes of various sizes and depths in various materials. The intended purpose of the device is drilling materials that have high strength and rigidity (for example, concrete). Today, the most common types of these devices are devices with pneumatic and electric mechanisms, which provide impact drilling of material. Many consumers are concerned about the question: “How to choose a hammer drill for the home?” Uncertainty comes at the sight of a large assortment of proposed models. After all, each of them differs in performance, as well as various technical features. Therefore, to choose a good rotary hammer, you need to consider a number of factors.
Impact drill or hammer drill?
These two devices that need to be repaired have fairly similar parameters, but at the same time they are different.
- A drill is a smaller and less weighty device, usually used for drilling not very durable materials. Its hammer function provides very little assistance when drilling.
- The hammer drill, in turn, has greater drilling and impact power, while also having the function of a hammerless drill. When purchasing a device, you can save money that you would have invested when purchasing both devices. Powerful drills used in the devices will allow you to quickly and easily make the necessary holes in shape and depth.
How to choose the right power
The power of the device is one of the basic parameters. The market offers a fairly wide range of device powers: from 450-500 W to 2000-2500 W. As a rule, models with a power of 450-600 W are suitable for the home. All models with higher power can be called professional. Such devices allow faster and deeper drilling. For infrequent drilling work, a low-power model can be used.
Deciding on the type of device
The choice of a good hammer drill is influenced by its engine layout.
There are two such types:
- Model with a horizontal engine, suitable for short and narrow drillings. In such varieties, the engine is located along the shock axis, which contributes to a low level of cooling. During long-term operation, this type of engine must be allowed to cool, otherwise it may fail.
- Vertical engine model. In such devices, the engine is located, accordingly, perpendicular to the impact axis. These devices have the advantages of higher power and no need for constant cooling. Therefore, such varieties are more often used in conditions where uninterrupted operation and high impact power are required.
About the force of impact
Impact power is one of the determining parameters when choosing a reliable device. However, greater power provides greater tool productivity, and therefore greater energy consumption. The greater the working power, the deeper and larger in diameter it will be possible to drill. At the same time, we should not forget that such high-power devices will have large dimensions and carry a large mass.
How to choose a hammer drill for concrete
When choosing the required model, you should pay attention to its markings. Concrete requires the marking – SDS+. With this device you can not only pierce concrete, but also stir the solution and tighten bolts. Also in technical characteristics You should pay attention to the maximum permissible drill size. For various materials, be it brick or concrete, there are drills suitable for a particular material. Plus to all this is the high power of the device itself.
Preferred Power Source
There are two basic types of power sources: battery-powered and mains-powered. When working at height, it is not always possible to connect to the mains. Therefore, in such conditions it is most effective to use models that run on a battery. The battery itself must have a high capacity, since shock power will require a lot of energy consumption. The main feature of these types of hammer drills is the price indicator. Battery-powered devices are much more expensive than mains-powered devices.
How to choose a Bosch rotary hammer
Today, many companies selling equipment for repair recommend choosing a good hammer drill in favor of the German giant of power tools - Bosch. It has been on the lips of every person for a long time. The main feature of this brand is a reliable and high-quality product. In order to give advice on choosing a reliable Bosch rotary hammer, you need to understand their markings. You can find the following designations: PBH or GBH.
- G – device for professional use. R – device, used for domestic use.
- The numbers indicate the weight of the tool. (example: 3-40, 2-32).
- Capital letters: d – suitable for chiselling, f – with replaceable chuck, r – has reverse.
When purchasing company products, carefully read all the technical characteristics of the tool so as not to overpay for unnecessary equipment.
A little about additional characteristics and weight
The lighter the device, the simpler and easier it is to work with. Many existing household models are light in weight (3.5-4 kg). Among other additional devices, it is worth highlighting: the ability to smoothly unwind the drill, adjust the rotation speed, and protect against jamming of the drill.
About choosing a drill
Why is idle speed so important?
The main purpose of the drill is to work with concrete. The difference between a drill and a drill lies in the characteristic tip, manufactured according to the SDS standard. Drills with special attachments (crowns) are suitable for various purposes. On each drill, its dimensional characteristics are indicated, and on the installation structures, it is indicated which drill (in diameter and length) should be used to drill the required holes.
A tip for choosing a reliable hammer drill is to choose a kit that includes: the device itself, a drill and a case for convenient transportation and storage of the tool. It is recommended to give preference to well-known companies that have proven themselves to be the best, and their products are of excellent quality.
Rating of the best hammer drills
The best professional rotary hammers
We have collected almost all models of professional rotary hammers available on the market with a horizontal motor and an SDS+ chuck and identified the best among them based on their characteristics
- Makita HR5001C
- Makita HR5201C
- Makita HR4501C
- Makita HR5211C
- DeWALT D 25601 K
- Bison ZPME-1250EK
- Makita HR5210C
- Hitachi DH45MR
- DeWALT D 25762 K
The best hammer drills for 5000-6000 rubles
A regular electric drill drills straight holes in wood, plastic and metal. The rotation mode with impact makes it easier to work with hard materials, but it is better to entrust work with concrete and stone to a special drilling tool - a hammer drill. Read our article about how to choose a hammer drill for your home.
Rotary hammer or impact drill?
All modern electric drills have a hammer drilling mode. Can a drill compete with a hammer drill in processing hard materials - concrete and stone? Our answer is clearly negative. The fact is that the impact of the drill is very weak; its strength is not even indicated in the technical specifications.
