GENERAL Technical


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This section will introduce some of the terms we use in describing the design of our fins. As well as technical details on the materials and methodologies used in the construction of the fins.


FLIP TIPS are the term we use for the unique design of the tip extensions added to some of our fins. These tips add significant performance enhancements to the fins.


FLIP TIPS are set at between 14º - 16º angle (outboard) to the blade of the fin, and provide a couple of important attributes to the performance of the fin.

Due to the hollow foils on the inside faces of the fins design that utilize these tips. The addition of the flip tip improves the efficiency of these inside foils. This is accomplished by allowing the hollow foil to extend all the way to the tip. Making the unflipped portion of the fin a lot more efficient.

The tips themselves also have a slight hollow foil on the inside face to improve their efficiency and to better couple with the foil in the blade.

One of the most important attributes of these tips is how they allow the board to transition through turns. If you visualize these fins in use you can see that as the board transitions more to the rail the tips of the engaged fins become more vertical in the water.

Not only does this improve the feel of the fin, but it more importantly helps the board come around during the turn, as it provides some thing to pivot around. All of this is done without losing any speed!

The illustration above shows the WF2-S fin and the shape of the flip tips. These tips do not alter the outline of the fin and are only noticeable when viewed from the front or back.

Very hard to describe how the feel and work but once you try them there is no going back, there is something magical about them!

Currently, as custom fins the Q3 range can be made with the FLIP TIPS, as well as the DS-400, WTF-425 and XTC range (these are all now available in our HRD-KORE fins). The WS2 split keels already feature the FLIP TIPS on the front fin - WF2-S, and are available in HRD-KORE.



Foil Drawing
Foil Drawing

Foils obviously play a crucial role in the design of a fin and can dramatically impact the performance. Most of our foils are loosely based around the NACA 00 series of wing sections that are ideal for fins.


We pay careful attention to the foils used on all our fins. We try to match the best foil for the characteristics of the fin and wherever possible we try to keep the regular foils nice and thick for maximum efficiency.


HANALEI FINS are unique in that we have perfected the use of inner hollow foils on the inside faces of most of our fins. We use these foils to increase performance and efficiency. In many cases we also couple these foils with twists and turns in the trailing edge of the fin to better manage the ejection of water from the foils. These foils have a dramatic impact on the overall performance of our fins, but in particular to the speed!


PHAT FOILS is our name for the thicker foils that are deployed on some of our fin designs. By making the foils a lot thicker the efficiency of the fin is dramatically improved. Plus on fins that also use our FLIP TIP technology the PHAT FOILS allow for a much better transition from the blade of the fin into the tips.

Currently, these foils are only available on our custom fins, but some of the newer designs that will go into production this year will feature these foils.


There are a lot of different fins systems available in the market, many with their own unique style of base. HANALEI FINS supports the three primary bases - GEARBOX (our base is also compatible with ProBox), DUAL TAB, and FUTURES, for side fins, and the REGULAR Base for normal longboard fin boxes.


The GEARBOX base is used in our own fin system GEARBOX, it features a full base for a solid feel and greater strength. The GEARBOX base also features vee notches where the screws land that allow the fin base to be forced down into the box when tightened, creating a compression fit.

The GEARBOX base is also compatible with the ProBox Fin System.


The DUAL TAB base is widely available due to the large number of boards with the twin plugs installed. The DUAL TAB base also fits in the GEARBOX fin box. These bases are designed to break under load and therefore tend not to be very durable, breaking at inopportune times. the other problem with these bases is the tendency to flex in the base instead of the fin, this is due to the narrow interface between the fin base and the box.


The FUTURES fin base is a lot longer than other bases due to the design of their box. Due to the nature of the fin ox design the cant angle is built into the base of the fins instead of into the box. This makes it really complicated making fins for this system, especially if they are custom fins as the can angle has to bee machined into the base of the fin. Fit is critical for these bases as there is no means to tighten them if they are loose.

These bases can also be a lot heaver due to the fact that they are almost double the length of a GEARBOX or DUAL TAB base. This is why you will commonly see these bases heavily machined in order to lighten them up.


The REGULAR base is the standard longboard center fin style base. Designed to fit in most modern center boxes.


RTM molding is one of the most predominant methods for molding fins. It stands for Resin Transfer Molding. The fabrics and core that make up the fin are laid dry into a mold. The mold is then closed and a vacuum is used to draw resin through the mold, wetting out the materials in the process. The use of a vacuum also draws all the air out of the laminate eliminating air bubbles.

RTM molding is a lot more cost effective and less wasteful than the standard method of foiling a fin out of a solid panel of fiberglass. Because a mold is used it also makes it easier to manufacture more complex shapes in a consistent manner.


Fins can be made out of a wide range of materials, but these are some common standard materials, with fiberglass being the most prominent one. RTM molded composite fins use a combination of these materials.


Fiberglass forms the bulk of a fin construction and is applied either side of the core material in our HRD-KORE construction method. The typical fin can have as many as 27 layers of fiberglass to provide strength and some flex.

Custom fins are made out of panels that are built into solid sheets of fiberglass and resin. The number of layers can vary from 30 to 40 layers. This is the standard material for hand foiled fins.

Carbon Fiber
Carbon Fiber

Carbon fiber is very strong and stiff for its weight making it perfect for base stiffening. Employed in the base area of the fin to add stiffness and strength, it is applied to both sides of the fin as an outside layer that is visible in the finished product.

SORIC Fabric
SORIC Fabric

Soric® is a conformable flow media for resin infusion. This product features unique hexagonal flow channels across a carrier sheet that create a steady, even resin front. Forms the core for the fin and reduces weight by reducing the layers of fiberglass needed to construct the fin.

G-10 Fiberglass
G-10 Fiberglass

G-10 glass cloth reinforced epoxy natural is typically a yellowish to light green color. The most versatile all-around laminate grades are continuous glass woven fabric impregnated with an epoxy resin binder. These panels are made under high pressure so there is no air in the panel and the resin to fiber ration is very high. This makes for an incredibly strong panel.

Because these panels are manufactured it makes it a lot simpler for a fin manufacturer as one simply purchases the panels and then cuts fins out of it as needed. The panels are a lot more expensive than a standard fiberglass panel, but worth it for the strength.


We have two primary office locations for HANALEI FINS - Australia and Hawai'i (USA). Contact info is provided below but the preferred contact method is through the CONTACT form on this site.

+61 417 243 592
+1 808 639 5303

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