Saturday, December 20, 2014

Using 14' Fanatic Falcon Race SUP for Windsurfing

As my wife Rhonda says, I am a notorious "min-maxer" when it comes to choosing and fine-tuning my watersports equipment. I proved this recently by swapping my nearly-new racing paddleboard (a beautiful blue 14' x 26" 404 Carbon Pintail Zeedonk) for a different model (a beautiful red 14' x 27.25" Fanatic Falcon).

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The Fanatic was on consignment at CGT Kayaks and Paddleboards and I put my Zeedonk on consignment in its place. If you're in the market for a super-lightweight, all-carbon race sup for under $900 you can find my Zeedonk at CGT. Say you saw it on my blog and they might give you a discount. Here is why I did the switch:

1. I wanted to put a mast-track in the race SUP to mount a windsurfing sail, but I wasn't sure the 10 kg Zeedonk would hold up to the extra abuse it would take in windsurfing mode. The Fanatic is a few kg heavier with a thicker skin more like a standard windsurf, so I figured it would be a safer bet for windsuring use.
2. The noses on the two boards are different. The piercing bow of the Zeedonk works really well for paddling in flat water, but I could imagine it being tricky to negotiate through chop at higher windsurfing speeds. In contrast, the bow on the Fanatic is blunt and upturned, which I figured would make it more "self-trimming" in rough water. (Both boards are supposed to be good for open-ocean "downwinder" paddling and "catching bumps," but I think the Zeedonk takes a more active approach to fore-aft trim when doing that.)
3. When I borrowed the Fanatic for a test-paddle in the Imperial River I found that it was only a little slower than the Zeedonk. That was important, because I didn't want to totally sacrifice my hopes of keeping up with the faster SUP racers in the CGT race series this year.

So far I've been quite happy with the Fanatic Falcon. After pushing myself through some more training runs on the Imperial River, trying a new fin, and adjusting to the board's different style, I've got my course times down to where they were on the Zeedonk. The board is definitely an unusual shape, but it works. The bulbous nose is its most notable feature.

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The nose is supposed to help it bob over waves and chop that it hits at a straight-on or side-on angle, and help prevent it from "pearling" under the water when riding down a wave. I paddled the board one time in choppy waves on the Gulf of Mexico. Though it was a lot less stable and less maneuverable than my Exocet WindSUP and Angulo Surfa, it was pretty powerful for catching waves and getting long, fast rides.

Balancing out the bulbous nose is a long-tapered, narrow tail with the fin set unusually far forward. This makes the overall outline of the board a teardrop shape, like the cross-section of a fin. There's minimal wake behind the board when in motion which implies minimal turbulent drag.

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The weird straps on the front of the board are like suitcase handles for when you're running the board into or out of the water at the start or finish of a paddle race from the beach. I'm not sure I'll ever use them when racing, but they came in handy as tie-down points when I improvised a windsurf sail attachment system for testing purposes. (I wanted to see roughly if the board was sailable before I put any permanent holes in it.)

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For the improvised system I taped a foam block to the bottom of a universal joint so that it could rest on the deck of the board without denting it. Then I tied the universal joint in place with a line to each of the straps, and a line to a little block of wood that I wedged into the recessed carry handle of the board. The carry handle is about in the middle of the board, and I assumed that the mast base would need to be just a bit in front of that.

When I got the board to the beach to test it with the jury-rigged sail attachment it was windier than I had expected; about 10-15 mph with some chop on the Gulf of Mexico. I rigged a 6.4 sail and took off like a shot. The board definitely accelerates quickly and goes fast in a semi-planing mode. In gusts it would get into fully-planing mode, but with a rooster tail of spray behind the tail, indicating a less than optimal pattern of water release from the unusual tail. The board handled the chop very well and went upwind at a steep angle when railed to windward. It took some work to tack, as expected, but it did tack. Jibing was easy because it would keep gliding on the long, voluminous tail even when I stepped far back on the board to make it pivot around. Overall it exceeded my expectations as a windsurf board, so decided to go ahead with the mast track installation.

The first step was to peel away the deck pad where the mast track would go.
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The next step was to route out a hole a little bigger than the mast track. I filled the hole with a sandwich of high density pink insulation foam, with a layer of fiberglass between the two thin slabs of pink foam and a layer of fiberglass and filler between the pink foam and the foam of the board's interior.