Ratchet wheels bouncing over each other The picture shows how the drill is structured: the reciprocating motion of the chuck is provided by ratchet wheels, which jump over each other as they rotate. When drilling, this is felt as a slight vibration of the tool. To get at least some effect, you need to press the drill into the wall with a force of 10–15 kilograms.
Another thing is a hammer drill. He drills a hole in any concrete, just like in wood. It's all about the impact force, which reaches tens of joules. Pneumatics help develop such strength.
Air pressure increases impact energy The diagram shows one of the design options for the hammer drill. The electric motor rotates the shaft on which the swing bearing is mounted - it is also called “drunk”. The bearing is connected to the wall of the air cylinder. Inside the cylinder, an air gap separates the flying piston from the wall, to which the firing pin is attached, acting on the tool. Due to the rocking of the bearing, the pressure in the cylinder either increases or decreases. Due to air pumping, the impact force on the striker increases significantly.
The first hammer drill was invented in the mid-19th century for miners. A hand-held drilling machine was breaking off pieces of rock in the mine. The electric hammer appeared in 1932.
Despite the fact that the drill and hammer drill are similar in appearance, they are completely different tools. A DIYer's closet, of course, should have an electric drill for drilling holes. But, if you are renovating an apartment with concrete walls, your plans include installing sockets, hanging shelves and chiseling grooves, we recommend taking a hammer drill - you will spend ten times less effort on putting the apartment in order.
The disadvantage of a hammer drill is a loud rattling sound that spreads throughout the house so that the source cannot be localized.
A hammer drill is more expensive than a drill, but your doubts will disappear as soon as you make your first hole and feel what this powerful machine is capable of.
Criteria for selecting a rotary hammer
When going to the store to buy a hammer drill, determine in advance what holes you are going to drill: whether you are installing open sockets (5 mm), pulling a cable (10 mm) or pulling an inch pipe through the wall (31 mm); Do you need a jackhammer to knock down old tiles?
Impact energy
The main parameter of a hammer drill is the energy transferred by the striker to the processing tool; it is measured in joules. The larger this value, the larger the hole the device can make. However, there is no need to chase numbers; a machine with an energy of 27 joules is similar to a jackhammer of road workers and weighs almost 12 kg. To drill holes with drills up to 30 mm in diameter, an energy of 1.5–2.5 joules is sufficient.
Hammer weight
The weight of the device is directly related to the impact energy. They are conventionally divided into three categories: light (up to 4 kg), medium (4–5 kg) and heavy (over 5 kg). The smaller the weight of the device, the easier it is to hold in your hands, but the impact energy of a machine weighing 2 kg will be 1.4 joules - this is enough to work with a drill up to 18 mm in diameter.
The lightest hammer drills are almost no different from an electric drill. For them, nozzles are produced with a jaw chuck that clamps simple drills. This versatile two-in-one device will save you money.
Engine power and shaft speed
The industry produces rotary hammers with power from 500 to 2000 W, but this parameter is not decisive. Manufacturers select the optimal power for each model. If you are drilling a hole in a concrete wall with a depth of more than 50 cm, we recommend using a machine with a motor of at least 1 kW. The friction in the wall is very high, the slightest distortion and the low-power engine will stop.
The spindle rotation speed is also not important; it ranges from 600 to 1.5 thousand revolutions per minute. The operating principle of the hammer drill is impact destruction of the material; rotation of the drill is only necessary to remove dust from the processing area. Rotating too quickly will increase tool wear.
Useful function of the hammer drill - automatic adjustment rotation speed. The electronic circuit adjusts the speed to the density of the material being processed.
Operating modes (table)
Modern rotary hammers support three main operating modes (drilling with impact, drilling without impact, and chiselling). In stores you can find devices with different combinations of these modes. As a rule, rotary hammers with one and two modes are cheaper.
| Mode | Application |
| Drilling without impact | In this mode, the hammer drill works like a regular drill, drilling holes in wood, plastic or metal. Tool translation is disabled. |
| Impact drilling | The main operating mode of the hammer drill. The drill makes a reciprocating motion, breaking off pieces of concrete. Dust and crumbs are removed by the rotating spiral groove of the drill. |
| Impact without rotation (chiseling) | In this mode, the processing tool does not rotate. Instead of a spiral drill, a chisel, chisel or pick is used. Hammer chips away tiles or cuts down a piece of the wall. |
| Setting the bit to the desired position | To work in hard-to-reach places, it is important that the fixed bit is in the specified position. Manufacturers sometimes highlight a fourth hammer drill mode - the ability to place the tool at a certain angle. |
Chuck type
De facto standard for small and medium hammer drills Bosch has developed SDS plus and SDS max chucks specifically for rotary hammers. In them, the tool is clamped instantly and never unscrews itself (unlike jaw chucks).
The most common cartridges are SDS plus - approximately 60% of rotary hammers. They are designed for drills with 10 mm shanks and are used in light and medium-sized tools. SDS max cartridges are used in heavy hammer drills, for drills with a diameter of 20 mm or more.
We recommend taking home devices with SDS plus cartridges; drills and augers, shovels and chisels, crowns and attachments are available for them. Stores sell jaw chucks with such shanks - your hammer drill will turn into a universal drill.
Engine location: vertical or horizontal
Structurally, rotary hammers come with a horizontal engine and a vertical one.
