Scenario: You tuned your skis meticulously the night before……
You picked up your skis from the local ski tune shop earlier that morning…..
First run, first gate…. you crank it over hard to engage your fresh edges in hard pack snow / ice….and wam-o- you slide out taking a gate with you down the face of the mountain – total shock and awe – as you wonder what happened during your cold journey to the bottom of the course.
The classic: sidewall was not planned / pulled back enough to expose enough new steel when sharpening the side edge. OR, the file is skipping on a case hardened side edge OR, the file is placed in the guide at the wrong orientation. [Files have an arrow to indicate direction of cutting, and need to be held at ~45 deg. to the edge for maximum effectiveness]
How does this happen?
The shop [or you] are in a hurry, or, may not be paying attention, or may not know any better….
How is this prevented?
Always, always, always start with a diamond [moonflex, DMT, etc] as a first pass on the side edge. This does two things. One, the diamond will remove the case-hardened [shine] of the outer side edge. If a file is needed to sharpen the edge, it will not “skip” down the edge and fail to remove material. Thus, the edge will not be sharpened….. Two, as the diamond is pulled down the edge you make sure it has consistent and constant engagement with the mental….. a certain friction is felt that is even….
if not, its the sidewall that is preventing the file from engaging the metal edge….. the sidewall must be removed [planned back] to expose enough steel edge.
A side edge planer by Swix.
A quick check:
Take a felt black marker and make some lines or dashes down the metal side edge you are about to file/ sharpen. If the black marks are not removed from the edge when sharpening, material / metal is not being removed; check the sidewall!!!!
Note: In general, it is important to always be aware of the subtle changes in friction / feeling that a tool makes when dragged over the edge of a ski. Practice will make perfect.
Final Thought: Have a fancy new electric edger and think none of this applies to you….. think again….and then check your sidewall and use a black marker on the steel edge to check!