Alessandro is an experienced back country rider and skier whose main haunt is the Dolomites. -ed
This is a descripion of how a snowboard is made, but most of it (especially in terms of structure and shape) also applies to skis. I hope that it will be of interest to riders and also to skiers.
During the last 15 years, the snowboard has evolved rapidly: from the first boards made with an "experimental spirit," with every kind of shape and with artisan's passion, we have moved to industrial production. Now the shapes are very similar within the borders of each specialty, and the materials are also the same. That doesn't mean that there aren't differences in performance between models and factories, but now the competition in the snowboard market is based on details - on small, but always important, differences. So it has become more important to know how a snowboard is made to be able to distinguish between boards.
So how is a snowboard made today?
Consider some basic elements:
Flex: This is the ability of the board to bend; a stiff flex is for a race board and it allows for performance at high speed; a smooth flex is for a beginner board because it is easier to drive the board. How the flex is distributed along the board is very important; a board with varying levels of flex doesn't allow a round turn, unless it's on a specialized board (for example, a real extreme park model has softer flex at the tips, and an alpine race model has a harder tail).
Camber: The camber is the bridge of the board that you can see if you put it on a table: the distance between the table and the center of board defines the camber. In fact, a board isn't flat and usually a high camber means a better responsiveness (but also a more nervous board). Often, race alpine boards have a high camber, while freestyle models have a low camber for an easier slide.
Sidecut: This is the real revolution of snowboards in the snow equipment market. The sidecut radius is the radius of the imaginary circle that you can draw on the side of the board. It measures the difference between the width at the top, center and tail. A deep sidecut, that is a big difference between width at the top, center and tail, allows easier short turns and better carving. A low sidecut instead is good for sliding, and also for huge carving on easy slopes.
To understand the real performance of a board you have to consider the mix of all these three elements: flex, camber and sidecut.
The Core: Usually the core is made with different kinds of wood, stiff and light to make the board flexible and durable, vertically laminated. It's very important that the laminate is vertical so the glue doesn't play too important a role in the performance and also so the board will mantain its characteristics over time.
Another kind of core is the foam core. It's cheaper and easier to produce on a large scale, but it isn't as durable as a wood core. For top performance the foam core has to be reinforced with others materials, such as kevlar. Rossignol makes its skis and boards with a foam core, but with so high a quality level that the race models also have this construction (see my Rossignol 9S description).
Fiberglass: Fiberglass is used over and under the wood or foam core to increase stiffness and keep the board from deforming. Fiberglass is like a woven structure and usually it's "biaxial", but even better is "triaxial" (as in K2 skis and in some alpine race boards), which is stronger.
Poly MDI: This is a polymeric matrix that gives good flexibility over time.
Glues: Adhesive matrix is a glue used to stick the parts of the board together. The epoxy matrix has these characteristics: good shock resistance, light weight and very long maintenance of its rigidity.
The Base: The base is usually made in PE (polietilene) and has a porous structure to retain the wax for many runs. It's very important to always put a layer of hot wax (so the liquid can better penetrate into the pores of the base) on the base of your board, so it will remain in good condition. If you leave the base too dry, the friction on the snow will degrade the performance of your board (this is true especially for alpine boards!). The base can be made with extruded PE or with sintered PE. The extruded base is made with a sort of paper of PE and it's a shorter and cheaper way to do it, but it doesn't give the same absorption of wax that a sintered base has. The other characteristic of an extruded base is that it's easier to carve from a stone, but it's also easier to repair. In the end, I think an extruded base can be the right choice for a freerider or a freestyler who doesn't need high-speed performance.
If you are an alpiner, a sintered base is better; the process to make a sintered base is longer and more expensive, in fact the first step is to make an extruded material, after which it is powdered and finally recompacted in a base. The characteristics of this structure are a better wax hold and stonger resistance to shocks. So the sintered base is faster and more durable.
Very important is the molecular weight of the base: a higher molecular weight (UHMW) means a better absorption of wax and a better overall performance. The graphite base is black and is very faster, so it's often used on race boards.
The Top Sheet: This is the layer you can see over everything else, the external top side. Usually it's made in flacee or in ABS, both very resistant materials, very hard to cut.
Sidewalls: These are the narrow sides between top sheet and base. The materials are polymer MDI or PE reinforced with fenolo. The strength of this element is very important because a broken sidewall can allow water to get inside the core.
The Edge: The edge is the metal strip around the board that allows a good hold on ice and protects the corners (the first boards, designed for use only in powder, didn't have edges!). Usually the metal strip is made of steel (Rockwell 48). Between edge and sidewall there's a dampening (often made of rubber) to absorb the vibrations and the shocks coming from under the edge.
Tip and Tail Protection: Usually this is an aluminum plate on the tip and tail to protect the edge from rocks and other shocks. It's not used on all boards and I advise you to put a plastic or rubber protector on the tip if your board doesen't have one.
The internal structure of boards, as with the structure of skis, is different across models and factories, so it's hard to describe in detail (and I'm not rich enough to buy all the models and break them to look inside!). But it's possible to identify three general kinds:
Sandwich: This is the most popular way to make boards and skis. The parts (core, side walls and top sheet) are divided by and stuck together with glue.
Cap: The top sheet continues down the sides to cover them for a better look and an easier method of construction. In my opinion, the performance doesn't improve with this system because it's only a cosmetic effect.
Monocoque: There's a theoretical advantage with a real monocoque system that allows forces to be transferred to the edges better than the sandwich structure. This structure is not widely used because it's really expensive and because a cap system can look similar. But in reality the difference is very big (a real monocoque system is used in Salomon skis).