The first is similar to an electric drill in the shape of the body and the position of the controls: long and narrow, with a short handle and trigger. This tool is convenient for getting into a tight place - a closet or an air duct. When drilling deep holes, the machine moves smoothly and the drill moves less. But with such a hammer drill it is difficult to chisel the ceiling and cut grooves - you have to turn the hand inside out, your hands get tired quickly.
On the left is an example of a hammer drill with horizontal engine, on the right - with vertical A vertically mounted engine takes up less space and is cooler. The machine fits into your hands like a Kalashnikov assault rifle, is stable during operation and has excellent control. Thanks to the position of the operator's hands on the same axis with the chisel, it is convenient to work with the hammer drill both from the waist and with one hand. The groove from floor to ceiling is cut in one go without any fatigue.
Additional functions
A good hammer drill is equipped with additional functions that increase the convenience and safety of working with the tool.
| Additional feature | Why is it useful? |
| Smooth start | When the commutator motor starts to rotate, electrical network An increased (starting) current occurs. The electronic circuit will smoothly increase the voltage on the motor and will not overload the network. |
| Release clutch | The drill crashed into a stone and got stuck - common occurrence when drilling deep holes. To prevent the winding of the commutator motor from overheating, the coupling mechanically disconnects (disengages) the drill from the motor shaft. |
| Shaft reverse | If a twist drill gets stuck in a wall, just put it in reverse and it will unscrew itself from its difficult position. |
| Automatic speed control | Electronics changes the number of shaft revolutions depending on the load on the tool and maintains them at the optimal level |
| Ruler-limiter | The ruler is attached to the body of the device and is graduated in units of length. It will hit the wall as soon as the drill has sunk to the specified depth. |
| Vibration protection | The hammer drill vibrates during operation. To protect the operator's hands from vibration, the tool handle is isolated from the body by a vibration-damping spring. |
| Carrying case | The tool is protected from dust and damage in a plastic case; spare parts and cutting tools are also placed there. |
| Equipment | A good manufacturer includes several drill bits, spare carbon brushes for the motor, lubricant for the shanks, and a jaw chuck in the hammer drill kit (puts it in the case). |
Did you know that a hammer drill can work as a construction mixer? Nozzles for mixing cement or tile adhesive are available for the SDS plus cartridge.
Power supply
Most hammer drills on store shelves are powered by an electrical outlet. These tools create enough impact energy for serious work. However, there are battery powered models. Their disadvantages are obvious - low impact energy and short operating time. Choose such a hammer drill only if you know why you need it: a house made of aerated concrete is being built in a field, there is no light supplied to the site, and sockets need to be installed.
To summarize: the characteristics of the ideal tool for the home
There is no point in buying a professional device for your home that can crumble monolithic slabs entire shift, so we recommend purchasing mid-range devices. The most famous and best brands are Makita and Bosch, but you can take Sturm, Hitachi or Interskol.
Life shows that a typical repair plan will include hanging shelves, installing sockets, knocking down tiles, and the diameter of the holes made will not exceed a half-inch pipe (21 mm).
When installing a split system, the usual hole diameter is external wall- 65 mm, this task is for professional tool. For installation indoor unit A less powerful hammer drill will do.
- Power: 500–1000 W.
- Impact force: 1.5–2.5 joules. This energy is enough to drill concrete and cut grooves in walls. If you need to break a wall, you should use a tool with more energy.
- Operating modes: simple drilling, drilling with impact, drilling without impact.
- Protective coupling. If you are working with complex material - Soviet concrete slabs with stones and reinforcement, drill deep holes of large diameter, the drill may jam. The coupling will protect you from injury, and the device from overheating.
- SDS plus cartridge. A wide selection of attachments, drills and chisels with this shank. Quick tool change. Reliable fastening- the tool does not fall out of the chuck.
Rating of popular models
The table shows the important characteristics of popular rotary hammers and gives a brief assessment of these models.
Table: the best hammer drills for home use
| Model (Brand/Factory) | Impact energy (J) | Weight, kg) | Power (kW) | Operating modes | Additional features | Price, rub.) | Max. concrete drill diameter (mm) | A comment |
| Makita HR 2450 (Japan/China) | 2,7 | 2,4 | 0,78 |
|
| 6 900 | 24 | Reliable and durable tool from a well-known manufacturer, good price/quality ratio. |
| Bosch GBH 2–26 DRE (Germany/Germany) | 2,7 | 2,7 | 0,8 |
|
| 9 000 | 26 | High quality German instrument. Disadvantage: high price, expensive spare parts. |
| SPEC-BPE-620 (Russia / China) | 2,65 | 2,4 | 0,65 |
|
| 2 700 | 24 | Inexpensive tool for home. |
| Sturm RH2517 (Germany/China) | 5,0 | 5,65 | 1,7 |
| 6 800 | 36 | Compact and powerful device with a vertical motor. Good equipment, affordable price. |
|
| AEG KH 28 Super XE (Germany/China) | 3,1 | 2,8 | 1,0 |
| 12 700 | 28 | A reliable tool for professionals. The price is too high for the house. | |
| DeWALT D 25133 K (USA/China) | 2,9 | 2,6 | 0,8 |
| 7 800 | 26 | Lightweight tool suitable for home use. | |
| Energomash PE-25500 (Russia/China) | 2,0 | 2,45 | 0,6 |
|
| 2 900 | 20 | An inexpensive device for the home is to drill holes for shelves and cornices. |
| Sturm RH2550 (Germany/China) | 2,1 | 2,7 | 0,55 | Protective coupling. | 2 900 | 20 | Inexpensive tool for home repairs. The disadvantage is the meager equipment. | |
| Sturm RH2565 (Germany/China) | 3,4 | 5,0 | 0,650 |
|
| 4 700 | 26 | A powerful and inexpensive tool for all types of work. Good equipment. The case with a vertical engine does not fit into all the cracks. |
| Makita HR 2470 FT (Japan/China) | 2,7 | 2,8 | 0,78 |
| 10 000 | 24 | Sold as an expensive tool for professionals. But the device cannot break walls. |
Drill a dozen holes for the dowel in concrete slab? Yes, this can be done with an impact drill - spending a lot of effort, time and not forgetting to constantly cool the drill. Or you can take a hammer drill and spend about three minutes on everything.
