Edge Control (Part 1)

As a carve-apprentice, I’ve come to realize that power transmission to the board edge doesn’t need to come at the cost of forgiveness. When snow conditions are forgiving, you can easily ride with a foot, boot, binding and board interface so rigid that each twitch of the leg is sent to the board edge. The snow simply forgives you for your mistakes. The same isn’t true when riding un-forgiving snow, such as a racecourse with a rutted and icey apex at the gate. Under these conditions, the rider’s slight leg movements can be amplified into huge mistakes if the interface is too rigid.

Let’s look at the word interface. Webster’s dictionary defines interface as “a surface forming a common boundary between two things”. For snowboarding, there are four things, and these create four distinct interfaces: (1) foot to boot, (2) boot to binding, (3) binding to board and (4) board to snow.

Each of these interfaces will play a part in transmitting the rider’s commands to the snow and relaying the snow’s response back to the rider.

Foot to Boot

Proper fitting boots are essential for board control. If the rider’s foot isn’t properly secured within the shell, foot and lower leg motions are not properly sent through the interface. A boot that is correctly fitted will not only create a solid interface between the rider’s foot and boot, but will also be warm and comfortable. A lot can be said for eliminating distractions on the racecourse and uncomfortable feet are difficult to ignore!

One of the easiest ways to improve boot fit is the use of a heat moldable liner in conjunction with a footbed. Two common heat moldable liners (INTUITION Sports & DeeLuxe) are made from EVA foam and are truly do-it-yourself. More performance gains can be realized by installing off-the-shelf footbeds (Dr. Scholl’s Advantage Sport insoles) but custom orthotics may be necessary for problem feet.

Boot to Binding

For alpine riders there are two types of boot to binding interfaces available. Bail (often referred to as standard) or step-in. The step-in interface connects the boot to the binding via one of three methods (Physics, F.A.S.T. or INTEC™). All of these methods allow the toe of the boot to be set in place, then the heel is secured by metal pins and receiver. This makes a very rigid interface between the boot and binding by not allowing lateral movement of the boot, especially in the heel area.

The standard interface connects the boot by securing it in place with metal bail around the heel, and an ‘over-centre’ lever to secure the toe. This interface is not as rigid as the step-in for to two reasons. First, the wire diameter of the bail and over-centre lever material determines how much flex occurs in the interface. A larger diameter wire bail and metal lever means stiffer interface. Smaller diameter wire bail and plastic lever means more flex, sometimes at the cost of binding failure or breakage.

Second, the heel and toe pad material of the boot will determine how much lateral flex occurs. A heel pad that is made from a relatively hard material results in less lateral flex due to it’s diminished cushioning affect. The opposite is true for heel pads made from soft material.

In order to tune this interface, look for a binding that provides a large diameter bail and a metal over-centre lever that are unlikely to break, then adjust the lateral flex by utilizing a heel pad that is suited to the rider’s weight and ability.

Binding to Board

There are two types of binding to board interfaces. The first is where the rider’s leg commands are passed directly to the board via a solid metal interface. This interface is fine when riding forgiving snow, but is the more rigid of the two interfaces.

The second type cushions the rider’s leg commands from the board through the use of elastomer pads. This type of interface is less rigid and often preferred for unforgiving snow. Probably the best example of this type of interface is the Bomber TD2. Aside from it’s solid construction and fully adjustable lift and cant, the TD2 binding has a distinct advantage over many others. The rider is fully suspended by adjustable (soft, medium, hard) isolation cushions. By selecting the proper cushion (urethane ring), the interface can be tuned to react to the rider’s weight and ability.

What does this mean? First, the rider experiences a smoother ride because less of the chatter, from imperfect snow conditions, makes it’s way through the boot and into the body. Second, the board has better edge hold because it’s allowed to perform as designed by following the contours of the slope without the chattering associated with overly rigid interface. And third, the binding can be utilized by a rider that weighs 50kg (with soft urethane rings) just as easily as a rider that weighs 90kg (with hard urethane rings).

Board to Snow

How the board performs on snow is a discussion for it’s own ‘ARE YOU AN ALPINE SNOWBOARDER?’ article. Stay tuned for that in another edition of “Are You An Alpine Snowboarder?”

– Dave Morgan