ANNOUNCING: NEW Fin Design - SK8
Before we get started this is going to be a rather long blog as it covers a lot of details showing how and why we came up with the design for this new fin.
As many of you know we have been working on a new design called the XLR8, which has been advancing well, but because it started at the end of the winter surf season we were not able to fully complete our testing, particularly with the canard template. In the meantime, we have been refining the canard fin design from that series. Some of these design changes have previously been documented in this blog.
In the process of these design refinements, we started looking at some of the ideas raised by these refinements and realized that there was potentially a new design lurking within the designs!
We have always been on the lookout for a fin design that would serve as something like a universal canard-style fin. The goal for this fin was a design that positioned the working area of the fin closer to the back fin, but without requiring the front fin boxes to necessarily be moved closer to the back boxes. Our previous design, the WTF, went some ways down this path and did help with this design goal. But we realized what was missing with the WTF was that there was not enough tip area so it could not contribute a lot of drive to the fin, even though the blade does provide drive.
One of the design changes that was made to the XLR8 canard fin was to move the blade further back so that it overhung the back of the base, while also moving the flip in the blade closer to the base of the fin.
This produced the fin design shown in the photo below.
Once we saw this design we instantly liked the shape of the blade of the fin and started to speculate on how we could leverage that shape in a new design. We then looked at the shape of the base of this fin and realized if we extended the base down at an angle we would end up with a design that had a base that was forward, but a blade that was way back. What this meant is that you could have a fin design that had good turning ability but still had drive off the blade while placing that blade closer to the back fin.
This timeline shows how the shape of the fin was derived from the XLR8 canard shape.
This also fixed a common problem with the typical canard fin design where due to the extreme cant angles and the fact that it starts at the base. These fins tend to be ineffective in generating or contributing to the drive produced by the fins, they are strictly limited to helping with directional changes. Because in the new design the blade is higher up and away from the bottom of the board it is in cleaner water making it way more effective. Plus given that the majority of the cant is now located higher up, it becomes engaged later in the turn when the back fin has already started to engage. This makes a huge difference to the drive through the turn.
OK, so the new design meets a lot of the requirements for a canard-style fin. But there was also another rather large set of requirements placed on this design. Let us look at these requirements next.
Many quad setups these days have the two sets of boxes placed fairly far apart, this can have a dramatically negative impact on the effectiveness of selected fins. One of the requirements was that we wanted a fin that would put the working area of the fin further back and closer to the back fin. This would allow fins to work better in a setup that was spread apart. If the back fin was also the larger of the fins it also meant that the front fin would help transition the drive to the back fin. The new design completely satisfies this design goal without requiring any additional changes.
Finally, the last goal was to provide a design that when used in a fin set up that had been optimized for a twinzer it would allow the fins to behave more like a normal quad setup. Typically, twinzers are set up with the boxes fairly close together in order to get a little overlap between the front and back fins. With this new design when it is used as the back fin it puts the working area of the fin further back thereby improving projection and drive.
As can be seen, there are a lot of design goals that are met by this design, largely due to the shape and the placement of the two primary areas of the fin.
NOTE: This design is not necessarily intended to be a complete series of fins with this shape. Instead, the intent is that it serves as a universal utility fin with many of our existing designs, like the XLR8, XTC, or Q2/Q3. What this means for our customers is that they DO NOT need to buy a whole new set of fins, instead they can just buy the appropriate size SK8 to be used with their existing fins. It is also worth mentioning that the versatility and utility of this design will be seriously hampered if you happen to be using the FUTURES fin system as it makes it impossible to switch the fin from front to back due to the different depths of the front and back boxes. To work effectively with that system would require two sets with the two base depths.
TESTING: we have managed to get some testing done with the early swells that have been showing up in Hanalei. Both a SK8-400 twin set and a SK8-500 center fin have been tested. The SK8-400 was tested with the XLR8-500 as the back fin. This setup had previously used the WTF-425 as the front fin. The word is that it has the same feel as the WTF/XLR8 setup but is just better in all ways, faster, smoother, with more drive, and tighter turns! The thruster setup was ridden with the XLR8-500 as the side fins and the SK8-500 CTR as the center fin. Nothing but good vibes from this setup on a bigger board.
Where do we go from here!
Testing, testing, and more testing!
We are also pursuing a regular center fin design based on this general shape as it has a set of characteristics that would make an ideal center fin. The first of these are being made and will be tested in the coming weeks and months.
Stay tuned we are very excited about this design and hope to provide a lot more feedback on them over the coming months!