Gavin Upson of 1-DA Shapes finishing up some of his rails.

Gavin Upson of 1-DA Shapes finishing up some of his rails.

The Inertia

There are so many factors that go into how a board will perform, including looking at the surfer. The big factors, however, are related to the simple outline of the board. Essentially the Nose, Rails and the Tail, and how they are linked together. And while each section plays a pivotal role in how a surfboard is going to perform, it is the combination of the three that can mean a magic board or a dud.

The Nose:

The Nose of your board is essentially the first third of the board which blends into its midsection. When measurements are taken for nose width, they are taken at 12 inches down from the tip. The general outline (shape) of the nose plays a lot into how a board paddles and catches waves. The wider or rounder a nose, the more surface area you have in the front 1/3rd of the board, allowing the front end to stay higher up on the water while paddling. This is usually ideal for small wave grovelers, mid length, and long boards, helping to glide you into smaller or softer waves.

The other end of the spectrum would be a pointier nose like those found on high performance short boards. This type of nose is all about the performance of the board while surfing as it doesn’t help much when paddling into waves, other than taking late drops. The pointy nose helps add curve to the overall rail line of the board, allowing the board to fit in the pocket of a hollow wave better and helps keep the nose from sticking in the water (pearling) when coming out of big turns. Another added bonus of a pointier nose is the ability to duck dive easier as there is not as much foam to push under the water when diving beneath a wave.

From left to right: the Panda Doinker Egg, the Hypto Krypto by Haydenshapes and the Mad Cat by SUPERBrand showing how different nose shapes effect performance.

From left to right: the Panda Doinker Egg, the Hypto Krypto by Haydenshapes and the Mad Cat by SUPERBrand showing how different nose shapes effect performance.

The Rails:

The rails of a surfboard play a huge roll in how your that board will perform. The rails span the whole length of the board, from tip to tail, so therefore they almost require more attention to detail than other areas of the board when being shaped. There are many terms related to the different types of rails, and unlimited combinations on how they can be blended.


In its simplest form, every surfboard will fall into one of two categories; the Soft Rail or the Hard Rail, which in turn can be broken down to a Full Rail or a Tapered Rail. Essentially you can have a “full soft rail” or “tapered soft rail”, “full hard rail” or “tapered hard rail”. Soft Rails, usually found on longboards, mid-range and blended in to fish and small wave grovelers, are a round full rail of various foils. They provide more stability and are a more forgiving rail to surf, especially in smaller gutless surf.

Hard Rails, found on performance surfboards, as well as blended into many fish, small wave boards and some mid-length, have a hard edge at a certain point around the curve of the rail towards the underside of the board. The hard edge helps bite into the face of the wave giving you more hold in more critical surf, as well as respond better through turns.

Hard rails vs soft rails.

Hard rails vs soft rails.

In either one of these rails, soft or hard, a fuller rail will provide more buoyancy, which in turn relates to drive or projection when coming out of turns, as well as stability and ease of paddling. A more tapered rail is easier to sink into the water, therefore they are nice and quick when coming into turns and going rail to rail, but they lack the drive when coming out of turns. They also tend to be less forgiving to the surfer as it is easy to accidentally dip your rail in the wave when you didn’t mean to.


And finally, we get into the general foil of your rail. Again, the foil of rails can really be unlimited, but a few general trusted foils are the 50/50, a 60/40 and a 80/20 foil. These relate to where the apex of the rail is around the curve.

The 50/50 rail is usually blended with a soft rail, and can be found on many traditional style longboards. 60/40 rails are turned down a little so the apex is found somewhere between the middle and the bottom of the rail. You can find this blended into both soft and hard rails, and are a great option for fun-boards and smaller wave grovelers and fish’s. They are the perfect blend of stability and maneuverability. And the 80/20 rail takes that apex even lower towards the bottom of the board. Usually found on high performance boards and many times combine with a hard edge (hard rail). Made for maneuverability going rail to rail and through turns, etc.

Different foils help your rail bite into the wave for better performance.

Different foils help your rail bite into the wave for better performance.

There are endless combinations of the above descriptions that can be blending into any board depending on the intentions of the shaper. And all the while the shaper has to take into consideration the overall length of the rail line in the water. A longer, straighter rail line equals more speed, whereas a curved rail will increase maneuverability. It is finding the happy balance of all these choices that makes shaping the rail one of the most crucial elements in the shaping process.

Rails and tails combining with a double wing on Chemistry Surfboard’s Wide J 6 model.

Rails and tails combining with a double wing on Chemistry Surfboard’s Wide J 6 model.

The Tail

Last but definitely not least is the tail of your surfboard. As with all elements of shaping surfboards, the possibilities are endless with tails. There are some basic fundamentals though that come into play in all tails. Wider tails are going to give you more stability and float, which equals a faster planing speed. Narrower tails will be easier to roll from rail to rail and will help with holding into a steep faced wave. A rounder tail is going to “hold” the water a little longer, which translates into more hold and control of the board. Harder angles provide release of the water which means a looser, snappy feel to the board. Rounder tails are better for slightly bigger, open face waves with carving potential. Hard angled tails will be a better choice for punchy, or shorter waves where you want to pack in as many snaps as possible.

Essentially your tails can be broken down into 5 or 6 categories, but remember, there are endless combinations of these categories that can be blended together. The basic surfboard tails are the squash tail, square tail, round tail, pin tail, swallow tail and the asymmetric tail. Your squash tail is one of the most common tails found on shortboards. The squarer back end with rounder corners, give you the snappy feel of a square tail (hard corner) with a nice blend of hold and release of water. They also offer the ability to have a little more width in the tail which helps get you through slow sections of the wave. The square tail is similar to the squash, but the harder corners have more release which equals a skatier feeling board. Usually a wider tail as the rail line comes straight down to a hard corner, these tails are great for down the line speed on smaller or weaker sections, and the hard corners act as a pivot point for turning the board. This was a design from early days and not as common today since the squash does all this and more. The round tail is great for slightly bigger days with open faces. The continuous curve helps hold onto the water, giving you more control on bigger or hollow surf. Great for open face carves, they provide plenty of width to give you more lift when it is not as critical of a section.


Just a few of the common tail shape types – there are also variations on each of these.

The pintail is what you will find on many step up boards, and guns, where you may be sitting in the barrel or just flying down the line on steeper, bigger waves. They don’t turn as well, but provide great hold in big  surf.


The swallow tail is great for a small wave boards but don’t count it out when it’s barreling. Usually giving you a wider tail for planing speed, but with two pin tails, it provides great hold in steeper waves. They’re super fun when turning on rail, but harder to transition from rail to rail when trying bust turn after turn.

And finally,there’s the asymmetric tail. An asymmetric tail is where one side of your board has a longer rail line and different shape than the other. More of a combination of two different tail shapes in one board. One side dedicated to better performance on your heel-side, the other dedicated to you toe-side. The concept makes sense as we can’t perform the same when surfing front side to backside. In reality, the qualities of an asymmetric surfboard go beyond just looking at the tail, but it is the most obvious feature. Your total rail line, the foil and the nose, essentially every factor of one side of the board over the other needs to be looked at for the difference in front side to back side surfing.


A nice little half-crest moon tail on a Chemistry Surfboards model in production, The Experimental.


The Breakdown:

Basically, none of these individual factors work independently from one another. Every surfboard has a blend of all of these factors, and there are endless combinations that can be blended together. It is the balance of everything that goes into how a surfboards will perform. There are tried and trusted designs that have become staples in surfboard shapes, but it is experimenting with different blends that keeps surfing fun.

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