Fluoros stick to fluoros much better than they stick to hydrocarbon waxes. If the pores in your bases are filled with hydrocarbon wax, your race waxes lose durability. Filling those pores with an HF wax gives a strong base of fluoros for your race wax.
The more information you know about your skis, the better you can use them to your advantage on the race course. The turn radius minimum printed on the ski is just that—a minimum. The actual turning radius of the ski may be greater, giving some skis a straighter line than others. In addition, some skis will shift slightly in the mold, giving one edge a shorter turn radius than the other. We measure sidecut as part of an Olympian prep.
Molybdenum, or moly for short, is a friction reducing additive that makes wax black. It has been found to work well in the dry friction created by very cold conditions (sharp snow crystals), in wet conditions, and in dirty snow (repels contaminants), so it has been mixed with Swix HF waxes to create Swix HFBW (black wolf) waxes, which are now used in almost every race situation instead of the regular HF waxes. You can also buy bars of straight moly, which is low fluoro. Our World Champion prep includes a moly thermobag treatment.
Base bevel, the angle of the metal edge that is flush with the base, is the single most important aspect in ski tuning because it controls the reactivity of the ski and it is really easy to get it wrong. Very slight tolerances translate into large differences in performance on firm snow. A difference in .5 degree at the base bevel can translate into a difference of an inch or two moving up your leg from your knee to your hip. In other words, you would have to roll your knee 1 inch further before the base edges into the snow.
As a tech for the U.S. Ski Team, it was my job to find those fractions for my athlete. Our tests showed that one of the most effective ways to create a faster ski is to modify the base bevel. We tested three identical models of skis prepared with the same grind. The only variable was the base bevel. We tested the skis on a run that had a steep, a medium and a flat pitch. The results showed that the .5-degree was the fastest on the steep pitch, the .75-degree was the fastest on the medium pitch and the 1-degree performed the best on the flats. The .5-degree base bevel is the most reactive, so on steep pitches, this ski comes around much faster. The higher angle of the 1degree bevel allowed that ski to perform the best on the flats because it draws out and lengthens turns by smoothly rolling into them without the abrupt edging characteristics of a less beveled ski. As you might expect, the ski with the .75-degree bevel performed the best on the medium grade slope. It is neither too reactive nor too slow to react–perfect for a medium pitch. You can see that it is important to choose the base bevel according to the terrain you may encounter on a regular basis and your abilities as a skier. For example, if you often ski steep pitches and you are looking to improve your time on the steeps, you may want to try decreasing the base bevel on your skis.
Stonegrinding is the process of flattening and or truing the base material of a ski flat in relation to its base edges. A truly flat ski is evenly flat from one base edge to the other. This is accomplished by running the base material of the ski over a ceramic composite stone within a stone grinding machine. A series of different patterns are used to flatten and smooth the base material until the base is even and flat.
Once the skis are flattened, then a specific base grind pattern is selected for racing. The base pattern controls the movement of water under the skis. Different patterns are selected for discipline, snow type, snow temp, and humidity. See the most common Edgewise alpine or Nordic grinds.
Though many new skis come to the consumer with a nice looking finish grind on the base, the preparation is the result of mass production and lacks the attention to detail needed to make each individual ski perform at its best. Just as cars off of an assembly line are fine tuned at the dealership before they are put on the road, skis should get individual attention from a ski technician before they hit the slopes.
Take a look at your new skis. One of the first things you will notice is the base grind, or structure. Most of the time this structure is a type of cross pattern with scallops that help move water under the ski. Even if this grind looks incredible, it will not ski to its potential if the ski hasn’t been properly tuned.
It is nearly impossible to detect how much base bevel a ski has without the use of a true-bar because the angles are measured in fractions of degrees. These small tolerances can, and do, make a big difference in how a ski performs. Base bevel is the heart and soul of ski performance, and is one of the most overlooked aspects of ski preparation. Even the most incredible grind is useless if the skis have too much base bevel. New skis should be flattened on a stonegrinder before they have the proper base bevel set. Then an appropriate grind can be applied.
Today’s skis are under much more stress than they were just a few years ago. New side-cuts, plates, and lifters produce great forces that push and pull on the core material that makes up the ski. These forces act slowly, and as they develop over time, you may not notice that there is a problem with the performance of your skis. A pair of skis will rarely make it through a whole season without developing some curvature of the base, which in turn, causes change in base bevel angles. As mentioned before, without a true-bar, the angles can’t be detected, so take old skis to a reputable shop at the beginning of the season to have them looked at. If your skis are concave or convex (most problems are usually under foot) it will be necessary to get the base of the skis flattened and ground on a stonegrinder. Have them rechecked mid-season, or at any point that you feel performance has deteriorated. (This is also a great excuse for bad days on the hill.)
The pit-crews in Formula One racing will select different tires for the different events and different types of tracks that they encounter throughout the year because each type of tire performs best in particular conditions. The same idea holds true for base materials and structures in ski racing. Where you ski, and the events in which you ski, both play a big part in the type of grind that will be fast for you.
