Helpful Tips On Definitive Fin Measuring

One of the things I wrote about in last issue’s article was the importance of keeping a ski journal for your upcoming season. One key item that is kept in your ski journal is your fin settings. Whether you are a fin moving fanatic or not, it is very important that you have your settings written down. Your ski takes abuse each and every day, so there is a high probability that your fin settings will change over the course of a season. Many slumps have been caused by unintentional fin changes. Don’t let this happen to you. Know how to measure your fin and be sure to log it in your journal. If a local “fin doctor” messes with your fin, log it. If you go to ski school and your coach changes your settings, log it.

It is time for the precedent to be set with regard to measuring fins. In the following captions you will learn proper techniques and gain helpful tips to make your experience easier and more productive.

Fin Depth (A) is the point on the fin that is furthest away from the bottom of the ski. Since this is the easiest, most repeatable measurement you can take, I recommend it be your first.

Place your ski on its side with the tip to your left. Lay the bottom side of the shaft on the fin so that the nose touches the bottom of the ski and the dial extends out past the deepest part of the fin. Hold the nose of the caliper perpendicular to the bottom of the ski with your left thumb and then slide the caliper in with your right hand until it touches the fin. Take a few measurements in slightly different locations. The location that gives you the largest number is your Fin Depth.

Fin Length (B) is the distance from the leading edge of the fin to the trailing edge of fin, as measured from the bottom of the ski. Basically, it is the point from which the fin sticks out of the ski in the front to the point at which the fin goes back into the ski at the rear. To accurately measure Fin Length, place your ski on its side with the tip to your left. Hold the caliper so that the bottom side of the shaft is flush to the base of the ski and measure with the tips of the calipers. It is a good idea to use the center of both tips for your measuring point. Open up the caliper and use your left thumb to hold the tip of the caliper against the front edge of the fin and flush to the base of the ski. Then slide the caliper closed until the center of the other tip hits the back edge of the fin, flush to the base of the ski. This measurement is not as easy to take as the “jaws” length measurement that many skiers use. The advantage with the “tips technique” is that it is accurate from one caliper to another, thus making it the only way for you and other skiers to compare settings.

Fin Distance From Tail Measurement (C and D) is by far the hardest fin measurement to accurately reproduce. By definition, it is the distance from where the back of the fin retreats into the ski to the back edge of the ski.

Stand your ski on its tip so that the bottom of the ski is facing you. Use your left thumb to hold the nose of the caliper against the base of the ski and the back edge of the fin. By standing your ski on its tip, you can use gravity to hold the caliper flush and vertical, which will help to add accuracy to this measurement. Focus on using your left thumb to hold the nose of the caliper flush to the base of the ski. Close the caliper until you hit the back edge of the ski. There is no set point on where the caliper should hit the back of the ski, so wherever it first touches is your spot. It is nearly impossible to duplicate this measurement, so take a few measurements and average them out.

Fin Leading Edge (E) to Tail of Ski Measurement is the distance from the leading edge of the fin to the tail of the ski. This is probably a new measurement for the majority of readers. The purpose of this measurement is to help keep our fin movements as accurate as possible. Basically, this measurement helps to nullify the inaccuracies in the Fin Distance From Tail Measurement.

Lay your ski the same way you would to measure the Fin Length or Fin Depth. Open the caliper all the way and set it on the fin, flush to the bottom of ski. Place your left thumb on the nose of the caliper and slide it until it touches the front of the fin. Use your right hand to slide the caliper in until you touch the back edge of the ski.

For those of you that used to use the “jaws” technique for measuring the Fin Length, this is basically the same except that you are measuring to the back edge of the ski. This measurement will not be accurate caliper to caliper, but will help you when it comes time to make a fin change. Most of us use 8-inch calipers for fin measurements. The Fin Leading Edge to Tail of Ski Measurement is usually just larger than 8 inches. For users of dial calipers, I recommend that you open your caliper to its 8-inch mark. Then open the caliper to 8.100 and scribe a pencil mark on the caliper. Do this for 8.200 and so on to make taking the Fin Leading Edge to Tail of Ski faster and much less confusing. Users of digital calipers don’t need to concern themselves with this.