And if you need not a dozen holes, but more; you need to run a groove along the wall (a groove for hidden cable routing) or install a socket box in the wall - you can’t do without a hammer drill.
Perforator device
Why, with similar power, is a hammer drill incomparably more productive than a drill when drilling concrete? The reason lies in the design of the impact mechanism.
Hammer drills use two types of impact mechanisms, but both of them have one main difference from the impact mechanism of a drill: they have a massive firing pin that periodically strikes the chuck. Therefore, when drilling with a hammer drill, you do not need to apply any special force to the tool. On the contrary, if you do not press the hammer drill too hard, the drilling is even more efficient, because the chuck stroke is longer.
The pneumatic impact mechanism is used on powerful hammer drills, usually with a vertical engine. However, on some models with a pneumatic mechanism, the engine is located horizontally.
The mechanism allows you to create a large amplitude of movement of the piston, which increases the impact force.
The pumping bearing mechanism is used in compact rotary hammers with a horizontal engine. The mechanism is simpler and cheaper, but the range of movement of the piston is limited, and the impact is weaker. But the swing bearing is capable of providing a high (up to 7500 beats/min) impact frequency.
In most drills, the impact mechanism is implemented using a pair of ratchet gears. The tool itself serves as the striker, so the stronger the drill is pressed against the concrete, the more powerful the blow and the higher the productivity. But similar characteristics of a rotary hammer will still be several times higher.
Characteristics of rotary hammers
Maximum impact energy– the main characteristic of rotary hammers, which determines its capabilities and performance. The greater the impact energy, the larger the drill or bit that can be used and the faster the chiselling will occur.
For home use– drilling holes for dowels and anchor bolts– a light, low-power hammer drill with an impact energy of 1-2 J will be sufficient.
If the hammer drill is planned to be used for chiseling holes and installing socket boxes, more impact energy will be required: 2.5 - 3.5 J.
For drilling through holes of large length and diameter; for cutting passages in brick walls You will need a fairly powerful tool with an impact force of 4-10 J.
A maximum impact force of 10-30 J is required when dismantling walls and making passages in load-bearing concrete walls.
After selection the required strength impact, attention should be paid to power– it must correspond to the impact energy:
- for a maximum impact energy of 1.5 J, the optimal power will be 600 W;
- 2-2.5 J – 700-800 W;
- 3.5 J – 900 W
- 5-15 J – 1200-1500 W
- from 10 J – 1500 and above W
If the power is much lower than optimal, this does not mean that the manufacturer is trying to mislead you and the impact force is overestimated. Low-speed rotary hammers with a pneumatic impact mechanism can have high impact force with relatively little power. The capabilities of such rotary hammers will be the same as those of more powerful ones, but the productivity will be lower.
Impact frequency also affects performance. The more maximum number of hits per minute, the faster the hole will be drilled. High impact frequency (3500-7500 beats/min) allows low-power hammer drills with low impact force to have acceptable performance. Conversely, hammer drills with high impact force do not need high frequencies; they produce 2000-3500 beats/min.
Drill mounting type(cartridge). The most common options are SDS-Max and SDS-Plus.
Patron SDS-Plus Most low- and medium-power rotary hammers are equipped. The shank diameter of the SDS-Plus equipment is 10 mm, this is enough for drills with a diameter of up to 30 mm, chisels for scouring and crowns for socket boxes.
Cartridge SDS-Max designed for a shank with a diameter of 18 mm; powerful hammer drills are equipped with this chuck. Large diameter long drills, demolition bits and large diameter core bits have an SDS-Max shank.
Cartridge SDS-Quick Only used in Bosch compact rotary hammers. The shank of the equipment has a diameter of 8 mm, the maximum diameter of drills for concrete with such a shank is 10 mm.
Operating modes.
In mode chiselling the cartridge makes only reciprocating movements. The presence of this mode is necessary for chipping and cutting holes with a flat chisel. Drilling, especially deep holes, in this mode is not recommended; this will most likely lead to jamming of the drill.
Mode hammer drilling used for drilling holes in concrete, porcelain stoneware, cast and natural stone. For household hammer drills, this is the most popular mode.
Mode drilling(non-impact) may be needed to make holes in brick, cinder block or aerated concrete - in such materials, drilling with an impact may break the hole. The presence of this mode on a tool with a replaceable chuck allows you to replace the chuck with a cam one and use the hammer drill as a drill.
