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-cutters, 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.

The GSH 5 E bump stop immediately impressed with its impact force, which reached 12 J at a possible frequency of 3000 bpm, which at that time was 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 in the next apartment to collapse. 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 with ease.

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 triggered by the constant electronics, which does not allow the engine speed to drop. Service display helps monitor tool status.

The BOSCH GSH 5 E demolition hammer is very convenient for working in a horizontal plane, on 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 comes with a very convenient bracket-shaped additional handle. It is bent at an angle, which allows not only to turn it 360 °, but also to narrow or expand the grip. The start key is large, it feels well even in rough gloves. All switches work clearly and easily.

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 well insulated. Another nice “Bosch” know-how is the articulated connection of the cable to the bumper body. Movable sphere prevents cord breakage, especially useful for pinched spots.

The flat spade can be rotated to one of 12 positions for precise, comfortable chiselling in confined spaces. Bosch’s developers have named this system “Vario-Lock”, which is successfully used on all of their rock drills and fenders. 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, indicates the power of the tool, the massiveness of the parts. For example, BOSCH 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 to continuously operate the tool, use 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 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 specific 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 motion, 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 force of the blow and the number of blows per unit of time are the main indicators of performance, but a lot 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 shock 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).

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..

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%. Added to this are handles with spring suspension and damper inserts, rubberized and foam pads. For example, HILTI has proposed an Active Vibration Absorption (AVR) system – the TE 1000-AVR or TE 3000-AVR (68 J) models..

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 strong and durable. 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).

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..

Let’s sum up

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 public knowledge, 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 the “branded” one. 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..