Electric trowel for concrete – Trowels – buy a helicopter for concrete

February 4, 2020 Concrete, brick, facade materials

Concrete floors and screeds had been poured before, but their “quality” began to manifest itself almost immediately. The uneven structure and porosity led to the fact that the concrete began to crumble and dust, absorb liquids and finally collapse.

Attempts to strengthen the surface layer using the ironing method, rubbing dry cement into wet concrete, were successful only in limited areas. How many kV. meters can be rubbed with a trowel?

With the use of trowels, hardening of concrete surfaces has become widespread not only in industrial enterprises, but also in civil engineering. Trowels of various types and sizes allow you to process floors in both small rooms and large areas, without access to electricity and in cramped conditions.

Where is floor hardening used?

You can treat floors with a trowel in any room. This will increase its strength, water resistance, and reduce dust formation. You can use concrete of a lower grade - this reduces its cost. When machine processing the screed, preparation for laying the floor covering can be considered complete - no additional leveling is required.

It is not necessary to use all the technology for strengthening floors in apartments. The concrete is still covered by the floor covering and is not subject to mechanical stress.

Another thing is warehouses, gyms, swimming pools, parking lots and production workshops. People not only drive, walk, and drag loads on such floors, but also spill various liquids – water, fuels and lubricants and other “chemicals.” Therefore, it is no longer possible to do without additional strengthening substances.

Rotor size

The grinding rotor comes in the form of blades or disks. The grinding speed directly depends on its size.

1. Blade knives. Diagonally, their size ranges from 30 cm (the smallest) to the largest - 120 cm. The larger they are, the more efficient the grouting. Small blades are needed in narrow passages and small rooms.
2. Disks. For electrical devices they do not exceed 980 mm. Inexpensive, they do an excellent job with simple tasks. The electric motor simply “will not pull out” a disk that is more than a meter in diameter - it will overheat and fail. Therefore, we recommend installing large wheels on gasoline models and using them to sand large areas.

Methods for strengthening concrete surfaces

Even simply machining concrete floors improves their performance. But with additives, concrete acquires new properties.

There are two technologies for hardening the concrete surface:

• Impregnation with special compounds that fill pores and strengthen the structure of the material.
• Adding dry substances to the surface layer - topping.

Video: Concrete trowel petrol masalta MT36-4

Chemical protection of concrete

To impregnate concrete floors, sealers are used - liquid hardeners that penetrate the concrete structure and create a durable surface layer. They do not form a film, so they are not subject to abrasion.

The composition is different: water-based, organic, and multi-component. Each has specific applications. It is usually applied in an even layer to the finished concrete, and after filling the pores and gelling, the residue is washed off with water.

Concrete topping

If sealers can be used to protect concrete of different “ages,” then the addition of dry substances is possible only under a certain state of the concrete mixture. In addition, compliance with all requirements for the composition of concrete and reinforcement and laying technologies in this case is mandatory.

• Concrete grade – not lower than M300.
• The thickness of the screed is at least 70 mm on a concrete base and 120 mm on a compacted surface.
• Reinforcement frame and compaction with vibrators during installation are required.
• It is also recommended to carry out work at a temperature not lower than +10°.

Types of topping differ in composition and, accordingly, in scope of application.

Quartz is the most common and inexpensive. In addition to quartz sand, dyes are added to the composition, which allows you to diversify the color range.

Corundum contains more durable corundum chips and has an attractive appearance.

Metallized topping is the most durable and its area of ​​application is the most severe conditions.

Video: Grost universal trowel

Consumption is determined by the requirements for floor strength and ranges from 3-5 to 12 kg per m2.

The main feature of the process is to correctly determine the time for adding topping. A few hours after laying (this depends on many factors), when the concrete has set to the point where the shoe footprint on its surface is no deeper than 3-5 mm, 2/3 of the powder is evenly distributed and the first grout is done.

Then the rest is added and after the “milk” is absorbed, it is mashed again. After waiting until the shoe print is barely visible (1 mm), the finishing grout is performed.

Then they are coated with a special varnish or other compounds. To prevent deformation of concrete floors due to temperature changes, expansion joints are cut at a certain pitch.

Strengthening of concrete is most often carried out in a comprehensive manner: both dry compactors and sealers are added. It is recommended to follow the instructions for use given by the manufacturers. Only then will the investment be worth it.

Surface type

Which grinder is best to choose is initially determined by the type of screed. For semi-dry, certain models are needed, and for dry, completely different ones, since it is tens of times harder.