Using an adapter from SDS to a jaw chuck for the same purpose is hardly justified - the SDS connection allows significant play, the adapter with the drill will dangle, good quality drilling will not be possible. Therefore, if you plan to use a hammer drill as a drill, you should choose a tool with a quick chuck replacement system and an additional quick-release chuck included.
Some models are equipped with a screwdriver mode - it is similar to the drilling mode, but with a low rotation speed of the chuck. In this mode, you can tighten large-diameter screws. But hammer drills are not equipped with reverse and release clutch (ratchet), so you won’t get a full-fledged screwdriver. The weight and dimensions of the hammer drill are also not conducive to such use.
Some models have a Vario-Lock position on the mode switch - in this switch position, by turning the chuck manually, you can set the required position of the chisel for subsequent operation in chiselling mode.
Powering the device. The motor of a rotary hammer consumes high current, so for a long time rotary hammers remained exclusively networked tools powered by a 220 V network. But the development of technology and the creation of batteries capable of delivering high discharge current for a long time allowed the production of cordless rotary hammers to begin. Despite the heavy weight, high price and low impact energy, such a tool immediately gained great popularity - because in the absence of power supply it is much easier to use a cordless hammer drill than to carry a gasoline generator with you. Unfortunately, the operating time of rotary hammers on a single battery is still low - 1-1.5 hours at optimal load. As the load increases, the operating time can be reduced several times.
Maximum idle speed has virtually no effect on the speed of concrete drilling in the chiselling and impact drilling modes. You should pay attention to this parameter if the hammer drill is intended to be used as a drill - to confidently drill metals, you need a high idle speed (from 1200 and above).
Maximum drilling diameter. For ease of selection, many manufacturers provide maximum drilling diameters for wood, metal and concrete. But the drilling depth is not indicated, so these characteristics should be used with caution. For example, some 700-watt rotary hammers have a maximum concrete drilling diameter of 30 mm. Yes, you can drill a 30 mm hole several centimeters deep with such a hammer drill, but you shouldn’t expect to make a through hole in a concrete wall.
Functions reverse allows you to change the direction of rotation of the chuck and can be very useful when the drill jams. In addition, the use of reverse significantly facilitates the removal of long drills from holes. In screwdriver mode, the presence of reverse will increase the practicality of the tool and will allow you not only to tighten screws, but also to unscrew them.
Safety clutch prevents the tool from jerking when the drill or bit jams. This option is especially important for powerful hammer drills - in the case of a wedge in hammer drilling mode, without a safety clutch, such a tool is simply impossible to hold in your hands.
A hammer drill is a unique tool; no repair or construction can be done without it. There are a lot of recommendations on how to choose the right hammer drill for your home or work, but we have collected the most useful ones for you.
Builders and amateur craftsmen willingly share their experience of using various models, reveal professional secrets and talk about the fatal mistakes of poor choices. Analysis of numerous reviews on forums will help you decide which hammer drill to buy for home work or for a construction site, which models are suitable for highly specialized work, and which can be called universal.
What is better: a hammer drill or an impact drill?
When deciding to purchase a new tool, many people wonder what is more rational to buy: a hammer drill or an impact drill. There is no universal answer to this question, because everything directly depends on the characteristics of the upcoming work.
These two tools are capable of performing the same function - drilling concrete or brick, but structurally they have little in common. Mechanism impact drill will not provide performance equal to a rotary hammer, even if its power consumption is close to 1 kW.
The principle of operation of the impact mechanism is no less significant; if a hammer drill (in most cases) is pneumatic, then in a drill everything is arranged somewhat differently: the gears slip relative to each other. When regularly drilling hard materials, the low power of the drill adds methodical, natural wear of parts.
An impact drill, having a low weight and dimensions, is used for drilling products made of metal, wood, plastic, ceramics or other soft materials. Unlike a hammer drill, a drill can make neat holes of very small diameter. This is a convenient and practical tool that can be rationally used for drilling concrete or brick only “on occasion,” when you need to hang a shelf or curtain.
The hammer drill, in turn, is designed for working on concrete, here is an approximate list of tasks when you need to purchase such a tool:
- Installation of windows, doors, baseboards, suspended ceilings.
- Electrical installation work - forming grooves for laying cables, drilling holes for sockets.
- Fastening furniture or equipment to the wall (when the work is regular).
- Chipping old tiles.
- Creating window or door openings.
- Removing (chipping) excess concrete, demolishing the old foundation.
When installing the appropriate equipment, the hammer drill can easily cope with drilling any other materials, but is more suitable for holes of medium and large diameter. A specific model is chosen for certain types of work; there are also relatively universal modifications for a wide range of actions.
Criteria for choosing the right hammer drill
The general criteria for a successful purchase are very similar to the rules for purchasing equipment in general. When thinking about which hammer drill is best to choose to solve your problems, you should pay attention to the brand and availability service center. For models made in China The choice of spare parts is relatively wide, but components for professional-level devices have practically no analogues. Even if the unit is designed for long-term operation, a service center is still needed, because over time the carbon brushes wear out and the gearbox needs to be lubricated periodically. You should also keep in mind that not every tool can be serviced independently due to its complex design.
There is an opinion that professional-grade equipment is a priori better than household equipment, but this is a big misconception. Models for amateurs have a shorter lifespan and are inferior in terms of functionality and electronics, but are capable of performing all types of work. Professional rotary hammers are designed for long, intensive use in different conditions, which can be expressed in increased protection from dust, the presence of control and monitoring electronics, high technical performance. When it comes to small volumes of work, the difference between professional and amateur equipment will be invisible.
