Head Constructions

These are but four recipes in the current Head ski cookbook.

One bedrock principle of marketing is to draw public attention to your product’s differentiating feature that delivers a performance, comfort or convenience advantage over the competition. To reach the widest audience, the communication has to be compressed to the point where the “elevator pitch” better not take more than one floor to spit out.

This all but obliges the savvy ski maker to draw the ski shopper’s attention to some readily identifiable detail to which can be attributed a succinct benefit.  In the current market, the feature that’s attracted the most buzz is the translucent honeycomb tip on the bumblebee-colored Rossignol Soul 7.  Never mind that Rossi is hardly the first in recent history to make a see-through tip design – that would be Kästle – nor the first to use honeycomb in its extremities, as has Salomon previously; the latticework in the Soul 7’s Air Tip is pretty, it screams “lightweight!” and it’s easy to ski. Case closed, ski sold.

What makes the Air Tip a particularly clever coup is that it doesn’t actually do much to contribute to the Soul 7’s turn shape; the functional sidecut that’s the dominant factor in turn definition doesn’t continue into the yellow tip and tail sections.  It’s not that the visually appealing extremities don’t contribute anything to the Soul 7’s performance, as it’s axiomatic that a ski is affected by every aspect of its design.  Creating lightweight tip and tail sections would not by itself ensure a successful design; the real magic in this ski lies in its black center section and how well it marries to its bright buffer zones at tip and tail.

The case of the Rossi Air Tip raises an interesting question for the ski buyer: What are a great ski’s defining characteristics and can this knowledge be applied to the business of picking your next ski? To answer this question we shall break it down into several smaller inquiries that together should give us a clearer view of the whole enchilada.  To give this exposition some flow, we’ll look at these issues roughly in the order in which they arose historically.

Is a ski defined by its material make-up?

The first skis were made entirely of wood, so naturally the material’s contribution to the ski’s overall performance was close to 100%. What wood was selected, and how it was laminated, made all the difference in the world.

When metal appeared in the form of aircraft-grade aluminum alloy, it was clear that the new material made a better ski.  Then along came fiberglass and it quickly became the most common structural element used in skis.  No matter how it was used, where it was used, whether it was wet or dry, woven or unidirectional, in torsion box or laminate lay-ups, wet wrap or pre-impregnated, fiberglass was the material that determined a ski’s character.

Since the advent of fiberglass, every high-strength-to-weight-ratio fiber to come out of any NASA-funded laboratory has found its way into a ski.  Almost all have proven far too expensive and, often, too rigid to use as the sole weight-bearing material in a ski.  The one magic material to emerge upon much experimentation was carbon, partly because its use by other industries brought the cost down, and partly because it could be made in any stiffness desired.

For several decades there endured a lively debate over the relative merits of wood core versus milled-foam core skis, as if the cores were the major contributors to the skis’ overall comportment.  (One reason the schism endured so long is that the world’s number one manufacturer at the time was Rossignol, who fancied the cost advantages and consistency of foam.) This quarrel has long since been settled in wood’s favor, although the infatuation with all things light has already led to the use of the lightest possible woods (or the heaviest grasses — take your pick); can some new form of foam be far behind?

One reason the wood vs. foam debate abated was the arrival (in 1989) of the Salomon ski and its monocoque structure, which switched the discussion from core material to how the ski was laid up around it.

Is a ski defined by its construction?

Until Salomon set the ski world on its ear with the instant acceptance of its monocoque story, ski construction fell into two camps: torsion boxes, which wrapped fiberglass around the core on all sides, and laminates, or sandwiches, which stacked layers of glass and/or metal above and below it.  The springy torsion boxes were deemed best for the agility of slalom racing or moguls; laminates were ideal for introducing metal sheets into the mix, which were essential for maintaining edge grip in the speed events.

Once Salomon stirred the pot, how a ski was assembled from its constituent parts became all anyone could think about. Separate sidewalls, once considered humble components made in either soft ABS or stiffer phenolic, now had either to be covered up in a slanted layer of goop or discarded all together.  Suddenly, if you didn’t make a cap ski, you didn’t sell many skis.