Wetter conditions will require deeper scallops (more water) whereas dryer conditions will require a smoother interface (less water) between the snow and the base material. So, a heavy crosscut structure may work well in a warm, wet climate like California, but be the worst selection for the colder conditions of New England.
In technical events (GS and SL) it is important to have a grind that is not too aggressive because of the great amount of lateral movement in these events. A smoother, less aggressive interface between the base material and the snow will make a ski faster. A good rule of thumb for a slalom or GS grind is that you should be able to see the structure but not feel it.
Grind selection for speed events is more complex. Various combinations of construction (flex), base material, and side cut are better suited to certain conditions. Those conditions then determine which grind will be the fastest. A new, computer-controlled stone grinder, programmed with the results of extensive testing with OSV (Austrian National Ski Team), has the ability to generate an infinite number of grinds to meet specific temperature and condition requirements. This information, in the hands of an experienced technician, is invaluable in determining a fast grind.
If you have access to a technician with one of the new grinders, there are really two ways to go about getting the most out of your skis. If you have one or two pairs of skis, the best plan is to go on line to a weather website like www.accuweather.com. Use your racing schedule to figure average temperature, humidity and snow type for the races that are most important to you, or decide based on the conditions you will be encountering most often. Bring your data to your ski service provider. Those who have the luxury of owning a quiver of skis you can choose from a variety of grinds to cover all of the conditions that you may encounter throughout the year. Again, collect temperature, humidity and snow type data for each set up and have your technician choose the right ski for each grind. See the most common Edgewise alpine or Nordic grinds.
Side edge bevel is the angle of the vertical side of the metal edge and controls how powerful the ski feels on edge. Remember that while side edge and base edge are independent aspects of the skis performance, without proper base bevel, nothing else will work right. The side edge bevel for most racers is set at 3 degrees.
The sharper the side edge bevel, the more edge hold you will have. On the other hand, the sharper the side edge angle, the less durable the edge will be. A 2 degree bevel will not hold as well as a 3 degree bevel but it will stay sharper longer and if you hit a rock the damage will be less. A 2 degree bevel is ideal for freeskiing, especially off piste, due to its durability. The edge hold of a 3 degree is perfect for ski racing on hard icy slopes.
So which side edge bevel do you need? Generally speaking, if you are a recreational skier you should be using a 2 degree bevel, with exceptions for powder, when a 1 degree is probably fine. If you are a particularly strong recreational skier you might enjoy the power of a 3 degree bevel. As a general rule, U8s and U10s would be skiing with a 2 degree bevel, more aggressive U10s and U12-U18s on a 3 degree. A few elite racers use a 4 degree. Your ski technician or coach can help you decide on appropriate angles if you are unsure.
When you go into a store to purchase a pair of skis, the last thing on your mind is how the sidewall of the ski is going to affect your performance. You may not have known that it could even affect your performance. In fact, you may not even know what a sidewall is. You should. Understanding the effect that sidewall design has on your skiing will help you get the most power and performance from your skis. The sidewalls are the material above the side edge and below the topsheet of a ski. When a ski is on edge, the sidewall is in the snow. Just as a boot at aggressive angles can hit the snow and inhibit edgehold, (known as booting out), the sidewall, if angled improperly, can create the same phenomenon. Sidewall material must be removed from the ski so the metal edges can dig deep into the snow without interference.
The other challenge presented by excess sidewall material is the difficulty in achieving precise side edge bevels. Before you can accurately pull a file on a side edge, sidewall material has to be removed. Otherwise, your file will be resting on sidewall material instead of directly on the metal edge. As a result, you will pull negative angles instead of the angles you want.
Shaping sidewalls is a very difficult task. If you have no experience at this process, I strongly recommend that you have your ski technician set up the sidewalls for you. A file will not cut the fiberglass that is used in the construction of the sidewall, so there are specific tools that have been developed to cut the material and pull it away from the metal edge. Note that shaping sidewalls is much more involved than just removing the sidewall bumper with a sidewall planer.
After the sidewall material is removed, the side edge can easily be pulled with a file and file guide. Side edge bevel controls how powerful a ski feels in the turn, as opposed to base edge bevel, which controls how reactive a ski is at the beginning of the turn. As bevel degrees increase in number, the angle created becomes more acute and therefore, more aggressive. An aggressive angle provides more power and edge hold throughout the turn. The trade-off is in durability. A 3-degree side edge bevel is fragile and will dull faster than a 1-degree bevel. It will also sustain more damage from hitting rocks.
First, brush the base out with a copper brush. Then drip on a generous amount a mid-temp range Low fluoro wax or a hydrocarbon. Iron it in making sure that there is enough wax to provide a thick layer on the base and that the iron is hot enough to ensure a good bond between the wax and the base. This ironing procedure is normal, but sometimes a person rushes through storage waxing and the wax is not really heated outside of that it becomes liquid. The ski bases often times don’t even become warm. This will result in air between the base and the ski and less protection.
If waxing skis or a board with metal edges, slop the wax over the edges and cover them, too.