The main reason for grooming is to make the snow consistant and safe to ski, jump and board on. For competitions there are special requirements and details that demand extra knowledge and skills.

The general snow preparation is done with the same basic machines for all the snow disciplines. The 200 – 500 horsepower grooming machines are from 2.5 – 7 meters (8 – 22 feet) wide. Good driving routines are important since every hour in a machine is expensive (labour, fuel, fluids, parts, maintenance, etc). The basic grooming is, in normal conditions, done by using mainly the front blade and the tiller.

Front: The front blade is controlled by a hydraulic system. It is used to push snow around, clear out bumps and dumps, create even downhills and courses such that the surface is re-established after heavy use or snowfall (or established initially after snowmaking) 

Tiller (rear): The tiller is the most important piece of equipment for grooming, and will create a more consistant and compact surface by altering the distribution and size of the snow crystals. Speed, down pressure, angle and direction of the tiller (forwards, backwards) are adjusted according to the nature of the snow at the moment of grooming. 

For ski jumps and alpine hills, it is also often necessarry to use a winch

The winch is used when moving snow or grooming on steep hills where it is required, for safety, to anchor the machine’s winch cable to a winch anchor point at the top of the hill. When grooming using the winch-cat it is important to drive very slow such that the snow becomes as compact as possible. 

The fuel/diesel cost for a grooming machine is between 10 – 25 liters per hour, depending on the size of the machine. As in other industries, electric models as well as models fueled with hydrogen (See “News” section) are also now available.

Currently, fully electric model large grooming machines can operate for 2.5 – 3 hours (both Pistenbully and Prinoth). The Finish model EV snowmobile in the photo has a 9.5 kwH capacity and can drive 40 km before needing recharge.

The special and detailed grooming requirements for each of the snow disciplines are covered in the chapters below. Some of the disciplines require special attachments (see photos below of front mounted snow blower and snow bucket, and rear mounted track setter).

Snow density

The density of the snow varies a great deal between cold new snow and old compressed snow. Cold, dry new snow (powder snow) may have a density as low as 100 kg/m³, while snow that has partially melted, frozed again and been compressed can have a density of 500 – 550 kg/m³. Grooming machines will (usually) increase the density, and provide better ski conditions. For optimal competition conditions in Cross-Country, Biathlon and Ski Jumping, the density should be around 450 kg/m³, for snowboard ca. 530-550 kg/m³ and for alpine ca. 530 – 620 kg/m³ (depending on the competition event). When both recreational and competitive alpine skiers share the same course, the density should be reduced a bit.

Newly groomed snow on this combined recreational- and training course has a density of ca. 350 kg/m³ (less than a competition course)