An important criterion is the class of the tool. The user must correctly assess the upcoming volume and type of work; this will help determine a number of suitable models. If your own experience is not enough, you can turn to the knowledge of the masters; they will tell you how to choose a good hammer drill and not spend extra money.
General classification of rotary hammers and their purpose:
- Simple power impact tools will be useful for drilling into wood and metal, such as drilling through logs with screw drills. Work on concrete and brick should be limited to rare use.
- Lightweight with “pneumatic” – models with a horizontal engine and a power of no more than 700 W. Such hammer drills are suitable for renovating an apartment and laying utility lines, because they can easily drill concrete, brick, metal, and wood.
- Average. This category includes the most powerful horizontal models with high impact force and all “vertical” hammer drills with an SDS-Plus cartridge. A tool of this class is suitable for intensive use, including drilling and chiseling of load-bearing walls, where the concrete is very strong.
- Heavy. In terms of its parameters, this type of hammer drill is superior to all other models. They are distinguished by increased productivity and are used primarily for chiselling, for example, creating or expanding openings for doors or windows, and are used for demolishing old foundations. Technical feature this class – high parameters of power and impact force, large mass, chuck type SDS-Max.
If you are deciding which hammer drill to choose for concrete or brick, choose a model with pneumatic impact. It is impossible to visually determine the type of mechanism, and not every seller will give full advice. It’s easy to understand the issue: in models with a mechanical shock, vibration is felt at idle, and pneumatics produce a shock only under load, directly during drilling.
Types of rotary hammers: straight and vertical
Structurally, all rotary hammers are divided into two large groups:
- Horizontal or straight.
- With a vertical engine or L-shaped.
Models horizontal type are presented in a wide variety of modifications; the power of such tools does not exceed 1 kW. They have compact dimensions and low weight. If you want to choose an inexpensive but good hammer drill, pay attention to models of this type, among them there are many successful versions at affordable prices.
Models with a vertical engine are more productive. Due to the special design of such tools, the level of vibration is reduced, a powerful electric motor is installed, and, accordingly, the mass is greater. Power consumption for different models varies from 900 W to 1.5 kW; as a rule, hammer drills up to 1 kW are household ones. When choosing such equipment, you should follow the operating rules, especially for amateur-grade power tools. The lower part of the engine, where the ventilation holes are located, is not always equipped with a dust protection system, resulting in a high likelihood of abrasive particles entering.
Impact energy and frequency
By the parameters of the hammer drill you can judge its capabilities. Impact frequency and force are key factors characterizing drilling performance and speed. Impact energy is measured in joules (J), for horizontal models the average is 1.5-2.7 J, the limit value for tools of this class is 3.2 J. More powerful vertical hammer drills with an SDS-Plus cartridge have an average impact force of 3 up to 7 J, and in productive and heavy SDS-Max the parameter reaches 12.5 J.
The impact frequency of horizontal devices rarely exceeds 4000 beats/min, but there are professional models where the figure reaches 4300 beats/min, like the Hitachi DH26PC. The limit value is 5,800 beats/min for the Bosch PBH 2000 RE household hammer drill. For minor repairs in an apartment or country house, this indicator does not play a decisive role, but it is worth paying attention to; the value should not be too low. Modifications with an L-shaped engine, designed more for chiselling, the impact frequency of such devices is slightly lower - about 3600 beats/min (Bosch GBH 4-32 DFR-S).
Summary: impact force is especially important during intensive chiselling; the higher the indicator, the more efficiently the tool will cope with the assigned tasks. The impact frequency determines the drilling speed.
How to choose the power of a hammer drill
Rotary hammers are chosen exclusively based on power among models of the same class. This indicator is not the main factor when purchasing, what is more important is the ratio of this value with such characteristics as force and frequency of impact. As the experience of craftsmen shows, a power difference of 650 - 750 W is not critical if we are not talking about drilling load-bearing walls or foundations.
Among the recommendations on how to choose a hammer drill for your home, experts do not highlight a specific range. Modifications with power up to 700-720 W will cover all household needs. For construction, overhaul or redevelopment, you should choose between horizontal models (average 800 W) or heavy chiselling models (1.1-1.2 kW or higher).
Shaft speed
The number of revolutions of a hammer drill has a certain importance when performing specific work, but by and large this parameter does not play a significant role, especially when choosing an amateur-class tool.
Craftsmen who are professionally involved in repairs or construction recommend choosing models with high rotation speeds for producing small-diameter holes or for working with thin walls and thin beams. If the task is to drill thick monolithic walls or logs, high speed will unnecessarily overheat the equipment, which will somewhat accelerate its wear.
Drill mounting type
Another important thing is to divide rotary hammer models into groups - by type of equipment or type of drill attachment. Today there are two main modifications: SDS-Plus and SDS-Max, and the equipment is grouped similarly.
Ammo SDS-Plus installed on all light and medium models, as well as on household and low-power devices with a vertical engine. The equipment includes drills with a diameter of up to 32 mm, picks, and a chisel with a similar fit.
Rotary hammers with fastening type SDS-Max– these are always powerful models with a vertical engine and high impact force. The equipment for such tools starts from 12-14 mm in diameter and reaches 52 mm, the length of the drill varies from 310 mm to 1 m. The difference between the consumables for a tool of this class is a wide fit and 4 victorious solders at the drill site, for SDS-Plus soldering is usually 2.
