When repairs are underway or a house is being built, a hammer drill is one of the most needed tools. With the advent of this device, capable of withstanding significant loads, it became easier and more comfortable to work. The choice of such devices is huge today - they are offered by each manufacturer of the tool.
But how to choose a hammer drill, which will be of high quality, convenient and will last a long time. Such a question is quite justified - after all, you will have to spend a considerable amount on the purchase - this pleasure cannot be called too cheap. To make the right choice, you need to know the principle of operation of the punch and the features of its design. Consider all this in detail to find out how the different models of such devices differ from each other.
Content:
Impact drill and punch - not the same thing
Some mistakenly believe that a hammer drill works just like a hammer drill. But this is not so - although they call such a drill a “drill-puncher,” the principle of operation of these two electric tools is strikingly different. Yes, they both punch holes, but blows at the same time have different strengths, as well as different origins.
A percussion-type drill works as a punch due to the gearing of two wheels, called rattles. At a certain pressure on the drill, an oscillatory movement of its axis occurs, which allows you to make a hole. But productivity cannot be high, and the hits are pretty weak. Therefore, solid concrete, for example, cannot be punched with such a drill.
But the punch is just designed for drilling stone, brick and concrete. It can also be used to transfer force to the working edge of peaks, blades or drills, allowing these tools to work with maximum efficiency.
In the puncher, the mechanism of an electromechanical or electro-pneumatic type is used as the main structural element. Thanks to it, an impact force is created that is sufficient for punching concrete or stone. In this case, the master does not need to press hard on the handle of the punch. In some models, the mechanical impact mechanism is similar to that of a drill, but it is less durable than the electromagnetic or pneumatic mechanism.
The piston and the mechanism of the pneumatic impact system, as a rule, are equipped with L-shaped perforators.
A mechanism like a drunk bearing, which rotates the striker to strike, is equipped with narrow punchers.
So, if you compare the mechanical and pneumatic mechanisms, you can see that the latter greatly facilitates the work on a hard surface. When using a mechanical percussion device, it is necessary to exert a force three times greater than when using a pneumatic device. Therefore, when deciding how to choose a hammer drill for your home, it is better to look in the direction of more modern models, and forget about mechanical ones safely.
- See the material >> The difference between a punch and a percussion drill - let's put everything on the shelves
What to consider when choosing a hammer drill
This tool can be: with one drilling mode, with two modes (drilling plus impact), as well as with three modes (slotting is added to the previous two modes). In addition, perforators are classified by weight into heavy, medium weight and light. The latter will be no heavier than 4 kilograms, medium ones will “pull” from 4 to 5 kilograms, and the heaviest devices of this type can weigh 5-10 kilograms or more.
Impact energy
One of the main parameters of the device is the impact energy. Joules are used to measure it. Light models have a blow force of no more than 1-2 joules, and punching machines that are “more serious" can hit with a force of 8 to 15 joules. The greater the impact energy, the larger the diameter of the hole can be obtained. When this value is small enough, the device does not work more efficiently than a hammer drill. At the same time, he will not punch a hole, but drill it. As a result, his equipment will wear out extremely quickly, and you will not have to dream of high performance.
Speaking of impact energy, one must know that it does not depend on the force with which to press on the handle of the punch. But when working with an impact drill, the situation is just the opposite. If the entrepreneurial shop assistant tool for attracting attention talks about the increased impact energy of a hammer drill, listen to his words skeptically. You should be aware that a value of this parameter exceeding 10 joules will lead to a quick failure of your tool. Indeed, at such high loads, its refractory inserts will collapse in a very short period of time.
Beat frequency
If we calculate how many times in one minute the piston of the device hits its firing pin, we get a value called the frequency of the blows. The larger it is, the higher the hole punching speed. The performance of a punch depends on both frequency and impact energy. Manufacturers that produce the most durable and efficient devices in their models harmoniously combine these two parameters. Therefore, when thinking about which puncher to choose, it is better to pay attention to reliable brands whose products are of excellent quality and amazing durability. Specifically, about the best manufacturing companies, we will talk a little further.
