Power Trowels

A concrete power trowel is a machine with rotating blades that finishes and smooths a fresh slab while it is setting. The turning rotor presses on the cement paste, closes the pores and gives the surface a smooth, hard and abrasion-resistant finish. The blades usually run at around 60–150 rpm, and a single machine finishes several hundred square metres in the time that hand-floating with a trowel would take a full working day.

A petrol power trowel with a Honda GX or Briggs & Stratton engine delivers the highest power and full autonomy, which is why it works on large sites and industrial floors. An electric power trowel supplied from a 230 or 400 V mains runs quietly and fume-free, but its range is limited by the cable — it suits interiors and garages. A battery power trowel produces no exhaust and needs no cable, so it works in enclosed rooms, while its run time is limited by battery capacity.

Floating starts once the concrete reaches the right hardness — usually 2–6 hours after pouring, depending on temperature and humidity. A simple test is the boot imprint: when the operator leaves a mark about 3–5 mm deep, you can drive the machine on with a float pan, and after further hardening switch to blades. On hot days the window shortens to as little as 1–2 hours, which is why a large slab is finished in stages.

For a garage, a patio and a smaller home floor a single-rotor walk-behind power trowel with a disc of about 60 cm is enough, for example the Barikell 6-60 with a Honda GX 160 engine or the electric Beton Trowel BT 60 E. A 60 cm machine is light and agile and works well along walls. For areas of several hundred square metres it is worth considering a larger disc of about 90 cm, such as the Barikell 4-90, and in interiors without ventilation an electric or battery drive.

A single-rotor power trowel (walk-behind) has one rotor, and the operator walks behind the machine holding the handle — it handles areas from a few dozen up to several hundred square metres and copes well at the edges. A twin-rotor power trowel (ride-on) has two discs and an operator seat, and its output reaches several thousand square metres per day. Single-rotor machines such as the Barikell 4-90 are chosen for small and medium floors, and ride-on machines such as the Barikell MK8-120 HCS for halls and warehouses.

The disc diameter is matched to the size of the floor and access to the edges. A disc of about 60 cm is light and agile — it works in garages, on small floors and along walls and corners. A disc of about 90 cm is the universal choice for medium and large areas. A disc of about 120 cm is found on twin-rotor ride-on machines and handles halls and floors measured in thousands of square metres.

The price of a power trowel depends on the drive and the size of the machine: light single-rotor electric models with a 60 cm disc are the cheapest, while ride-on twin-rotor industrial machines with discs up to 120 cm cost many times more. Renting can pay off for a one-off pour of a single floor, but for companies and concreting crews that finish floors regularly, a purchase pays for itself after just a few jobs of several hundred m². There is no daily rental rate, and a professional Enar, Beton Trowel or Barikell machine lasts for years.

For work in enclosed rooms, basements and buildings without ventilation, the best option is a battery power trowel, which produces no exhaust and needs no cable. Battery models from Conmec Europe and Beton Trowel run on interchangeable batteries, which lets you work several hours without a break — once one is flat you simply swap in another. An alternative is a 230/400 V electric power trowel where mains power is available; a petrol drive is not used indoors because of carbon monoxide.

Engine power is matched to the disc diameter and the scale of the work. Single-rotor 60 cm machines use smaller units such as the Honda GX 160, which give enough torque for garages and smaller floors. A 90 cm disc needs a stronger engine, like the Honda GX 270 in the Barikell 4-90, to keep the blade speed up under greater resistance. Ride-on twin-rotor trowels for halls are driven by large engines, such as the 35 HP Briggs & Stratton in the Barikell MK8-120 HCS. An underpowered engine loses revs under load and leaves an uneven finish.

Power trowels use two basic types of fitting: a float pan (disc) for the initial levelling of a fresh slab, and blades for the actual floating and polishing. Blades come in a universal (combination) version and a finishing version, and they are matched to the machine diameter — 60, 90 or 120 cm — and to the model. Blades, pans, guard rings and drive belts are consumables replaced as they wear; compatible fittings for Enar, Beton Trowel and Barikell machines are in power trowel accessories.