KENALU ELITE STAND UP PADDLES
What's better about KeNalu Stand Up Paddles? Well, our intent when we designed them was to make EVERYTHING better. Because when something is simple, everything matters.
What's simpler than a paddle?
You can judge for yourself how well we accomplished our goal, but let's look at what we did.
Most paddle blades are joined to the shaft by means of a "frog", which means the blade narrows into a tube that the shaft slides into–like a garden tool. This frog construction is inherently weak because the tube has to be hollow for the shaft to fit inside it, so the only way to reinforce it is to make it thicker and therefore heavier. This hollow element comes at the worst possible time–when the blade is changing radically in cross section, which means the stresses are complex and are focused in all the worst places.
Frog construction also leads to a lot of stress risers–areas for stress to concentrate. It's no surprise that SUP paddles generally break at the stress risers. By designing a paddle with flowing contours we gain numerous benefits, not the least of which is uncompromised structural strength. The contours also make our paddle blades stiffer in all dimensions and enhance the hydrodynamic characteristics as we'll discuss later
The result is a very light blade that is much stronger than it would be with a "frog" design. It is also, of course, very pretty. As usual, good design has it's own intrinsic beauty.
Using that structural advantage we were able to make paddles that are the lightest on the market, and paddle blades that are extremely light, which reduces the all-important swing weight.
Our Elite blades are made in a heat press in precision aluminum molds. The mold finish is so precise that the blades come out of the mold finished except for trim. There is no clear-coat on a KeNalu Elite blade. This is the best molding approach available. It is time consuming, technically difficult, and results in a high reject rate (about 20 percent) but the end result is the lightest, strongest, most precise paddle blade available.
Our shafts are made of prepreg 3K Twill Carbon Fiber in a smaller diameter than is typical and are tapered. This gives a controlled flex between the upper and lower hands–right where you want it for reducing shoulder shock. Our shafts are formed on a precision mandrel with a compression process that leaves a fine “sharkskin” texture on the surface. We angle the edge of the sharkskin so your hand slides down the shaft without resistance, but when you pull up in a stroke the texture gives a firm grip. The grip level can be adjusted with light sanding.
At the handle end the first six inches is not tapered, so the shaft can be cut to size without making the handle loose. After 6 inches the shaft tapers a little over .002" per inch, so the shafts can be cut about twelve inches before the clearance becomes excessive. We've tested our standard handles in shafts cut by twenty inches, and they work fine, but the joint between the shaft edge and the bevel of the handle is stepped and just not as neat as we like. So we have "fat" versions of our handles. If you're going to cut a shaft more than 12 inches let us know and we'll make sure you get one of these special handles.
The bottom six inches of the shaft has an extra layer of carbon fiber to increase strength of the joint. It might seem that the shaft has the same problem as a frog design–no way to reinforce it except for adding material (and in fact we do add a little)–but the strength of a shaft isn't compromised by changes in cross section.
We selected the flex levels of our shafts carefully:
Our 100Flex shaft bends mostly between the upper and lower hand. This gives some cushion to the upper hand without compromising paddle response.
Our 90Flex shaft bends a little more and also flexes below the lower hand. If your elbow or shoulder joints are compromised the 90 flex will smooth out power application and give your joints more cushion.
Our 60Flex shaft is intended mostly for surfing, though there are some racers who appreciate the smoothly extended power application the 60Flex offers. Power surfers who like to really lean on a paddle and have the blade flatten, or who like a catapult launch into waves appreciate this design. It's a little heavier shaft and it's correspondingly stronger.
Most paddles are put together with permanent epoxy. If you cut the length incorrectly it's a big hassle to try to fix it. If you break a component the entire paddle is probably junk.
KeNalu paddles are designed to be assembled with hot glue. You can take them completely apart with a hairdryer or heat gun. You can't simply choose to use hot glue, you have to design the paddle to have enough structural integrity that the contribution of strength from the glue isn't important. And you have to design the pieces to accommodate the characteristics of the glue. For example, all our ferrules are oval shaped. When the parts are glued together the oval cross-section inside the perfectly round shaft creates a gap for the glue to fill which helps them resist torque and ensures the parts stay put.
The oval shape of the ferrule shaft forms a "key" of the hot glue that resists turning the ferrule inside the shaft
Hot glue offers lots of adjustment benefits, for example, with our Extended Ergo-T handle you can change the length of your paddle by six inches with just a hairdryer. We're coming out with a multi-piece travel paddle that's exactly the same as our Elite and xTuf versions. You can disassemble it with a hairdryer but when it's assembled there is no shake or wiggle–the joints are rigid–and the weight is only 50 grams more than our standard paddles.
Once we had a basic design we started work on analyzing and refining it. We analyzed blade wobble and vibration on many test paddles, using digital data recording and high speed underwater video.
The "Paddle Pod" we designed and built to do this testing snaps onto a paddle to record data.
The Paddle Pod records acceleration in two planes, vibration, position, angle and velocity
Our testing revealed a great deal of information about what generates wobble and flutter in paddles, and we were able to design a sophisticated blade that accentuates the benefits of a good stroke. KeNalu paddles catch quicker, deliver more power in the sweet spot, and release smoothly when paddled properly. They will reward your efforts to learn an efficient and disciplined stroke.
On the popular Stand Up Paddle forum "The Stand Up Zone" there is a remarkable thread titled "Review of the KeNalu Paddle". It's one of the most popular threads on the "Zone". More than 370 replies and more than 25,000 views (updated on 12 Nov 2012: 1,227 replies, and 106,251 views). In all those comments there is not a single negative review. The reviews say the catch is amazing, that the paddle is noiseless, that there is no wobble, no vibration.
One of the common themes is people looking at the KeNalu paddle and looking at the paddle they used to like, and trying to understand what is different about it. They just don't look that different. And that is certainly true. As we said in the beginning, when something is simple, everything matters. The shape of the KeNalu paddle is so subtle that it's almost impossible to photograph.
It's not really hard to understand why these blades are so different with just subtle changes. Water is a very dense medium. Making tiny changes to a surfboard transforms it. A master shapes a board and tunes the rocker, rail foil, rail shape, and bottom contours. He adds V, single or double concave in increments that can be barely seen without careful inspection. The result is a magic carpet for surf. Someone knocks off the same basic shape and it's just dead foam and fiberglass.
Surfboards are very complex compared to paddles. Perhaps someone will instrument one and make incremental improvements to designs that way. But it will be very difficult. Paddles are a simpler challenge. We took the test and measurement approach, and it worked.