1. A semi-dry screed is one that has not yet hardened. It is formed immediately after compaction with a vibrating lath. To level it, helicopter-type trowel grinders are used. The process is performed in two steps - rough grouting and finishing. For each of them, different nozzles are used. For rough grinding it is a disc, and for finishing grinding it is a blade knife.
2. Dry screed is already hardened cement. It is too tough for a bladed knife. Only diamond crowns or discs with a high content of diamond coating can handle this. In addition, the device must be able to connect an industrial vacuum cleaner and an irrigation system, since the dust “stands like a pillar.” Such machines are used for the restoration of old concrete pavements. Often mosaics or decorative floors containing granite and other natural stones are also polished with similar devices. Because they are even harder than concrete itself, the grinding bits are equipped with the toughest carbide diamond segments.

What do you use to grout concrete floors?

Even in small rooms, it is advisable to use mechanical means for grouting. For this purpose, trowels are produced in different types and sizes. The principle of their operation is simple: the engine rotates disks or blades, which “rub” the compactor into the upper layers of concrete. Due to their resemblance to an aircraft, they are often called "helicopters".

Trowels can be divided into several types:

Double rotor trowel

1. To size. Small “helicopters” have one disk and are designed for small volumes of work. The operator controls it using a handle bar on which the controls are located. Some models have a rotation speed controller. The blades of the machine are covered with a special fence for safety purposes. This casing and the diameter of the blades limit access to secluded areas of the room: corners, floor edges near walls, around columns remain untreated. To access them, edge “helicopters” or vibrating screeds are used. Twin-rotor machines have two rotating disks or two pairs of blades. The grip of such machines is much greater, which determines their use over areas of hundreds of meters. Such a “helicopter” is no longer dragged by the barbell. The operator sits on a special chair and controls its movements using control handles.
2. According to the type of engine used. Smaller machines often use an electric motor to rotate the blades. This is understandable. There is little movement, no long cord is needed. And a gasoline engine in a confined space with its exhausts does not add comfort to work. In addition, gasoline cars are much more expensive. Double-rotor trowels require freedom of movement. It is difficult to imagine a “helicopter” “tied” to an outlet in a room of several tens of kV. meters with columns. The gasoline engine allows you to perform any maneuvers, and combustion products are no longer so dangerous if the room is well ventilated. The advantages of a gasoline engine include higher power.

Gasoline power trowel

Principle of operation

The concrete grinder consists of three blocks:

1. Engine;
2. Control;
3. Grinding part.

Everything is clear with the engine. It creates torque and transmits it to the trowel block using a special gearbox. The cutting part is much more interesting. It is made in the form of a huge fan. Its blades are sharply sharpened knives. In some cases, this is a large grinding disc or even a diamond crown. The fan rotates, the blades (crowns or discs) scrape, cut, rub and smooth - in general, they do everything that is needed for a smooth coating. Moreover, their function depends on the inclination of the knives. A rough grout is needed - less slope. Gentle finishing sanding is expected - the blades lie almost parallel to the screed and gently smooth it.

All described farming needs to be effectively managed, which is done using the handle. It contains levers and buttons with which you can:

• perform Start-Stop;
• select the desired rotation speed;
• change the angle of the blades.

In addition to the main blocks, there are also additional ones. It is mandatory to install a casing to cover sharp elements. This is one of the safety standards. The casing is well thought out, it is lattice, so the view of the working area is not obstructed. The handles are equipped with rubber pads to prevent slipping. There are also optional elements. For example, an operator's chair with a control joystick or an irrigation system. As a rule, they are installed on the most powerful and expensive industrial-scale devices.

How to operate a trowel?

When working with a trowel using topping technology, it is important to follow some rules.

• Follow the rules for laying the concrete mixture. Reinforcement, sealing, grade M300 and more, without plasticizers.
• Only concrete that has set to a certain state is processed. They start when the shoe print is 3-5 mm.
• During the first pass of the disk machine, the top layer is leveled and compacted.
• The sealant is applied using a special dosing trolley. After absorbing the moisture, they go through the machine again. The direction of movement is changed after each pass.
• Apply the sealant again and continue grouting with the blades.
• Passages are made as the concrete mixture hardens at intervals of 0.5-1 hour.
• Do not forget to control the surface with a control rod.
• The completion of the work can be determined by the shiny surface.
• The final stages remain: applying varnish and cutting joints to a depth of 1/3 of the thickness of the concrete layer.

