Tuning with Willi Wiltz

Posted by Scott Churchill on 30th Nov 2018

Earlier this week I braved a stormy five-hour trip north to Gresham, Oregon (just east of Portland proper) to attend a tuning clinic with master tuner Willi Wiltz, it was worth every mile.

Wiltz has been making skis scary fast for 3-decades, he has tuned for Tommy Moe, Daron Rahlves, and Bode Miller and snowboarders Nate Holland and Shaun Palmer, to name a few. Now off the World Cup circuit his knowledge and skill have found new venues; at his tuning and repair shop, Finish Line, located at the base of Sugar Bowl in Tahoe and at Toko sponsored tuning clinics dotted across the United States.

At first meeting you get the impression he is genuinely glad you showed up, quick to laugh he shakes hands with the solid grip of a craftsman. When he is in his element, file in hand, there is an economy of motion, fluidity refined through years of repetition.

Thirty-odd-years of knowledge is a lot of territory to cover in a two-hour clinic, but Wiltz refined it well and delivered key points regarding base structuring, edge prep and waxing, some of which are listed below.

  • A ski base gets increasingly fast after it is structured, to a point, then it will start to slow, use a steel brush to revive the structure and open the base, this will bring back the speed.
  • “Bevel consistency is everything,” -Bevel from the very tip of the ski to the end of the tail. Beginning and ending the bevel at the contact points (where the ski touches the snow) creates an abrupt change, it is better to create a uninterrupted angle along the length of the ski.
  • “Base bevel only increases, it never decreases,” -The abrasiveness of snow, especially hard snow, will increase base edge angle over time. Edge material wears away more quickly than the base.
  • Dull files can increase the base bevel -A dull file requires more pressure to cut, that pressure can create too much base bevel. Wiltz recommends 16 or 20 tooth/cm files for base beveling (the more teeth/cm on a file, the finer the cut).
  • After you have cut a side or base bevel wrap 320grit aluminum oxide or silicone carbide sandpaper around a file and lightly sand the edges with long strokes (be sure to use a bevel tool), this technique prepares the metal to better accept diamond or aluminum oxide stones.
  • A side bevel guide in conjunction with a true bar is a easy and accurate way to check side bevel angles. (photo to follow soon).
  • De-tune edges using a gummi stone only! This allows the edge to be brought back to sharp if needed.
  • “What matters is the final product, not the tool.”
  • Hot scrape skis to clean them instead of using a chemical base cleaner. -Soft hydrocarbon waxes like Swix CH10 or Toko S3 Yellow penetrate deeply into the base, scraped while hot the wax pulls out old wax and impurities and at the same time moisturizes the base. Repeat until wax shavings appear clean. Finish with a brass or copper brush.
  • Use snow-forecast.com for up to date info on major areas. This is a major help with wax selection if you aren’t on the hill!
  • If unsure which wax to use always err on the cold side.
  • Be wary of “over juicing” junior skis, developing muscles may not be able to hold on, too fast a wax job may actually cause them to blow the course.

Of course there was much more information than this, and Wiltz tuned as he talked so it was possible to see the techniques first hand. Luckily there are a few more stops on his tour, if he is coming through your neck of the woods make the effort to see him, your skis will thank you.