Carving Snowboard design - a primer in the basics

This post is a basic FYI. The best English language site for really learning more about hardboot snowboard carving is

https://forums.alpinesnowboarder.com/

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A snowboard (or ski) carves when the front end of the edge pierces the snow surface enough to start to make a groove that the rest of the edge is able to follow. The edge will track a curve in the snow. At low angles of lateral board tilt the radius of curve will be only slightly smaller than the sidecut radius of the board. The rider is balanced on the base pushing against the snow making up the outside/lateral wall of the groove. As the board is tilted higher on edge the curve created by the flex of the board plays a greater and greater role in the curve of the groove. Above 45 degrees board flex is playing a greater role than sidecut as the base continues to push against the lateral wall of the groove. In theory, at 90 degrees tilt the curve is determined solely by board flex, and sidecut is irrelevant.

The size of the turns that can be carved depends upon both the sidecut and board flex. The ability to hold a carve without edge chatter depends both on board and rider tracking the edge in the groove. The edge can be steered out of the groove by the rider technique, twist out of the groove because of torsional flex, or be bounced out by boot out or vibration.

Rider technique to hold an edge is a separate topic.

Makers of carving skis and boards are forever searching for the sweet spot where sidecut radius, longitudinal flex, torsional resistance, and vibration damping are in harmony. While carving boards are still cambered over most of their length, varying lengths and amounts of tip and tail rocker are also common in modern boards to help turn initiation.

Originally carving snowboards were made with single radius sidecuts, and for a while the boards had assymetric edges to try to centre the edge to the heels and toes of the rider’s angled stance. Assymetric boards have disappeared pretty much apart from custom built boards, while some builders still offer assymetric core flex patterns. Experience has led to better matching of core flex patterns and sidecut radii. Yes, radii!
Sidecuts for the last 15 years have generally become variable along the length of the board, often shorter in the nose, and longer in the mid and tail. Manufacturers have their own proprietary combinations. Measuring the effective edge and the depth of the sidecut at the waist merely produces the average sidecut of your board.

Carving boards made in the last 15 years are increasingly likely to have various exotic materials wrapped around a wood core and bonded with epoxy resin. Titanal alloy, glass, carbon and other exotic fibres and rubber are all used.

Titanal (teet-an-al) is an aluminum alloy with titanium, vanadium, and several other alloy components that give it exceptionally high yield strength and great ability to damp and absorb vibration. Depending upon how the Titanal layer(s) is shaped and placed in the overall laminate it can markedly add longitudinal and torsional stiffness. Used in thicknesses between 0.3mm to 1.2mm, the thicker the layer the more rapidly vibration settles, and the deader the board feels. In snowboards it first appeared in race board construction conferring improved edge hold on firm race courses. It rapidly percolated into freecarve board construction where the improved edge hold and ability to carve through smaller bumps and crud was and is valued.
There are still excellent carving boards made without any Titanal, and some riders who predominantly ride good snow and grooming still appreciate the rebound and responsiveness of a relatively resonant snowboard. For the rest of us carving increasingly variable snow conditions a relatively damped board, probably with Titanal in the build, will improve your carving, reduce fatigue, and increase your carving time and pleasure.

To build basic hardboot carving technique look for a recreational freecarve board built in the last 10-15 years, with a suitable weight range for you. Length should probably be in the range 160-175cm, the longer end for taller adult riders. The board waist is likely to be between 19-22cm and the board will be a little wider where your bindings will be mounted.  Sidecut combinations should probably be ideally 10-12 metres, no longer than 14 metres max, as longer than this will make it hard to carve a turn tightly enough on typical resort Beginner and Intermediate runs. And these runs will make you go plenty fast enough. Snowboards rapidly slide scary fast when you don’t skid your turns!

If you buy an older board then your progress may well be slower and achieving consistent carved turns will need a more advanced technique.

Beginners don’t need isolation plates.
Around the same time Titanal was making its presence felt in dealing with vibration and board torsion, an Austrian racer, Benjamin Karl, started winning giant slalom and slalom races with an aluminium plate system under his feet. The underlying concept was rapidly copied, improved, and has evolved. Modern isolation plate systems favoured by current FIS World Cup racers (AllFlex and variants) move the effective attachment points of rider to board further apart, increasing the length of board edge under direct control of the rider and markedly improving mid-section torsion resistance. The extra mass damps vibration and the hinged attachment points isolate the rider further from bumps and ruts in the course. Modern race boards are designed to be used with a plate and are built with necessary mounting inserts. While you won’t win an Olympic snowboard giant slalom medal without one, isolation plates enjoyed only a short vogue with recreational riders before many decided that the extra weight, complexity and cost wasn’t worth it, especially given the advances in design and construction of modern carving boards described above.

Personally I have built and ridden my own hinged isolation plate design and ridden other commercial designs in the past and I was an advocate for their use. But my new boards (with Titanal) since 2017 don’t need a plate to be brilliant carvers in variable conditions.