Have you ever wondered about how your surfboard or SUP works? The terminology requires a minor encyclopedia and each design element interacts with another element. It can be an incredibly complex issue but if you understand a few basics you should be able to figure out what’s going on. All in all, part of the fun of surfing and SUP is paying attention to your equipment. In this manner, it is truly is akin to a type of meditation.
For the purpose of this article we shall start with the tail or “tailblock”. The tailblock is the portion of the approximately two feet from the tip of the tail. It is an extremely important design element. Much of your pivoting while surfing is done on the tail therefore its “design lines”, volume, and rocker (bottom curve) is crucial. I know this is a mouthful but don’t worry. I will break down each topic point by point.
Tail Design Lines
The Square or Squash tail
Basically there exist three basic outlines of tail and many variations in-between. The first is a square or squash tail. As the name implies, the tail is squarish. A square tail can have rounded off edges or hard boxy angles. These types of tails are used for smaller waves and even slower waves. They are excellent as the square shape retains a wider outline as compared to other tails. A wider tail quite simply has more foam in the tail blocks volume. This equates to flotation and lift which are your absolute allies if the waves are small and slow. If the waves are barreling and huge like Pipeline, excess flotation and lift are actually your enemy as the tail wants to “lift” itself out off the water due to the power and curve of the wave. This is called spinning out. The actual “over-lifting” of the tail causes the fins to disengage from the water and one’s board control is lost. On the other hand, if you are on a small slow wave like Daimond Head or Sanonofre, lift is your ally. When the wave is slow the wider outline of the square or squash tail with its additional foam allows you to keep the boards speed. This translates into velocity that can be used in off the lips, cutbacks and zig zagging (weaving) across flat sections.
The Round tail or Pin Tail
The round tail is as the names implies, a tail that has its end rounded off. This tail can be curvy and look like the end of your thumb. A pin tail is similar yet has different angles. In a pin tail, the lines of the tailblock will usually be be straighter and end in a single defined point.
The round or pin tail have advantageous and disadvantages depending on the type of surf that you wish to ride. This is due to the fact that outline of a round or pin tail has less area than a squash hence less foam. This equates into a tail that settles down into the water more. This extra hold can manifest in two ways. If you are surfing slow rolling waves, the round and especially the pin tail tends to settle in the wave too much and you slow down due to increased friction. Remember that there is usually less surface area in the pin or round tail in the tail block hence less flotation. On the other hand if you are surfing a wave like Pipeline or Jocko’s, you want the tail to settle into the water. If you have a wide squash tail in these waves the excess surface area and foam would lift your fins out of the water and you would lose control (spin out). A pin however anchors your bottom turn, engaging the fins. This then translates in to drive or velocity which can allow you to do big off the lips and other gouges. Pin tails can have a great amount of what surfers call “drive” . Drive can be translated into “force direction” in surfer lingo. Quite literally a “drivey” board responds to the amount of force you put in and goes exactly where you want to go.
The Middle Path: The Swallow
What if you want the best of both worlds? You want the Zip of a squash for the small stuff but the drive of a Pin for the more powerful waves. If you don’t have enough money to buy five boards, each for a specific condition, what do you do?
Ben Aipa figured this out in the mid 70’s along with a few other shapers. God bless them for their solution. Imagine taking a square tail. In your mind place a small triangle in the dead center of the square tail with the point facing the nose. Cut out that triangular piece of foam and you get a swallow tail. What is so ingenious about this you may ask? Firstly you have the surface area of a squash tail which allows your board to be maneuverable in small mushy waves. Secondly you have just created two pin tails. A swallow tail is literally two pin tails! When you put the board on the rail, as in a bottom turn you engage one pin (let us say the right pin). Remember the pin settles into the water and creates drive. Then you come rocketing off the top and tip the board on to the other pin (now the left pin). As there is less foam in a pin, the tail holds in the critical section for your off the lip. If the wave slows down your tail block still has enough surface area to fly across the flat sections. This is my opinion but the swallow manages to engage in all types of surf.
I am always amazed at the capabilities of a swallow tail. I have seen Ben Aipa taking off on 12 foot (24 foot faces) Laniakea on a swallow and absolutely destroying the waves. On the other hand, I won the US Championships in 1 foot Huntington mush on a swallow tail.
It is important to understand that the above are just rough generalizations. I have not even taken into account rocker, board length, hips or templates. Yet this is what makes surfing or SUP surfing great fun. There is an infinite variety of equipment types to ride and you cannot possibly ride all the variations in a lifetime. Better yet, equipment forces you to pay attention and in this manner it is a type of meditation. Let me leave you with this question. What kind of tail do you prefer and why?