Unlike a drill, a hammer drill chuck is almost always built-in, like the Makita HR 2450; to use conventional drills with a cylindrical shank, a special adapter from SDS-Plus is installed on a regular drill chuck. Among the offers from the best manufacturers of hammer drills there are modifications with a replaceable chuck - Makita HR 2450 FT, here the standard drill chuck can be removed and a special chuck for drills can be installed. Naturally, this is more convenient than a combination of an adapter and a second cartridge, but the additional accessory increases the final cost of the tool by a third.
Owners of models with the SDS-Max mounting type can choose an adapter for installing SDS-Plus cartridges. There are no replacement chucks available for conventional drills with a cylindrical shank.
Power type
Choosing good model for home or work, the user must decide on the type of power supply: mains or battery. With network hammer drills everything is very clear, the unit is connected to an outlet or extension cord, respectively, if there is no electricity, the tool will not work.
When thinking about buying a cordless hammer drill, you should know about all the features of this equipment:
- Operating time is limited by battery capacity.
- Between the built-in and replaceable battery, you should choose the second option. It's even better if the battery type is Li-Ion - they are much lighter than Ni-Cd.
- Cordless models are very convenient when working on a roof, in a country house or in a garage without electricity, but in terms of power they are several times inferior to networked rotary hammers.
- The purchase will be rational in conjunction with a network tool. The mobile model helps out when connecting to the network is impossible or requires a lot of preparation, and the amount of work is small.
Number of operating modes
Depending on the modification, this power tool may have 2, 3 or 4 operating modes:
- drilling;
- hammer drilling;
- chiselling;
- rotation of the equipment (used to install the blade in a comfortable position).
Dual-mode rotary hammers– these are tools for a narrow specialization; there are models that combine drilling/drilling with impact or drilling with impact/chiseling. Such models are purchased for a specific range of tasks or in conjunction with another tool.
Tri-mode– universal models for wide purposes. If you need a tool for various jobs around the house, this is the best hammer drill among its analogues. The fourth mode with rotation of the blade is convenient, but in practice this function is not critical; you can choose a comfortable position in the drilling mode.
The mode setting method for models with a horizontal engine is always the same– a round regulator in the upper or lower part of the body. For “vertical” ones, switching is of two types: similar to “horizontal” ones or in the form of two separate regulators. In practice, there is no significant difference between them; the user can choose what is more convenient for him.
Features that may be useful
When assessing the functionality of a rotary hammer, you should know about the basic options. Often sellers talk about them as unique feature, but in practice this is just minimal technical equipment. Such possibilities include reverse; its absence is rather an exception to the rule. The reverse stroke will help remove the equipment if it is jammed in the material. Here it is worth paying attention to the type of switch; it is good if it is located on a separate key and not located at the start button, similar to an impact drill.
Fixing the tool in the on position and a mechanical protection button are the usual basic options.
If the task is to choose a reliable hammer drill for work, you should pay attention to the presence of additional functions:
- A safety clutch or KickBack Control technology is a useful safety option. When the equipment jams, the electronics blocks the engine, protecting the operator from inertial shock.
- Automatic shutdown when the carbon brushes wear out will help protect the tool from damage.
- A vibration damping system, like the GBH 2-24 Professional model, is found mainly in professional rotary hammers. This option is very useful - it protects your hands during regular, long-term drilling.
- A smooth start when drilling reduces the load on internal mechanisms; this feature is most often found in powerful models.
In professional equipment of the highest price segment, there may be other options, for example, a dust removal system, like some Makita rotary hammers. These are no less useful technologies that significantly increase the final price of the unit. How rational the overpayment will be depends on the type and conditions of the work.
Compliance with operating rules is the key to long years of tool service, and this applies to all models. First of all, you need to study the user manual, where there is always a general list of requirements.
It is important to know that the continuous operation time is never indicated; for a household-class tool, the limit is 4-6 hours a day with regular breaks. Professional models can work for 8-12 hours with rare stops and are superior in reliability to amateur hammer drills.
The most common cause of breakdowns is the ingress of concrete or brick dust or abrasive particles into the housing. This happens in three cases: if you do not clean the tool after work, if you work in a very dusty room with household tools, or if you place the hammer drill on a dusty floor until the engine stops completely (a frequent breakdown in models with a vertical engine).
The result is non-warranty repairs and replacement of major parts, avoid similar breakdowns Regular cleaning of the instrument will help. It is useful to carry out routine maintenance of the tool at an authorized service center, where a technician will open the hammer drill, lubricate the gearbox, check the condition of the carbon brushes, and remove dust.
Which company should I choose a hammer drill?
The number of manufacturers of such a popular tool as a hammer drill amounts to hundreds of brands. It is best to give preference to one of the leaders in your industry, because the concept of “brand” means not only increased cost, but also its own developments and technologies, proven designs, and rich experience of engineers. Among the popular manufacturers of high-quality rotary hammers in the price-quality ratio, the following stand out:
- Bosch
- Makita
- DeWalt
- Interskol
- Metabo
Bottom line
In order for the purchase to be successful, you should clearly understand why a new tool is needed, what tasks may arise during the repair or construction process. Much has been said about how to choose a hammer drill yourself and which model is best for home or work, but in conclusion you can add one more helpful advice from professionals - purchase only the model that fits comfortably in your hands. The right combination of technical characteristics and decent ergonomics will be the key to productive work and long term tool services.
