Petrol Power Cutters: Concrete and Stone Cut-Off Saws

A handheld power cutter suits short cuts in walls, pipes and awkward places, while a wheeled floor or road saw is for long, straight and deep joints in concrete floors and asphalt. Some handheld models can be mounted on a cart for straight cuts.

Handheld power cutters usually have 60–80 cm³ two-stroke engines rated at 3–5 kW, while floor saws use 196–390 cm³ four-stroke engines (6.5–13 hp). A two-stroke engine is light and revs up quickly; a four-stroke is more economical and quieter. See differences between two-stroke, four-stroke and diesel engines and engine displacement, power, torque and RPM: how to compare engine-powered equipment.

Handheld power cutters take 300–350 mm (sometimes 400 mm) blades and cut 100–125 mm deep, while floor saws use 350–500 mm blades for depths up to 150–180 mm. Choose the diamond blade for the material — concrete, asphalt or stone — and check the arbor size. Read how to choose a diamond disc and how to choose the correct disc diameter.

Wet cutting from a water connection or tank reduces hazardous silica dust, cools the blade and extends its life. Check for a water connector, valve and convenient supply system, and use respiratory protection when cutting dry.

A decompression valve and easy-start system make starting a large engine much easier. Two-stroke models run on a petrol and oil mix, and a multi-stage air filter protects the engine from concrete dust. Read fuel, engine oil and two-stroke mix: how to choose and use them correctly.

Handheld power cutters usually weigh 9–13 kg, so an anti-vibration system, comfortable handles and good balance matter. Noise reaches 100–110 dB, so safety glasses and hearing protection are essential. See how to choose safety glasses and how to choose hearing protection.

Work only with the guard fitted, hold the tool with both hands and avoid cutting with the upper quarter of the blade, which causes kickback. If the blade pinches in the cut, stop the engine immediately. See how to safely use internal-combustion-engine tools and equipment and what to do if a disc or drill bit jams.

Concrete dust clogs the air filter quickly, so it must be cleaned or replaced often, and belt tension and the spark plug checked regularly. Choose a model whose filters, belts and starter parts are easy to find. Read how to maintain and store motor tools and engine-powered equipment and how to choose spare parts for gasoline and diesel engines.