In snowboard the shape is very important and the differences are greater than between skis; during the last two seasons many ski factories have started to look at snowboard shapes, especially at sidecuts, to introduce something new to the ski world (as in carving or parabolic skis). So in my opinion, the snowboard industry is ahead of the ski industry.
What kind of shape to use is the first question you have to ask yourself when you start snowboarding. If you are a beginner I hope this description helps you. We can reduce the many different shapes to six fundamental ones:
Symmetrical Alpine: This is the shape of most alpine boards. Usually it's narrow, expecially in the center, the forward tip is short and low (for good performance, without vibration at high speeds), the tail is very short, flat and sometimes there's none at all. These boards are designed for speed and stability for an alpine style on packed snow on trails/pistes. The flex must be stiff on race models (expecially at the tail), medium on alpine freeriding models.
The sidecut can vary a lot: for a slalom board the sidecut needs to be very short for very closed turns; for lovers of huge turns a larger sidecut is better, as in a GS model. Obviously a race board is more narrow and stiff than a freeriding one (it can reach 17 cm at the centre), so it's faster to move from one side edge to the other. Also, a racer uses a higher angle on bindings and goes at higher speeds.
If you are a beginner my advice is to avoid the race boards because with them you must always be able to carve turns - it's very hard to do a slide turn with this kind of board.
The bindings for this kind of shape are hard, but if you are a lover of soft boots you can use the non-race models with 3-strap soft bindings.
Asymmetrical Alpine: The asymmetrical boards have two different sidecuts on the front side and back side, with two different lengths and edge positions. The use of this board is similar to the symmetrical use, but this shape allows a better anticipation of the turn especially in slalom; so this type of board is adapted to tracks with closed turns when it's important to mantain a good line before the gate. I think that this shape can also give better performance in agressive alpine freeriding and that the reason why the factories are making this shape only in the race models is that there's an incompatibility between regular and goofy and there are some problems with the stocks (in Europe only in 1994 quite an half of board production are asymetrical, 80% of alpine models). Often the center is larger than in symetrical boards, so you can use lower angles (see Freinademetz foots!) than with symmetrical boards. Usually the sidecut is small (7-9 mt), adapted to SL race, and because it's easier to make the two sides different with this shape.
Freeriding: A freeriding board is usually used with soft bindings, giving good performance on pistes and in powder and allowing some easy maneuvres on jumps - in short an all-around board. Note that I didn't say an entry level board, because there are many high-level models that have these characteristics (Burton Supermodel, K2 Ginsu, Sims Soulcarve...).
This kind of board mixes the characteristics of alpine and freestyle boards together: they are large, but with a good sidecut (7.5-9.5 mt), not too stiff, but without "park" tips. The nose must be long and high (for better floatation), usually the stance is 1-3 cm back. Today almost all models are symetrical, and an easy shape can be good expecially if you prefer to ride on-piste.
You can use it with a low-medium binding angle (5-35°) because the center is not too narrow, but I think that an angle that is not too low offers you a better style of riding. The length has to be medium-long (for guys 180 cm tall and weighing 75 kg my advice is a 158-163 board) for good floating in fresh snow and to carve well on-piste.
Freestyle: I put all the freesyle models in one category, but I'd have to divide them into half pipe, park and freestyle all around. Generally these boards are short (140-156 cm) and large (to allow very low angles) for use in maneuvres and on jumps. Good advice (not mine, I'm not a freestyler, but of my expert friends) is to avoid the extreme boards if you aren't a champ, because their use is too specialized and it'll be hard to improve your style (have you ever tried to carve with a 145 cm park board?). A board that is too short doesn't run well inside the pipe and it'll be harder to increase the speed between the walls, so it'll be harder to do a high jump. The sidecut has to be good in a HP board but not very deep in park boards - in a park you have to slide and do little maneuvres, while in a pipe it's important to be able to drive your board without too much heeling.
The flex is important and, together with the sidecut, makes the difference between HP and park boards: with a park board it's stiff in the center (between the feet) and softer at the tips, while for the half pipe it's better to have medium flex across the entire length of the board.
Longboard: A longboard is similar to the freeride models, but longer (170-185 cm) for good performace in deep powder snow. You have to use this models with softboots for a better sense of touch. It's a good choice if you love backcountry, above all if you usually ride at a resort with a lot of soft snow. If it's hard to find these conditions at your resort, a better solution is a freeriding board of 160-170 cm, because on medium-deep snow or in crusty snow a real longboard will be too heavy and hard to drive. The sidecut of these boards is not so important (for performance in powder) as in other models and usually is about 10 mt. Sometimes a longboard can substitute for a freeride model for real heavy riders.
Swallow Tails: This is a very charming type of board, because it reminds me of the first era of snowboarding, the spectacular video "Apocalypse Now", with the great Regis Roland followed by a troupe of skiers and monoskiers on huge slopes.
This shape is unique and it's likely that, if you aren't an old rider, you've never seen one. The boards are usually very long and have a tail like that of a swallow to allow very good floatation on deep-deep powder at the highest speeds. So with these models you can make huge and quick turns on fresh snow that you'd never be able to do with others kinds of shapes. I know only a few factories that make these board: Nitro, Freesurf, Winterstick (if I missed someone, send me an e-mail).
I hope you have found this topic interesting. Much of it is only my opinion, and if you have different ideas let me know by e-mail.
Alessandro Casson - firstname.lastname@example.org