Maybe you have heard your local shaper mention the term a stringer. But do you exactly know what a surfboard stinger is and what purpose it has?
A surfboard stinger is a thin piece of wood that runs down the center of a surfboard in a vertical line from nose to tail. It separates the polyurethane foam blank into two and adds rigidity to the construction.
The purpose of the surf stringer is to add stiffness to the surfboard, so it stays flexible without losings its shape or breaking under pressure.
Surfboard stingers are made in different materials and designs, depending on the surfboard type and the preference of the manufacturer. But the end goal is the same, to add stiffness to the surfboard to prevent it from breaking and allow it to flex without losing its shape.
Not all board constructions include a stringer, but most of the traditional and commonly used surfboard types do.
The ones that don’t use a surf stringer are built in materials that provide enough strength and stiffness to make the stringer redundant. We often see this construction in high-performance epoxy and carbon surfboards. The epoxy resin and carbon material are stronger than regular polyester resin, which makes it possible to omit the surfboard stringer. The benefit of this is to create a surfboard that has a higher level of flexibility which is preferred by pro athletes when doing high-performance maneuvers, turns, and airs.
The function of a surf stringer
The function of a surf stringer is to keep flexibility in the surfboard but add enough strength to prevent it from losing its shape. The stringer will make the board more solid and durable, so it’s able to absorb and resist any pressure and impact that occurs during a surf session.
When performing turns on your board or pumping to generate speed, you’re compressing the surfboard and bending the stringer. The stringer will then flex and use its strength to project back into its form, which generates momentum and speed to your maneuver.
Surf stringer materials and construction
The most common material used for surfboard stringers is wood, and several types are suitable for the purpose.
The best wood species for surfboard stringers are cedar, redwood, western red cedar, balsa, basswood, engelmann spruce, birch, and plywood. Balsa is the most commonly used type due to its qualities of being super lightweight and durable.
The thickness of the stringer is determined by the size of the surfboard. A thin stringer is perfect for shortboards, where more flex is needed, while a thicker stringer adds more stiffness, which better suits a longboard.
Shortboards and funboards up to a length of 7’3” usually feature a 3/16” wide stringer, while your typical longboard feature a wider stringer of 3/8 or more”.
The rule is simple; The bigger the surfboard, the thicker the surf stringer.
The typical PU-surfboard construction uses a polyurethane foam blank. To begin with, the foam blank comes in a rectangular shape, in the length of the preferred surfboard demissions. It then gets split in a vertical line down the middle. From here, the stringer gets glued to the center before the two foam blanks are compressed back together. After this process, the foam blank is ready for the shaper, who will form the blank into its preferred surfboard shape.
Double- and triple stringer surfboards
Surf stringer layouts can come in different configurations, but the most common construction features a single-center stringer.
Some constructions use a double- or triple stringer design to add more stiffness to the board; this is most common in surfboards like longboards and guns. The design and construction of the surf stringer will affect how the surfboard performs.
Other surf stringer variations includes:
- Multiple stringers: This construction includes 2- or more stringers in any arrangement.
- Flared: The flared construction features a stinger that begins in the tail or nose and then curves to exit along the rail.
- Wedge: The wedge construction features two stringers that start together at the nose and then separate towards the tail, creating a V-shape and thereby making the wedged aesthetic.
- Parabolic: The parabolic construction features two stringers that are bent and follow the rails of the surfboard.
- T-Band: The term T-Band simply refers to a construction where two or more stringers are being laminated together to create even more strength.