A Simple Guide To Surfboard Design 

A simple guide to surfboard design

Are you looking for a no-nonsense crash course on surfboard design?

From single fins to quad setups, we’ve got you covered with our simple-to-understand guide on what goes into making a board and some of the language shapers use.

So let’s dive into the world of surfboard creation to peel back the layers of glass and see what makes the magic happen.

A simple guide to surfboard design

What Does Each Surfboard Shape Do?

Before you can start getting stuck into hands-on surf design, you need to settle on the right board.

Let’s get a brief overview of some of the many surfboard shapes you can choose from:

  • Shortboards – Refined, shorter boards, perfect for steep, powerful waves.
  • Twin fins  – Shortish surfboards with two fins that help you glide over flatter sections.
  • Longboards – 9ft+ of surfboard that’ll have you catching and gliding along waves in no time.
  • Mini-mals – A compact, smaller-size longboard perfect for beginners.
  • Grovellers – Shorter, wider shortboards great for small or mushy surf.

Additional reading – Head over to our guide on the different types of surfboards to get the full low down on how each board surfs and feels.

Once you’re set on a kind of board, it’s all about getting the right foundations.

What Is A Surfboard Blank?

Before we can start thinking about fins and rockers, we need to start with the critical building block. 

A blank, also known as a foam blank or foam billet, is the foundational material used to shape a board.

Blanks are made of a foam core material like polyurethane (PU) or expanded polystyrene (EPS) foam.

This foam gives surfboards their buoyancy and lightweight properties, helping you to float and glide on the water’s surface.

The blank gets worked by a surfboard shaper to create the desired outline, rocker (the curve from nose to tail), and thickness of the board.

Blanks come in different lengths, widths, and thicknesses for everything from small wave boards to giant longboards.

The Nose Of Your Board

Technically your nose is the part of the board twelve inches below the tip of your surfboard.

A board with a narrow nose is designed for high-performance surfing in large or powerful waves.

A wider nose will give you more stability as you ride along the wave, plus the extra foam means more flotation, which is great when you’re paddling to catch waves.

I would always advise you to stick with a wider nose to help you catch more waves when you’re a beginner.

As you progress, you can start to ride boards with narrower templates before eventually jumping on a high-performance shortboard.

*Pro tip – Grovellers (boards designed for small waves lacking in power) are generally under 6ft, so they tend to pack lots of added foam into the nose for extra paddle power; think the Lost Puddle Jumper or the Channel Islands Average Jo.

Your Stringer

Your stringer is the thin piece of wood you can see running down the length of your surfboard.

It helps your board in two ways:

  • Providing structural strength
  • Allowing your board to flex under pressure

They always used to be balsa wood stringers, but with new technology, we’ve seen everything from stringerless boards to new carbon fibre stingers.

Head to the Channel Islands website to get the full low-down on how Spine Tek is revolutionising small wave surfing.

Your Wide Point

The wide point refers to the widest area on a surfboard, but it’s not always located in the centre.

There are two main types of wide points you need to know about:

  • “forward” wide points
  • “pulled-back” wide points

Forward wide points are pushed closer to the nose of the surfboard and suit front-footed surfing.

Pulled-back wide points are positioned further toward the tail and are a better fit for a back-footed surfer.

To find the wide point on your surfboard, place a ruler or measuring tape across the deck of your board and gently slide it down perpendicular to the stringer.

You’re right in the sweet spot when the ruler reaches its maximum width.

Glassing Your Surfboard

Glassing, or laminating, is the process of applying fibreglass cloth and resin to create a strong and durable outer shell around a blank.

The blank serves as the foundation for the glassing process, which begins with taping off the edges and any areas that shouldn’t be glassed, like fin boxes or leash plugs.

There are a few options for weight and thickness, but the most commonly used are 4-ounce and 6-ounce fibreglass cloths.

The heavier cloth provides more strength but can add weight to the board, while lighter cloth offers increased flex while sacrificing durability. 

Now comes the resin. There are two main types: polyester and epoxy.

Traditional PU (polyester boards) tend to perform better in larger waves and windier conditions but can suffer from easy dings and damage.

Epoxy boards are lighter, stronger and more buoyant, making them perfect for groveler surfboard design.

After the resin, the board gets left to cure in a well-ventilated area to harden and bond, creating that strong, resilient outer shell, ready for you to stomp all over.

*Interesting noteMixing colour into the resin at the glassing stage can create an epic-looking resin tint on your board.

Tail Shapes 

Surfboard tail design comes in all shapes and sizes, from the ever-so-common squash tail to the rarely-seen asymmetrical tail.

It’s a crucial aspect of surfboard design that influences performance and manoeuvrability on the face of the wave.

