In the “old” days tuning used to mean sharpening and waxing and base repair if needed. Today, with shape skis, tuning means all that plus edge beveling, edge polishing and base structuring.

Edge Beveling
To look at a ski edge one might assume the edge is square. Actually that’s not the case. Most skis have bottom, or base, edges that have been beveled from 1/2º to 1º. And side edges that have been beveled from 1º to 2º. This leaves an acute angle to the edge that makes the ski forgiving as it enters the turn, and helps it hold well on hard snow or ice. For extreme conditions (racing) base edge bevels might be from 0º to 1/2º and side edges might 3º or more. This makes the ski more demanding to ski on but the super acute angle helps the ski hold on even the iciest slopes.

Two years ago, we did a two-part study on ski tuning. Our goal was to learn both the degree to which ski manufacturers followed their own tuning recommendations on new skis and secondly, to what extent a performance skier could feel the difference between the various base and side edge bevels the manufacturers recommended.

The first part of the test involved using a Laser angle finder to test the edge angles of new skis. We wanted to find out if the side and base edge angles that came on new skies matched the recommendations that the manufacturers publish. What we learned is that new ski angles are nowhere close to what is recommended.

When we measured the base edge angles we found huge differences from the manufacturers recommendations. We found huge differences in edge angles between one ski and its mate, between the angles on one side of the ski compared to the other side. There was even a difference between the front half and the back half of the same edge!

As we investigated this further we learned that while manufacturers all recommend base and side edge angles, none of them are implying that their skis have these angles when they are new. Quite the opposite, most manufacturers recommend that their skis be tuned to the correct edge angles before they are skied on.

The second part of our test was to actually ski on different edge angles to see if we could feel how the ski changed when different base and side edge angles were ground into the ski.

We started with two identical racing skis mounted with two identical bindings. For our first test we varied just the base edge. We tuned ski A to 1º base edge and 2º side edge. The ski B was 1/2º base and 2º side. We could clearly feel how much quicker ski B was to start the turn and how much less angulation it took to hold. We also learned that a 1º base edge angle was more forgiving for less aggressive skiers.

For the second part of the test we tuned the base edges of both skis at 1/2º. Ski A had a 2º side edge angle and ski B was tuned with a 3º side edge. In free skiing we found that it was difficult to feel much difference between the two side edges. However, when you really laid the ski over and ripped (like running gates in a slalom course) the 3º side edge held much better. We find that most recreational skiers prefer a 2º side edge, racers a 3º. An exception to this would be young, lower level junior racers. 3º side edges are demanding to ski on. They are unforgiving in that they won’t slide or skid which can be harmful to the knee. Many coaches recommend that younger skiers use a 2º side edge.

Waxing
When a ski glides across the snow, friction melts the top layer of snow and creates a thin film of water. The shiny tracks your skis make in the snow is this frozen layer of water. If you looked at the base of your ski under a high power magnifying glass it would look porous like the surface of a sponge. When the ski glides on the layer of water there’s a suction created between the layer of water and the pours on the bottom of the ski. This slows the ski and makes the ski difficult to turn.

When the ski is waxed, hot wax is melted into the ski almost like water will fill up the pours of a sponge. When a waxed ski glides across the layer of water, friction draws out minute particles of wax which break the suction between the ski and the water layer. This helps the ski to glide and turn much easier.

Now for the bad news, for the average skier, a downhill ski should be waxed about every 16 miles, which is about every other day on the snow. Waxing is definitely something that the average skier can do themselves. There are also simple wipe-on waxes that are work pretty well. Most recreational skiers should probably be waxing their equipment a whole lot more often than they do.