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After that cured I routed a hole within the pink foam just big enough for the mast track itself. (I bought the mast track from Roy Massey at Ace Performer.) The next day I put the mast track itself in, in a manner similar to that used for the pink foam. The final phase was to fair the excess fiberglass and epoxy off the top of the mast track and lay three layers of fiberglass over the area, overlapping with the mast track, pink foam, and some of the original decking of the board. I topped it all off with the piece of deck padding that I'd saved so it will look good less conspicuous.

I'm now on vacation at my folks house in North Carolina, but I'm looking forward to testing the real mast track when I get home in the new year. I'm curious how the board will work in really light conditions with an 8.0 or 9.5 sail, as sort of a poor-man's Starboard Serenity / K15.

In other news, my dog gave me a scare the other day when she fell off the back of my WindSUP and took a moment to pop back up to the surface, swimming poorly. To be safe we're going to have her wear this lifejacket from now on. I think she looks good in it.

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Saturday, December 6, 2014

Cool Way to Measure Surface Area of a SUP Paddle Blade

I've been enjoying flat-water standup paddleboarding a lot since doing some informal races this fall and buying a 14' race SUP a few weeks ago. A big part of the enjoyment is striving to go faster. The three main ways to do that seem to be, 1) paddling harder, 2) getting more fit, 3) using better equipment, and 4) developing better technique. I've noticed definite improvements that I can attribute to 1, 2, and 3. Changes in technique have probably had some effect, too, but it has been hard for me to distinguish those effects from the others.

Anyway, as I was geeking out reading about SUP gear and techniques online, I came across some guidelines for what size paddle blade you should use. It makes sense that there would be an optimal size for paddle blades, since a very small blade wouldn't catch enough water to push you forward effectively, while a very large blade would make your strokes awkward, slow, and tiring. Body weight seems to be the main determinant of optimal blade size. Since I weigh around 175 pounds / 80 kg I ought to use a paddle blade with an area between 90 and 100 inches squared.

Its a little more complicated than that, though. Apparently there are at least two other things that affect optimal paddle size: your strength to weight ratio and the length of the race you'll be paddling in. If you're super strong for your weight, like a wrestler or a gymnast, then you can benefit from maybe a 10% or so bigger paddle blade than someone your weight would normally use. If you're doing a short "sprint" race then you might also benefit from a bigger blade. On the other hand, a smaller than normal blade could help in a long-distance race by preventing muscle fatigue. I think I can ignore the race length factor, since the race I do is medium length. Regarding strength to weight ratio, I have no idea how that might be calculated, but I can do about 15 pullups so I'll go out on a limb and say I'm above average in that department. So 100 inches squared would probably be better than 90 inches squared for me.

The only thing is, I bought my paddles a long time ago and I had no idea how big the blades were and whether they were the right size for me or not. Since they're odd shapes with rounded edges it would be hard to figure out their area by normal math and measurement. Fortunately, I'm a scientist, and I realized that I could use the same image analysis software that I use to quantify seagrass blade areas to quantify my paddle blade areas. The software is "ImageJ," a free program that you can download from the US National Institute of Health. I think it was originally developed to help medical doctors measure the size of suspicious moles, etc. It takes a little fiddling to figure out all the features of ImageJ, but the basic method I used to measure my paddle blade areas is this:

1. Put the paddles on a flat surface with an even color that contrasts sharply with the color of the paddles.
2. Lay a ruler or other object of known size next to the paddles.
3. Hold a camera steady and level above the paddles and take a picture.
4. Shrink the file size a bit so ImageJ can manage the picture.
5. Open the picture in ImageJ.
6. Use the line tool to trace 0 - 12 inches on the ruler, and use "Analyze, Set Scale" to set that scale at 12 inches.
7. Use the "Adjust, Color Threshold" menu to turn the image to black and white, and twiddle the levels so that the paddles show up as a simple block color on a blank background.
8. Use the paintbrush tool to cut off the heads of the paddles where they meet the shaft, and fix any gaps or spillovers in the paddle shapes.
9. Use the magic wand tool to select a paddle head, and then use "Analyze, Measure" to get its area, which will be in inches squared.

Original image-
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Processing image in ImageJ-
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I found that my Angulo carbon fiber paddle head is 97.2 inches squared, and that my cheap aluminum and plastic paddle head is 106.8 inches squared. It will be hard to make a fair comparison of the two paddles since the aluminum one is about twice as heavy, but I'll give the big one a try on the race course to see if it seems like the extra size is in any way helpful.