Here’s a brief overview of some common surfboard tail designs and how they affect your surfing:

  1. Squash Tail: The squash tail features a square or slightly rounded shape, providing a larger surface area for stability and speed. The straighter outline generates more drive and control, making it suitable for a wide range of wave conditions.
  2. Round Tail: The round tail features a smooth, rounded shape that offers a smoother transition from rail to rail, allowing for more fluid turns. It provides added hold and control in larger or steeper waves.
  3. Swallow Tail: The swallow tail resembles the shape of a swallow’s tail with two distinct points at the back. This enhances speed and responsiveness because the water flows through the narrower centre section, reducing drag.
  4. Pin Tail: The pin tail features a narrower tail and tapered shape that comes to a point at the back of the board. This design offers excellent control and holds in larger waves and critical sections. The reduced surface area minimizes drag, allowing the board to smoothly navigate steep drops and barrel sections. 
  5. Fish Tail: The fishtail consists of a wider, split tail shape with a deep swallow-like cut in the middle. This design provides increased planing surface area and improved speed generation. The wider tail enhances stability and paddle power, making it perfect if you surf smaller, mushier waves. 

These are just a few examples of surfboard tails, and I’ve come across a lot of other variations and combinations that shapers use to create unique characteristics.

Rails

There are two types of rail design that play a significant role in surfboard performance.

50/50 rails draw inspiration from older, pre-shortboard styles commonly found on longboards. As the name suggests, these rails feature a symmetrical curve, with the apex or midpoint positioned in the middle of the rail.

This creates a rounded, egg-like shape that sits higher on the water’s surface and without a sharp bottom edge, water can flow more freely out from the board’s underside as you glide down the face of a wave.

While this design offers you buoyancy, it makes manoeuvring your surfboard harder due to the lack of a pronounced edge.

The widely popular “down-turned” rails, commonly seen on modern surfboards, start out resembling 50/50 rails from the nose but undergo a transition at approximately three-quarters down your rail.

This transition introduces a sharper lower edge to accommodate the flat bottom of the tail area.

*Pro tipWhen people talk about harder rails, they’re referring to a quicker transition from 50/50 to “down-turned” as you run your hand down the length of the rail.

The sharp edge continues through into the tail and assists in channelling the water flow from the nose, keeping it beneath the board.

This creates lift as the water interacts with the fins in a more controlled manner. Down-turned rails played a massive part in the progression of our sport, allowing critical snaps and carves in the pocket of the wave.

While both rail types have advantages, down-turned rails are the go-to choice for most modern surfboards because they allow surfers to take on steeper sections and faster waves.

Rocker

Rocker refers to how curved the underside of your board is or, as I like to say, ‘how bendy is your banana’.

The kind of rocker your surfboard has affects how it performs in the water in terms of generating speed, manoeuvrability, and overall control of the board. 

And we’re not just talking about the whole board. There are three kinds of rockers you need to be aware of:

  1. Nose Rocker: A higher nose rocker, with more curvature, helps prevent the board from “pearling” or diving into the water when dropping down steeper sections or takeoffs, but you do sacrifice planing speed and, in turn, paddle speed.
  2. Tail Rocker: More tail rocker facilitates quicker and tighter snaps and cutbacks, but excessive tail rockers can sacrifice speed and stability.
  3. Overall Rocker: The overall rocker of the surfboard influences the board’s manoeuvrability and speed generation. Flat rockers tend to be fast because there is more planing surface. A board with a pronounced rocker is incredibly manoeuvrable but sacrifices that down-the-line speed.

Fins

Surfboard fins change how your board feels underfoot, but so does their positioning on the underside of your board.

Shapers can play with the number and placement of fins to completely change how your board surfs along a wave.

Let’s take a quick look at some of the most common placements and the number of fins:

The Thruster

First invented by Simon Anderson in late 1980, this fin set-up is a weapon of choice for most surfers.

It’s comprised of two side fins and one central fin that help give the board more control and manoeuvrability.

The thruster offers a nice middle ground, and you can surf it in all sorts of different conditions, from onshore beach breaks to pumping reef breaks in Indo.

The Twinnie

The ‘twin’ or ‘twinnie’ ditches the centre fin in favour of two larger side fins.

It doesn’t have the same control as a thruster, but what it loses in manoeuvrability, it makes up for its ability to glide easily over flat sections.

This makes the twin fin a perfect option if your local waves are a bit lacking in size and/or quality.

The Quad

The quad takes the twin fin and doubles up with two additional side fins.

The additional side fins make the quad an absolute rocket down the line.

The GOAT himself, Kelly Slater, will often opt for a quad set-up at Pipeline, where he needs all the speed he can find to squeak out of those picture-perfect barrels.

But as always, you’ll sacrifice a bit of turning ability, and you won’t be able to turn on the rail quite like you would on a high-performance thruster.

*Pro tip Fins placed closer to the tail provide more manoeuvrability and looseness, helping you perform tighter turns. Moving the fins toward the centre provides more drive and stability but sacrifices on your ability to turn your board.

Wrapping Up

It’s important to note that even though the theory behind surfboard design and shaping is fairly straightforward, the reality is not.

Learning how to shape requires a lot of boards under your belt and putting in some serious hard work in the shaping bay.

If you’ve enjoyed this read, then make sure to check out our other fascinating reads on surf lifestyle and culture.