I started doing some research today into the various materials that goes into a skiboard and found a wealth of information. What started this was comparing the Summit Maurader 125 vs the Lacroix Carbon 125, with the Maurader using p-tex 4000 vs. Lacroix using p-tex 2000. Therefore, I think it could be helpful to start some threads about the materials used.

This thread is about sidecut:

Sidecut radius:

The sidecut radius is the radius of the approximate circle that defines the board's edge when the board is laid flat on the ground. The sidecut radius is a measure of how tightly the board will want to turn.

Small sidecut radius boards want to make small-radius turns at low speed. If you push them beyond a certain speed, the G-force from the turn will try to push them into making a larger arc, and they won't be able to hold an edge, resulting in a chatter or wash-out. Large sidecut radius boards want to make large radius turns at high speed, and let you cruise big arcs.

They won't start to carve until you get them up to a certain speed, which means you may need to burn up more terrain when starting down the hill before carving, otherwise you will either tip over or skid out. Smaller sidecut boards are good for crowded slopes where you need to slalom your way around people at lower speed, or for resorts that have narrow runs. Get a large sidecut radius if you want to go fast on a wide run during the weekdays when few people are on the slope.

The actual radius of a carved turn (the decambered radius) is tighter than the sidecut radius and is a function of the sidecut, how high the board is tilted on edge, the stiffness of the board, and the pressure applied by the rider through the binding. You will get a smaller radius turn with a smaller sidecut, higher board edge angle, softer board, and more binding pressure. However, the dominant effects are different depending on how high the board is tilted on edge:

If the board is very high on edge, the stiffness of the board and the binding pressure mostly determine the decambered radius.

If the board is lower on edge, the sidecut radius will primarily determine the decambered radius.

It is possible to muscle a large-sidecut board into a smaller arc, but you can't force a small-sidecut board into a bigger arc. If you get a large sidecut board, you can "grow into it" as you gain more carving skill, by shortening the decambered radius as you get better.

What sidecut is better for ice? A smaller sidecut allows you to carve at a lower speed, but you don't get as much effective edge for edge hold. A larger sidecut forces you to carve at higher speeds, but you get more effective edge. The answer is to use the largest sidecut for your skill level: Advanced carvers can muscle a large sidecut radius board into a small decambered turn radius, bleeding off speed, while using the longer effective edge of the bigger board.

In order to make the board follow a path that is circular when decambered on the snow, the manufacturer often designs the board using a sidecut shape that is not a circle. Which means the sidecut radius changes along the length of the board, using one of several methods:

Using a mathematical curve: Conic sections, Quadratic, Elliptical, Parabolic, etc. The average radius of the sidecut curve is different at different points on the board, and determines how the nose, tail, and center of the board hook up with the snow.

Using a progressive sidecut that starts out larger near the nose (to make it easy to enter turns), then changes to a smaller radius near the tail (to provide acceleration, like a slingshot).

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Sidecut Depth:

The distance that the sidecut intrudes into the board, measured from a line connecting the widest point at the tip and tail to the deepest point on the sidecut. Greater sidecut depth (smaller sidecut radius on a larger board) results in a board that is more hooky. There is sometimes ambiguity when people use the term "sidecut" without a qualifier, since they could be referring to either sidecut depth or sidecut radius.

This thread is about sidecut:

Sidecut radius:

The sidecut radius is the radius of the approximate circle that defines the board's edge when the board is laid flat on the ground. The sidecut radius is a measure of how tightly the board will want to turn.

Small sidecut radius boards want to make small-radius turns at low speed. If you push them beyond a certain speed, the G-force from the turn will try to push them into making a larger arc, and they won't be able to hold an edge, resulting in a chatter or wash-out. Large sidecut radius boards want to make large radius turns at high speed, and let you cruise big arcs.

They won't start to carve until you get them up to a certain speed, which means you may need to burn up more terrain when starting down the hill before carving, otherwise you will either tip over or skid out. Smaller sidecut boards are good for crowded slopes where you need to slalom your way around people at lower speed, or for resorts that have narrow runs. Get a large sidecut radius if you want to go fast on a wide run during the weekdays when few people are on the slope.

The actual radius of a carved turn (the decambered radius) is tighter than the sidecut radius and is a function of the sidecut, how high the board is tilted on edge, the stiffness of the board, and the pressure applied by the rider through the binding. You will get a smaller radius turn with a smaller sidecut, higher board edge angle, softer board, and more binding pressure. However, the dominant effects are different depending on how high the board is tilted on edge:

If the board is very high on edge, the stiffness of the board and the binding pressure mostly determine the decambered radius.

If the board is lower on edge, the sidecut radius will primarily determine the decambered radius.

It is possible to muscle a large-sidecut board into a smaller arc, but you can't force a small-sidecut board into a bigger arc. If you get a large sidecut board, you can "grow into it" as you gain more carving skill, by shortening the decambered radius as you get better.

What sidecut is better for ice? A smaller sidecut allows you to carve at a lower speed, but you don't get as much effective edge for edge hold. A larger sidecut forces you to carve at higher speeds, but you get more effective edge. The answer is to use the largest sidecut for your skill level: Advanced carvers can muscle a large sidecut radius board into a small decambered turn radius, bleeding off speed, while using the longer effective edge of the bigger board.

In order to make the board follow a path that is circular when decambered on the snow, the manufacturer often designs the board using a sidecut shape that is not a circle. Which means the sidecut radius changes along the length of the board, using one of several methods:

Using a mathematical curve: Conic sections, Quadratic, Elliptical, Parabolic, etc. The average radius of the sidecut curve is different at different points on the board, and determines how the nose, tail, and center of the board hook up with the snow.

Using a progressive sidecut that starts out larger near the nose (to make it easy to enter turns), then changes to a smaller radius near the tail (to provide acceleration, like a slingshot).

-----------------------

Sidecut Depth:

The distance that the sidecut intrudes into the board, measured from a line connecting the widest point at the tip and tail to the deepest point on the sidecut. Greater sidecut depth (smaller sidecut radius on a larger board) results in a board that is more hooky. There is sometimes ambiguity when people use the term "sidecut" without a qualifier, since they could be referring to either sidecut depth or sidecut radius.

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