A hammer drill is a tool that you cannot do without when performing construction work. Such work also includes repairs at home, in which a hammer drill is used quite often.
Therefore, when performing home repairs, you will need to choose the right tool.
How to choose a hammer drill for home work?
Rotary hammers are divided into professional and household. The main differences between these categories are the time of uninterrupted operation before overheating and the time of operation without interruption. U professional models these parameters are much higher.
A household hammer drill is also suitable for use at home. In most cases, such structures do not a large number of additional functions, rotary hammers are lightweight and much easier to operate and maintain. These devices are not very expensive when compared with professional rotary hammers.
An important parameter of this design is weight. It is quite difficult to work with a heavy device. By weight, rotary hammers can be divided into the following categories:
- Lightweight device. The weight of this hammer drill is less than 4 kg.
- Medium weight tool. The weight of this design ranges from 5 to 8 kg.
- Heavy weight device. This device weighs more than 8 kg.
Devices of the first two categories are in most cases used for drilling holes of small diameter and shallow depth. A device of the third category can even be used as a jackhammer.
The switch stopper is an element that must be on the hammer drill. It is a special button that can secure the switch in a certain mode, without the need to constantly hold the switch with your fingers. This feature will be especially useful during long periods of drilling holes in hard materials. In this case, your hands will not get too tired, therefore, you will need to take fewer breaks while working.
Depending on the location of the engine, there are 2 main types of hammer drills in the housing: horizontal and vertical. In a horizontal type device, the electric motor is placed parallel to the impact axis. Such designs are used for working in narrow openings. In device vertical type the engine is located perpendicular to the impact axis. IN in this case the motor cools faster.
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Operating modes and power
A large number of household appliances have several operating modes. The main function is impact drilling. All models have it. Some devices can also operate in the mode of an ordinary drill and chisel function.
All rotary hammers for home use are equipped with standard commutator motors, which is why power is the most important among all design parameters. The performance of the tool will depend on the power on the shaft, and the power used does not matter. In most cases, this parameter is indicated in the passport of the electric tool.
Knowing the approximate efficiency of a standard engine, as well as friction losses in the hammer gearbox, you can approximately determine the power on the shaft of the device, taking into account exclusively the power used, which is indicated in the passport.
Consequently, engine losses by high voltage(maximum possible shaft speeds for designs without a gear design or high shaft speeds for high speed for devices with multiple speeds) can be taken as 30%. For home needs, you can use rotary hammers that have a shaft power of less than 500 W.
The maximum usable power for a home hammer without a gear design will be approximately 714 W (500*100/(100-30)). For home devices with a mechanical device of this type, the maximum power used will be approximately 735 W (500 * 100 / (100-30-2).
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Number of revolutions and strokes
For high-quality impact drilling (the main function) you will not need high speed rotation of the shaft, which is why most often builders prefer devices with low speeds (less than 1000 rpm).
High speeds will be needed if you plan to use additional functions. In this case, the hammer drill will be used as a tool with many functions. There may be the following approaches:
- Multi-speed device with mechanical gear design.
- Purchasing an external gear design for a hammer drill that operates at one speed.
- Selecting a device with high speed and high power usage.
You should not focus on the number of blows, since everything modern models devices in the chiselling and impact drilling functions can produce a minimum of 2500-3000 blows/min. It is worth noting that this amount in the house will be quite enough. If a large number of blows are necessary, then best choice there will be professional tools.
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Impact energy and multi-speed capability
Impact energy is an important parameter. It can be used to determine the efficiency and productivity of working with high-density construction materials (for example, concrete). Average values are in the range of 2-4 J. In professional devices this figure is high. For infrequent work with low productivity, an electric drill may be sufficient.
In standard models of devices of this type, this indicator is in most cases not adjustable, so it will not be possible to change it during operation.
If you plan to work for a large amount of time in impact drilling mode, then you should purchase a hammer drill with low shaft speeds of an electric motor whose power is less than 1 kW.
The use of a mechanical gear design built into the rotary hammer body allows it to be used as a multifunctional tool. The main disadvantages of such a gear design are: high level noise, relatively high cost, heavy weight, considerable size, the need for additional maintenance of the gearbox, a high probability of breakdown of the gearbox structure and the entire tool.
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Maximum diameter and protection coupling
In most cases, the drilling diameter is indicated in the specifications of the hammer drill. In order to drill wood and steel, you will need to use a drill bit attachment, which most often comes with a hammer drill. The nozzle is installed in a special cartridge. If you are using a hammer drill for your home, then it must be equipped with an SDSplus type chuck. Consequently, the maximum diameter of the hole during the drilling process will depend on the parameter of the nozzle and chuck.
However, the main purpose of such a tool is to work with concrete. For concrete, the most common hole diameters are 14-26 mm, which is quite sufficient. If you plan to perform other work, then you should pay attention not to the maximum drilling diameter, but to the weight and dimensions of the purchased device, since holes of any diameter are most convenient to drill when using small-sized perforator structures.
The least important parameter is the safety clutch, since the likelihood of injury to hands in the process of jamming the drill is negligible when using the tool at home, due to the fact that in this case there is a low torque of the electric motor shaft. In devices where there is a large torque (professional devices), most often a safety clutch is included with the device.