Punch Power
Hammers are less powerful devices than electric drills. This is because drilling is much harder than drilling. Therefore, the shaft of the punch during operation does not require such a high speed of rotation as that of a drill. For devices with different types of cartridges, the power is different. From 400 to 800 watts, models with cartridges of the SDS-Plus type consume. Hammers with SDS-Max cartridges have a power ranging from 1 to 1.2 kilowatts. As a matter of fact, when choosing this tool, emphasis should not be placed on power - this is not the most important parameter.
Spindle speed
The rotational speed of the rotary hammer shaft is lower than that of a drill - this is already mentioned above. Depending on the class of the device, the value of this value can be from 600 to 1500 revolutions per minute. The rotational speed decreases with increasing power and productivity of the punch - this is due to its design features. Indeed, in production models, the optimal tooling diameter is quite large. In general, the shaft of the device rotates only in order to remove dust after drilling. A small boer has to rotate faster, and a large bora slower, otherwise it will wear out too quickly.
Models of rotary hammers with a high shaft rotation speed have considerable weight, which does not facilitate ease of use. In addition, in such high-speed devices, spiral grooves wear out very quickly, with the help of which drilling waste is removed from the workplace. Because of this, the device begins to heat up quite strongly, and as a result, it can even jam in the hole.
Type of drill holder
When discussing with friends and acquaintances which punch is better, the home master does not always take into account one important parameter. This is a way to fix the drill, which at the moment there are three.
If you need a small device weighing up to 4 kilograms, it is better to choose a model with an SDS plus mounting system. Such a device can make holes with a diameter of not more than 3 centimeters. Usually this is enough for domestic needs, and such drills are most in demand by customers.
Professional models, sometimes weighing up to 11 kilograms, are equipped with SDS max. These devices are quite large. However, they are capable of breaking holes rather big - up to 5.2 centimeters.
Two types of mounting, SDS Plus on the left, SDS Max on the right.
Recently, another type of mount has been used - SDS-top. It is well suited for making holes with diameters of 1.6 to 2.5 centimeters. This mount is often used in devices manufactured by Bosch.
Punch modes
Now let’s take a closer look at how punchers with a different number of operating modes differ from each other. So:
The simplest devices are single-mode. They work the same way as an ordinary drill. If you have to drill wood and metal surfaces, then they are quite suitable.
In a dual-mode device, the axis is able not only to rotate, but also to perform oscillatory movements during rotation.
The three-mode rotary hammer as an additional function has the ability to strike without spindle rotation. Such a device is the most versatile, it can simply drill, drill and hammer and just hammer.
The variety of models of rotary hammers suggests that each of them can have different modifications. Moreover, they can be performed with either one, with two or three modes of operation. If we talk about the latter option, then it costs more, of course. But such a device will help out a lot, if you have to choose a punch for work both in drilling and in drilling and crushing, then you definitely need to stop at a three-mode device.
When choosing a device, its shape and design play an important role. Holding the device in your hand, you need to feel that it will be convenient to work with it. At the same time, pay attention to whether there are side handles that can be easily removed - excellent, if such an option is provided. It will help if you have to drill in a tight corner, for example. He took off the pens - and work with all the amenities.
Punch shape
In the form of perforators are both straight and L-type. In the latter, the engine is located vertically, making the device more compact. In addition, engine cooling is quite efficient. Such devices can work for a long time, without overheating, and they serve a lot. That's just the weight they have very tangible.
L - shaped punch, the engine is located vertically.
Narrow and long straight-type perforators weigh less, and due to their design they will crawl into any slot. The engine in them is placed horizontally.
A narrow, long hammer drill, the engine is horizontal.
The following functions can be integrated into the rotary hammer:
- The depth gauge will help you know if the drill has reached the desired mark.
- The gearshift mechanism is useful when you need to switch from a drill to a drill or vice versa. After all, they must move at different speeds.
- Reverse rotation of the shaft will help out when the drill gets stuck in any surface.
- Soft start and a device that protects against overheating will help to avoid troubles that promise a breakdown of the device.
- Stabilization of the shaft speed during fluctuations in the load force is a very useful function.
Additional functions
Thinking about how to choose a good hammer drill, we hope that it will contain all sorts of convenient additions.