This worm has turned entirely since the mid-1990’s, with a stout, tip-to-tail sidewall presumed to transmit the most energy to the edge while a more compliant cap construction will compress under less force.  Today, no one considers the sidewall construction to be the linchpin factor in ski behavior, but it remains a detail worth noting.

The movement that moved monocoque off center stage was called Carving, and for a while in the late ‘90’s if you wanted to sell a ski to the world’s largest ski retail chain, Intersport, it had to be classified as some variety of “Carve” ski, as in Super Carve, Fun Carve or Race Carve.  During this period, a ski was its shape, period.

Is a ski defined by its shape?

Ever since the beginning of the Carving Era skis have been categorized in one way or another according to their shapes.  In the early years of super sidecuts it was the depth of the hourglass shape, calculated as the radius of the sidecut in meters, that indicated its predicted path downhill.  As fat skis grew in popularity and girth, meter radius measurements became less descriptive of a ski’s capabilities than knowing its width at the narrowest point underfoot.

Today we still scrutinize a ski’s shape to decipher its comportment, only now we examine shape on two axes, horizontal (sidecut) and vertical (baseline).  Sidecuts have mutated from the old, 3-point geometry (tip/waist/tail) to a more fungible formula where the widest points are moved closer to the center.

A ski’s baseline has morphed from mimicking an aqueduct’s arch (a quaint configuration still referred to as “camber”) to a handlebar moustache (front and rear rocker with twin tips) to a stretch of front range farmland (flat with a little early rise).

Does all this tweaking of ski shape every which way affect behavior?  You bet it does. A ski is still essentially a weight-displacement device that can be tilted and pressured to change direction. The shape of the device matters.

The most commonly referenced metric in today’s market is waist width. This one number provides the single best clue as to where a ski prefers to travel. The wider the waist, the greater the ski’s predisposition to powder.  (Another adage of ski dimension design is that you can’t fake fat.)

But shape isn’t all that matters.  At the infancy of the shaped ski revolution, the first experimental skis, whether for powder or groomed conditions, were made from elementary constructions.  (This doesn’t include the slight changes in GS ski tip dimensions that presaged the arrival of much deeper, recreational-ski sidecuts.)  That’s why some of the avant-garde models weren’t such great skis, even though the ideas they embodied would re-shape the industry.

So we know that shape alone won’t predict greatness. For a great shape to sing, it must be accompanied by refinements the world’s top manufacturers have been making in flex tuning and vibration damping.

Is a ski defined by its flex and vibration management?

We’re getting closer to the nugget of truth. A ski that can’t be bent or kept in contact with the snow surface can’t be turned, regardless of its shape, construction or componentry.  How readily a ski responds to neck-rein pressure and how much skill and effort it takes to sustain a continuous arc at various speeds are significant factors in deciding if a ski is a good match for the skier.

The two biggest evolutions in how expert skiers negotiate a hill over the past 25 relate directly to the two biggest changes in skis over the same span: skis have become shorter and have many more dimensional varieties in sidecut and baseline.  Without advances in dampening systems that allow shorter edges to feel secure on hard snow and variations in flex profiles to optimize performance in every snow condition yet encountered, skiers wouldn’t have these ultra-adapted tools at their disposal today.

Pressure distribution and vibration control have been pivotal issues since skis were first whittled from wood.  Mastery of these matters has been what’s separated good skis from great ones throughout the modern era of ski design.

The envelope, please.

So what is the most important factor in a ski’s make-up?  The answer is buried back somewhere in our preface: a ski is everything that goes into it,right down to the glue.  Its sidecut, its materials, its construction, its damping methods, its waist width, its baseline, its finish ex-factory, all play a role in what the skier feels on snow.

The driving force behind the last 75 years of ski manufacturing hasn’t been finding new materials (although that’s a close second), creating new shapes or even managing vibration; it’s been the quest to make ten thousand identical pairs of skis.

Put another way, the biggest problem ski manufacturers have faced—and largely faced down—over the past three-quarters of a century wasn’t how to make a great ski, but how to make the same great ski over and over again, with infallible consistency. At the end of the day, how well a manufacturer assembles and finishes a ski has as much to do with its quality as anything that goes in it.