Waxing Basics for Artificial Snow

With the so-far dry winter skiing season in the Midwest, many skiers are taking advantage of several local alpine areas that are open to Nordic skiers. While this is a boon for on-snow time, it can make for a frustrating waxing experience. In order to understand how to wax for artificial snow, it helps to have a basic understanding of how it is made.

Snow guns come in a variety of types, but they all make snow in basically the same way. A pipe supplies a large amount of water to the gun, where the water is broken up into very fine droplets through a nozzle or fan. These droplets are then distributed into the air where they freeze into a bead or pellet as they descend. All of this makes for snow with a fairly high moisture content that resembles a transformed natural snow crystal. Combine this with manipulation by a grooming device, and you immediately get snow that is wetter and effectively older than its age would indicate. Keep in mind that alpine areas groom on a daily basis whereas most local Nordic areas groom on something more like a weekly basis. Before artificial snow is groomed, the bead-like shape of the crystals and high moisture content cause some of the beads to freeze together while other particles float in this aggregate. These factors combine to make a very "sticky," hence, slow skiing surface.

By comparison, natural snow falls from the sky as a crystal, with numerous sharp points and edges. As this snow is groomed and skied upon, the points break off and melt down, transforming the crystals into something resembling a pellet or bead - the same thing that comes out of a snow gun.

Glide Waxing

The base structure one uses for artificial snow is not any different than that used for natural snow of the same temperature. However, because of the additional moisture in artificial snow, a slightly warmer grind can be advantageous at warmer temperatures. The choice of wax itself is fairly straightforward; one should choose the wax based on the snow temperature. The point to keep in mind here is that artificial snow is more abrasive than natural snow, but also wetter. The choice, then, is twofold: does one go with a colder wax for the added durability (remember that colder glide waxes such as Swix CH4 are harder and stand up to abrasion better than warmer waxes such as Swix CH8), or does one go with a more conventional choice because of the additional moisture (warmer waxes such as CH8 repel water better than colder waxes such as CH4). The best decision would be based on testing. There are several products, though, that help deal with this additional moisture, namely fluorinated waxes and Swix HFBD -- a new product developed for the 2002 Winter Olympics in Salt Lake City, where competition was held on primarily man-made snow. Obviously in a training situation one doesn't need to use fluoros or HFBD, but in a race, the additional dirt repellency and durability offered by the fluoros and the HFBD are advantageous.

Kick Waxing

Kick waxing is reasonably straightforward on artificial snow. The key word is klister. Since man-made snow is, by nature, frozen by a mechanism similar to natural snow that has melted and re-frozen, it is inherently transformed and klister is a must. As is the case with glide wax, the abrasiveness of artificial snow can wreak havoc with kick wax. The easy way around this is a layer of klister binder, Swix KR 20 Base Klister (green) ironed into the base and cooled, with the klister of the day applied on top. As a final touch, the conditions in man-made snow often dictate covering the klister with a hard wax; this helps repel any dirt and loose beads of ice that might be in the tracks. Because of the snow's high moisture content and manipulation by grooming equipment, the covering layer of hard wax may need to be warmer than that predicted by the snow temperature.

Of course, the simplest way around waxing trouble is waxless skis. They won't provide fool-proof kick, but given how variable the snow conditions can be around the trail (some areas glazed, others soft and wet, etc), waxless skis can provide a good compromise.

One other point to remember is that artificial snow, like natural snow, can become transformed by the local weather. In other words, if the relative humidity is low and there is, say, a wind from the north, artificial snow will dry out a bit just like natural snow, although it won't dry out as much as natural snow would. In this case, one would choose waxes geared towards drier conditions. Likewise, if natural snow is falling on top of the artificial snow, one's wax choices would trend back towards natural snow a bit more. For example, one might be able to go to hard wax rather than klister.

Finally, because artificial snow is mechanically manipulated so much, it can get very dirty. As a result, one should be conscientious about cleaning one's skis and re-waxing soon after skiing on artificial snow in order to keep the bases in good shape and to prevent oxidation. Waxes penetrate better, perform better, and are retained better in clean bases. Hot scraping two or three times with Swix CH10 is time better spent than simply brushing out the old wax and applying several new layers of wax.

About the authors: Corey Coogan and Bohdan Stepchuk live in Hudson, Wisconsin, and ski for Alpina Racing. Corey is training full-time and coaches cross country running and Nordic skiing. She is a top regional skier, placing 3rd in the Minnesota Finlandia and 16th at the Birkie. Bohdan works as an engineer and trains in whatever other time he can find. He is a consistent top-25 finisher in the Noquemanon Ski Marathon.