1. So, for example, protection from dust does not hurt at all - after all, hardly anyone has to work in sterile conditions.
The device for protection against dust during drilling.
2. No less convenient is the anti-vibration system, which softens and compensates for the shaking of the device during drilling, chiselling or drilling.
Vibration protection system.
3. Another useful “trick” is a locking button that secures the punch in operating mode.
True, each of the additional features does not cheapen the device at all, so choose only what you really need.It’s not worth, right, to overpay for those functions that you will never use in the future.
Punch Options
And now let's talk about the configuration of the punch - the more complete it is, the less tools will have to be bought later. So, what should be in the case with the device:
1. Spare brushes for electric motor.
2. A special chuck, which is an adapter, will help to use ordinary drills for drills, rather than quick-clamping drills. After all, punch drills are more expensive, and in the absence of such a cartridge will have to spend pretty much.
3. Drills - the main set. For domestic needs, it will be more than enough, but professional models need a more impressive set.
Manufacturing firm
Now let's talk a little about which company to choose a hammer drill. The most reliable brands that almost everyone has probably heard of are BOSCH and MAKITA. It is in their direction that you need to fix your gaze, choosing a professional model of a hammer drill. And for the house, in addition to these two companies, you can also advise the following manufacturing companies WATT, STERN, EINHELL, VT.
And yet: a domestic model or a professional?
More expensive and powerful professional appliances come with many features. They are reliable and durable. It is easy to distinguish them: as a rule, for all manufacturers, models for professional use are painted in a different color than household ones. And the inscriptions corresponding to them are available. But the most important difference between them is the time of continuous work, which lasts 7-8 hours, that is, the whole working day. However, why is a heavy and bulky device for the “pros” at home? As a rule, it is not necessary to carry out super-tasks, and for the most ordinary repair or hanging of shelves, a middle class model is quite enough.
Let's list the optimal characteristics of the punch, which is planned to be used for home use. With these parameters, you can easily and quickly drill holes in concrete with a diameter of 1.6 to 2.8 centimeters, as well as perform other types of work. So, a good hammer drill has the following parameters:
- Power - from 0.5 to 0.9 kilowatts.
- Impact force - from 1.2 to 2.2 joules.
- There are three operating modes (except for drilling, also chiselling and drilling).
- Adjustment of shaft rotation speed.
- There must be a protective coupling - it will protect the device from jamming.
- The drill must be secured with the SDS plus system - you do not need to use keys to clamp or expand the cartridge.
Then see for yourself - hold the tool in your hands, try to make a test hole. If you feel that it will be convenient to work, take it. In general, the answer to the question of which punch is best to choose is obvious. Of course, the one that will be most suitable for your tasks. Just keep in mind that when performing these tasks, the device must be handled carefully. More about this below.
We operate the rotary hammer correctly
These few simple rules will help your lovingly chosen tool last a long time, avoiding annoying breakdowns.
So:
- It is advisable to use only "native" cartridges, drills and lubricants that are provided by the manufacturer.
- Maintenance, cleaning and lubrication are recommended regularly. Pay particular attention to the lubrication of the SDS tool shank for operation.
- Do not use the device for a long time without stopping. It is necessary to periodically give him time to cool.
- When drilling a deep hole, the work must be done in several steps, each time pulling out the drill and thereby cleaning the hole. This will happen due to the removal of drilling waste.
- If you press on the tool, then the shock mechanism will wear out ahead of time. Also, this is fraught with overheating of the engine armature.
- Use the chiselling mode for a short time - mix it in a rotational mode, at least for 2 minutes. This will allow the device to cool, and also allow the grease to evenly distribute to the desired places. Thus, the forced lubrication system will work.
- In order not to break the cartridge, it is necessary to work strictly perpendicular to the axis of the punched hole, avoiding distortions of the tool.
- The boot and brushes of the electric motor should be inspected periodically, putting in order and replacing if necessary.
- Do not wait until a small malfunction turns into a major breakdown. It is better to immediately contact a service center - it will be much cheaper.
Thus, we believe that you received the answer to the question of how to choose a puncher correctly.
Video: Punch Selection
