I bought a device just for that procedure from Tognar.com
It works great and wasn't expensive. The trick with doing it freehand is making sure you can produce a 90 deg edge. It can be done, however it's worth getting it right.
It can be frustrating getting the right tools you need for tuning skis. This past summer I designed and produced my own edge beveler because nobody really makes one that de-burrs, relieves the side wall and files the edge (in one tool). Ski tuning should be fun, but sometimes you have to color outside the lines to get what you want.
Check out Tognar though, I get most of my tuning supplies from them. They're fast and reliable.
<FONT COLOR="#800080" SIZE="1">[ February 01, 2002 07:45 AM: Message edited 1 time, by Rock'n Doc ]</font>