Gear West Signature Flex Tester

Audrey Mangan · January 9, 2012

Flex2 gear west — Gear West Signature Flex Tester

Over the past year Gear West has been designing and building the world’s foremost Nordic ski flex tester, and we are pleased to announce that it is now up-and-running! In order to create the Gear West Flex Tester, over $20k in hardware and lots of man-hours have been directed to the project and our final software solution. The technical team includes Gear West employees and former engineers, Matt Liebsch and Geroge Mehr, our friends at Segla LLC, George Stickler and Jim Johnson as well as Software Developer, Jim Walters. Our goal in creating this machine was to unlock the “black box” mystery of cross country ski flex analysis.

Other flex testers on the market use displacement, springs, force sensing resistors or camber length measurements to obtain an approximation of flex. Gear West is using the most accurate resource available… load cells. We are not approximating flex based on secondary parameters or using inaccurate FSRs (force sensing resistors) prone to saturation pressure. Our load cells are accurate within 4 hundredths of a kilogram. This allows our flex tester to discern the slightest variations in flex.

While we have perfected the use of our hands, eyes, traditional flex bench, and single point closure methods for testing skis, our newest tool brings these together in a novel and highly controlled method for analyzing ski flex.

With the Gear West Flex Tester, we can determine the following:

The ideal weight range for a ski
The absolute quality of flex
The characteristics of a given ski, or what conditions in which it will perform best – snow type, track firmness, stability
How well pairs are matched
The breakdown of flex over the lifespan of a ski

Below are some examples of different flex profiles taken on the Signature Flex Tester:

Soft Cold Profile: Long smooth contact zones with a shorter wheelbase at full skier weight. Minimal pressure, think glass gliding on glass. Minimal tip and tail splay. Peak pressure at full weight occurs on to forward of skier half weight mark.

Hard Track Profile: Shorter contact zones with a long wheelbase at full skier weight. Higher pressure zones, yet smooth transition zones. Minimal tip and tail splay. Peak pressure can occur on, slightly behind, or slightly in front of skier half weight mark.

Wet Snow Profile: Short to medium length contact zones with a short to medium length wheelbase. Average to excessive tip and tail splay… dependent on how wet/soft the snow. Pressure is medium to high with smooth yet abbreviated transitional zones. Peak pressure at full weight occurs behind the skier half weight mark.

Definitions:

Bridge: The open space underfoot that does not make contact. Exception: Classic skis; the bridge will collapse underfoot to make contact, this is how a skier achieves “kick.”

Wheelbase: Bridge length underfoot. Can be measured at any applied load.

Contact zone: The gliding zones of the ski… where pressure is applied to sensors/snow.

Peak Pressure: The highest load seen within a contact zone. Skis with peak pressure exceeding 50 lbs in the tip or tail do not possess great gliding properties. Exception: hard track skis can have upwards of 65 lbs pressure in the tail and still perform incredibly.

Skier half weight mark: The location of the front of the bridge when half skier weight is applied.

Transition Zone: An intermediate zone from contact to no contact. Some of the very best skis in the world have very smooth transitional zones.

Tip/Tail Splay: When the ski is compressed, the tip/tail of the ski open up to reduce contact with snow.