Video: Double-rotor trowel Wacker Neuson CRT 36-24A-E

Areas of application

In fact, the concrete trowel machine is used in two areas: construction and renovation. In both areas, its tasks are the same, except that they differ in the scale of the processes and their duration.

The equipment performs:

• leveling the concrete surface;
• Grouting the concrete before applying the reinforcing layer;
• reducing the amount of dust on concrete;
• grinding concrete to obtain a matte finish;
• smoothing of coarse aggregate;
• removal of depressions, tubercles and other minor defects.

Buy or rent?

Perhaps neither. The specific solution depends on the scale of the work.

If you decide to grout the screed in your apartment, then all you need to do is rent a small electric trowel. This will be enough for an apartment.

If you are building or renovating a warehouse, farm, or auto repair shop, you can buy a small “helicopter” and rent a larger car. It is also recommended to take a closer look at the prices of companies providing such services. Perhaps the issue will be resolved differently.

But if pouring floors is your business, then you need to buy all the equipment, from a compactor cart to a gas powered trowel, not to mention the tools for laying concrete.

Discussion: there is 1 comment

1. Basil:
   February 21, 2020 at 8:19 am

   When choosing a power trowel, it is better to choose Kreber. This manufacturer has a wide selection of reliable trowels suitable for both small and large construction sites.

   Login to reply

engine's type

The concrete machine can be gasoline or electric. Each has its own objective pros and cons.

1. When using gasoline, they are a priori more powerful and productive, and they are also completely autonomous. They are used in large open areas, as well as in new buildings where there is no connection to the power grid yet. Their disadvantages are troublesome maintenance, the need for refueling, dimensions and heavy weight.
2. Powered by an electric motor – light and maneuverable. But the power indicators are lower, and the range is limited by the network cable. There is no alternative to them in enclosed spaces.

Recommendations for use

To perfectly smooth a concrete floor or cement screed, you need to work in two stages:

1. The first is a rough pass. Its result is alignment. On a semi-dry surface it should be carried out faster. It not only smoothes the surface, but also displaces moisture from the inside, which promotes rapid drying.
2. The second is smooth grout. All irregularities and defects are smoothed out. The surface is made smooth and durable.

In both the first and second stages, make it a rule to use the device only for its intended purpose. Read the instructions and specifications carefully. This especially applies to the selection and installation of grinding parts, as well as when working on an inclined surface. If the angle of inclination is unacceptable, it is better to use another machine that goes well on an incline. If the unit is moving in a narrow place, do not stand in its path, but choose a level place for parking. Do not forget about timely maintenance of the gasoline engine - change the oil and filters.

For safety:

1. Always carefully inspect the unit, replace damaged and worn parts in a timely manner;
2. Use protective elements: headphones, glasses, respirator. If you neglect them, then this is a direct path to diseases of the respiratory tract, hearing and vision;
3. For long-term work, choose high-quality equipment that does not vibrate much. Vibration diseases of the hands and joints are a reality, not a myth;
4. Remember how to turn off or lock the sander in an emergency;
5. All rotating components, in addition to being sharp and dangerous, also become very hot, so stay away from them during operation and immediately after turning off.

Compliance with personal safety, instructions and proper care of the trowel is a guarantee of its long and effective operation.

Price

Different models differ in technical characteristics, of which important indicators are engine power, disk diameter, and performance. It is these indicators that influence the price of a helicopter trowel. The cost of single-rotor devices varies from 60,000 to 170,000 rubles, double-rotor devices - from 270,000 rubles to 1,600,000 rubles. After completing construction work, do not forget to clean up. An industrial vacuum cleaner will help with this.

Having looked at the information about the model called “Helicopter”, we can say with confidence that the quality of the instrument is at the highest level. If we compare it with foreign analogues, the trowel is a leader in many respects.

Processing area

Small areas (up to 500 square meters) can be easily and simply sanded using electrical equipment. Based on the design, you need to choose a single-rotor machine. These are devices that have one propeller (blade blade) installed. They are lightweight and safe to use. The blades are always covered by a protective frame.

Large surfaces require a powerful and fast machine. Reviews online indicate that such complex tasks require gasoline units. In addition to the gasoline engine, it is worth choosing a more complex design - a two-rotor one. This is a large grinding equipment that has 2 propellers with a protective frame. When rotating, the trajectories of both rotors intersect, which gives better alignment of the screed. In one pass, such a machine covers 2 square meters of area. It is clear that its operating speed is much higher than that of a single-rotor. Often such equipment is equipped with a seat with a joystick control. In general, complete comfort: high speed and convenient control.