Sunday, August 2, 2015

Maximizing Early Planing on Exocet WindSUP 11'8

A while back I sold my formula windsurfing board. I did it because I wasn't in love with it and because I had too many light-wind watersports options between racing paddleboards, windsurfable paddleboards, and even windsurfable racing paddleboards.

The remaining board that comes closest to filling the early-planing niche of the absent formula board is the Exocet WindSUP 11'8, which is 360 cm long by 80 cm wide, 220 liters volume, and 16 kg (heavy). That is far from the optimal early-planing stats of a formula board (~235 cm long x 100 cm wide, 165 liters, 9 kg), but the WindSUP is not as far behind in planing ability as you might think. With my 9.5 Ezzy Cheetah sail, I could get my formula board "over the hump" to planing in just about 10 knots of wind, whereas on the WindSUP there's a gradual entry to planing between 10 and 12 knots. The type of planing is a little different, though. On a formula board you're really zipping along "riding the fin" and you can go upwind easily. But on the WindSUP, at least with the 44 cm stock fin, you don't have much upwind drive when using a big sail, like the fin is not quite balancing out the weight and pressure of the board and sail so you don't quite get the flying over the water feeling. In my experience the 44 cm fin is plenty for sails up to 8.0 meters squared, but not for the 9.5.

SO, I ordered a 50 cm Hydrotech fin to test with the 9.5 sail. The first time out was one of those frustrating days where the wind was good when I left my house but had sunk to just below the planing threshold by the time I got to the beach. So I didn't plane that time and of course couldn't tell much difference between the new 50 cm fin and the old 44 cm one. Yesterday, though, I got a good session in 10-15 knot winds, and the 50 cm fin really showed its worth. I could put tons of pressure on it with my feet in the outboard footstraps, and translate that pressure into upwind sailing angle. I think it also helped a little bit with early planing and with maintaining a plane through lulls. The next step is to try it with an 11.0 sail to try to find the ultimate early planing limits of the board. :)

Here's the big fin in the board.
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Here you can see the stock 44cm fin and its sheath next to the sheath for the new fin. They say the maximum useful fin size for a board is approximately equal to the width of the board underneath the fin. The old fin was considerably less than that, while the new one is close to right on. Of course, with smaller sails and for waveriding and stuff the WindSUP handles best with smaller fins. The whopper fin is just for early-planing with the biggest sails possible.
 photo 0802151040_zpsjtpz7hkd.jpg

PS- After I got this fin, which I ordered online from Sandy Point Progressive Sports, I realized I probably could have gotten something just as good from the more local Ace Performer shop. Next time I'll try to remember to order from them because I like what they're doing up in Fort Myers, teaching lots of people to windsurf and sup at the Sanibel Causeway, keeping windsurfing somewhat alive in Southwest Florida.

15 comments:

Bryn Kaufman said...

Thanks James for this post. I have the Exocet WindSUP 10' and I am always interested in what to do to plane sooner. In my case I use a 7.5 sail max, so the big fin will probably make some difference, but not as much as with the larger sail.

Planing is an interesting term when applied to these WindSUPs. It starts with a fast glide, and I am not sure how fast one needs to be gliding to consider it planing. On my short board I was never planing unless I was in the foot straps, but I have two WindSUPs and one does not even have straps, so I can't use that definition, and if I would change the straps position on the Exocet I could get in them sooner, but I am not sure that means I am planing any sooner than when I am out of them.

Neville said...

I have the same board and 9.5 sail. Have you sailed it with the larger fin yet? Curious as to the performance.

James Douglass said...

Hi Neville,

Yes, I have sailed it with a larger fin. The results are described in the third paragraph of this blog post.

-James

Ottis Martin said...

I have riden the 11'8'' and love it. I am a bigger guy (about 125kg) and am in the process of purchasing the Kona Mahalo. I want to get my daughter her own step tailed board and was thinking due to the weight/volume ratio the exocet 10' might be a better choice for a lighter rider. She also has riden the 11'8'' and it was the first board she got on plane (she's planed on other smaller boards since). I know a lot of the talk on here centers around teh 11'8'' but I'm wondering if it's mainly because it's all adult men or if the 11'8'' is the best choice for all sizes. I still haven't riden the Mahalo but am looking forward to it soon.

Thanks for any input.

James Douglass said...

Ottis- From everything I've heard, the 10'0 is a great board for smaller riders. Probably better than the 11'8 for people < 75 kg. :) -James

Bryn Kaufman said...

Ottis, I have the 10'. I weigh 70 kg. I can tell you with the dagger board up the board feels a lot smaller than my BIC 10.6 WindSUP. It is an interesting board as it has the feel of riding a smaller board even though it is pretty large. For paddling I prefer the BIC because it is more stable and I like the 3 fin setup so the fins are not a deep if you ride a wave in closer to shore.

For high performance Windsurfing there is no comparison. The Exocet with foot straps just performs in a totally different class.

