# The meanings and relationships of common snowboard parameter data

**2017-08-13

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The following data and the relationship between them.

Size of the board，length of the board：the length of the snowboard surface from the head to the end of the board. It can be easily measure by a soft ruler, you just need to go along the surface of the snowboard.

nose length：

tail length：

Contact length and running length: normally, the measurement of these two data will be matched with the following formula.

contact_length = running_length

contact_length = length_the_board - nose_length - tail_length

For the definition of this value, we are based on Burton's definition. Because in the usual design of the snowboard, for the standard Camber, the top of the board plate is the highest point of the board as well as the widest part of the board. That is, as shown above, this is a relatively standard design. But since the emergence of Rocker, the contact length and run length is not necessarily equal. The length of the contact is the surface length of the snowboard between the two widest points which are at both nose and tail of the snowboard. The running length is the distance from the highest point at the end of the board to the nose of the board. The running length is long, so this value is just for reference without great specific practical significance.

Nose width：

Tail width：

Waist width：

Side cut depth：Some brands do not mark the side cut radius of the snowboard, they would use the depth of lateral to represent the size of the side cut. In general, this value should be in line with the following formula:

side cut_depth = (nose_width - waist_width) / 2

The radius of the arc also means the side cut, the side of the arc. Now most of the side shape of snowboards are not round ones. There are many shapes such as multi-radius cut, oval, parabolic, hyperbolic, conic, spiral. So this radius is only an average data which is only for reference, and the side cut radius can only be approximate to the turning radius, and the actual turning radius is different. The actual turning radius should vary depending on the edge angle, the bend speed, the quality of the snowboards, and so on. The derivation formula of the side cut radius can be approximately calculated by the following formula. The specific derivation of the formula is very complicated. I’d not mention it in this article as it is of little significance. The formula is derived from the formula "The Physics of Skiing"

side cut_radius = ( effective_edge_length^2 ) / (8 * side cut_depth)

Effective length, effective access to snow edge length. This value is usually longer than the contact length value. Each brand has a different definition of this value, such as the definition of burton is the length of the snowboard flat contacted with snow.

About this data,some brands directly defined it as the length of the contact. The algorithm of this data is more complex for some other brands, the definition of it is the actual contact length of the edge of the snowboard with the snow.

Since this value is relatively important, I give here a relatively general explanation. But this explanation does not represent the official opinion, the specific explanation of this data is base on the programs which the manufacturers applied. My explanation is only an approximate general explanation, see the figure above, make a tangent line from the vertex of the side cut depth to the both the nose and the tail of the snowboard, the arc length at the edge of the snowboard below the tangent line can be approximated as the effective edge length contacted with the snow.

This is highly related with the warpage of the nose and the tail as well as the shape of the board. But the decisive role is the length of the nose and tail of the snowboard.The smaller these two values are, the greater the relative effective edge length. And the side cut radius lays minimal effect to the effective edge length, but there is one thing we need to pay attention to, that is this area represents the resistance encountered after the snow cut.The larger the area is, the greater the resistance. So,for the snowboards of the same length,the one with large side cut radius actually slides faster than the one with smaller side cut radius.

The calculation formula of this data is more complicated, so I will not list it in this article. Usually, the brands would mark out of the value of this data.

Nose height: the height of the snowboard head, the cock height of the head of the snowboard from the ground. In free-type snowboard field, higher represents better buoyancy. In race snowboard field, this height usually determines the type of the snowboards, Race or Freecarve.

Tail height: the top of the end of the snowboard from the ground. In freestyle snowboard field, usually the height of all-round snowboard head will be greater than the board tail height.Yet for some other freestyle snowboards, the lengths of the nose and tail are usually equal. In the racing field, the height of the tail is usually 0, and there will be more weight at the tail of the snowboard to pressure the snowboards more stably onto the snow.