So if your daughter wants to plane quickly and go fast and knows how to get in the foot straps or wants to learn how, the Exocet 10' is a great choice. If she prefers more mellow light wind sailing with a lot of paddling and wave riding mixed in, the BIC or something else might be a better choice, or even the bigger Exocet for the increased stability.

With the 10' I had the dagger board removed and sewed the rubber shut to prevent water from coming through. I find it much nicer to ride that way, plus the board is lighter and the dagger board slot is a great carrying handle.

Ottis Martin said...

Another quick question. I have taken my board (the Kona Mahalo) wave sailing in small surf (knee to waist high) and light, non-planing wind (8-12kt). I've been using a 7.0 Cheetah sail but have been contemplating getting a 9.5 Hot Sails Super Freak or even another Cheetah to get me through and onto the waves quicker. Is this just way too big for wave sailing? (just cruising down the line not trying to ride too agro) Also, should I use a RDM or standard mast on a sail that big in the waves?

James Douglass said...

Hi Ottis,

I have found a steep drop in the fun factor when trying to wavesail with sails >7.5. The weight and geometry is awkward, especially when dealing with the odd changes in wind angle and apparent wind that you encounter when catching waves in light wind. Plus it's slower to tack, jibe, and uphaul, which means it's easy to get caught in a bad position and break gear. If you like wavesailing, a better investment might be a 7.5 wavesail with a 460 or 490 RDM.

-James

Bryn Kaufman said...

Hi Ottis,

I agree with James. I have waved sailed on my 7.5 and it feels too big. For really light wind wave sailing I prefer my 5.7 Aerotech WindSUP sail. It has the pull to get you on the wave, but once on the wave you kind of forget about it and just focus on surfing the wave. It is really light. With the big sails if you try to turn on the wave I found the back of the sail goes into the water sometimes.

One other observation, 12kt for me is not non-planing. With a 7.5 and my Exocet WindSUP 10 I am planing in the foot straps at 10kts. It might be my light weight 155lbs, or my big 200 Chinook Carbon Boom which gives my sail more shape without hitting the boom.

So you might want to consider how you can lower your planing wind minimum because that will also get you onto the waves faster.

Ottis Martin said...

Thanks James and Bryn. I've got almost a hundred pounds on you Bryn. I find my window for planing is 15kts. with my 10.3 Formula Hot Sail. I stuck my head through the main panel and it's now got a 2 foot long piece of Chinook sail tape holding it together so it's kinda semi-retired. Plus the 3 cambers (with no zipper or velcro access) makes it a nightmare for rigging and de-rigging. I can get planing on my 7.9 NP Diablo in about 17knts. It's way too delicate of a sail to take into the waves, almost 100% mono-film. I believe it was the predecessor to the NP Helium sail, a no cambered free/race sail. I can get planing on that sail it seems just as early as my 9.5 Ezzy Infinity. Not sure if it's because of the lighter weight of the sail, the materials/design of the sails, or the way I'm tuning the sails. The Infinity feels softer and more forgiving than the Diablo or Formula Hot Sail in the gusts. My Ezzy Cheetah 7.0 is my 20-25kt. sail. :O

I'll have to check to see if any of my sails are touching the other side of the boom. I know my Cheetah was because I was filming with a boom mounted GoPro and could see it in the play back. I've switched to using a larger boom on that sail since.

Ottis Martin said...

James, here's a windsurfing/science question for ya...

I've had some classes in physics and wanted to know, when you came up with your windsurf sail calculator, did you develop your own formula or are you using the inverse square law? It seems like it would work once you found a good base point to start from.

Ottis Martin said...

I went sailing yesterday in 10-15 kts. with my Kona Mahalo and 9.5 Ezzy Infinity sail an I paid close attention to the sail and noticed something odd. When sailing with my starboard side windward my sail was touching my boom, but not when I was sailing the other direction. Any ideas what could cause this and how to fix it? My boom is a NP 225-280cm and I am using 20cm of extension for the minimum outhaul of 244cm.

James Douglass said...

Hi Ottis,

I made the calculator based on a formula someone posted on the star-board.com forum ages ago. I believe the formula was the result of empirical curve-fitting rather than any specific laws or theory. I.e., the actual physics relationship is probably a lot more complicated than the equation I used just to fit the data in a simple way. But the simple equation works.

The sail touching just on one side thing can happen if one of your boom cuffs is slipping. It might also have to do with how your outhaul is threaded and tied. Or your boom could be bent. Or the sail could be somewhat asymmetrically foiled, because of which side the battens are sewed in on or something.

-James

Brandon Morrical said...

You've done some great work optimizing all your boards. It's fun to see how you improve on an already great product.

I have an 11'8 WindSUP as well, but last year I got kinda tired of the looks. And from what it looks like of yours as well, the paint faded from purple to a bluish, and I had few other scuffs and such as well. So I repainted the whole thing. It's held up quite well for this season of both SUP and windsurfing, and I'm pretty pleased how it came out. Anyway thought you might enjoy seeing an entirely different looking WindSUP: http://1drv.ms/1WHKPLE

James Douglass said...

Brandon- Wow, man! That's a gorgeous paint job. Looks like you have an awesome sailing spot there, too.