Ws323 cribby

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Issue 323 - MARCH 2013

SKIN TIGHT


Guy Cribb intuition

80 MARCH 2013


Technique

Skin Tight  Words GUY CRIBB Photos Guy Cribb INtuition guests including opening shot by Levi Tatham

TUNING

In the grand scheme of things, the importance of batten tension is not comparable with correct downhaul or harness line tuning, but is, perhaps for this very reason, the most overlooked tuning aspect I’ve seen. Most windsurfers unroll their sail and rig up, assuming the manufacturer has correctly pre-set the batten tension. This is not the case. More experienced windsurfers will apply tension to smooth out the wrinkles, experts will fine tune them and World cup racers will spend ages tweaking their battens with obsessive disorder. Whoever you are, if your sail had a smoother shape, with skin tight carbon batten tension, you’d be windsurfing slightly better. So after reading this feature, I hope you’ll understand why and how to perfect your batten tension and make the most of your windsurfing gear, time on the water and wind range of your sail with a few easy to remember pointers.

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Guy Cribb intuition Why? Spot the Difference.

Correct Batten Tension

No Batten Tension

More curve improving early planing Increased tension improving stability and therefore control Smoother foil improving speed by reducing drag

Flat sail ruining early planing Loose cloth is able to expand in the guests- yeah, hit a gust and this sail is going to get bigger - disaster! Drag - would you get on a plane with corrugated wings?

When? Adjusting the battens is the final tweak you make before going windsurfing, once everything else is totally rigged. Only if you are using a camber induced race sail should you increase the batten tension before rigging up. This feature is applicable for all sails- camber induced and rotational/ no-cams.

How?

1. Rig Up Firstly completely rig up, applying correct downhaul tension and outhaul. Most sails are designed to be rigged up on starboard tack/ right side up (where your front hand is your right hand.) This is partly because the battens are attached to one side of the sail, usually the right side as part of the manufacturing process sails are typically stitched together first and then have the batten pockets attached later. So ensure your sail is now positioned with the battens facing the sky, for 90% of you this will be right side up. All the battens need to be rotated to the correct side of the mast- the ground side of the mast, not sky side. Batten length…

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2. Position

3. Adjustment

Hold the back end of the batten and look down the length of it so you can really see the wrinkles. They cross the batten at 90 degrees. If you can’t see any, then move the rig around 90 degrees and see if they’re clearer - perhaps the sail is reflecting more colour off the mast sleeve now, making the wrinkles easier to spot? Only when you can clearly see the wrinkles should you start applying tension.

There are two main adjustment systems for tensioning battens- most brands use an Allen key that you’ll find either in a pocket on the bottom of your sail or in the sail bag - if you don’t have one try to borrow someone else’s on the beach, generally they are compatible between brands. NeilPryde use a magical integrated batten adjustment system. Both systems use the same concept that if you lengthen the batten it increases tension into the sail. To lengthen the batten you’ll need to unscrew the adjuster/ turn it anticlockwise.

is increased by turning the screw anti-clockwise….

which applies more tension into the sail cloth.


Technique 4. How much tension?

Some brands use Allen keys or integrated systems such as this Pryde BatCam to tension the rod.

For 95% of windsurfers and sails the same rules apply- only professional level racers and expert wave or freestyle sailors should fine tune further than this. The bottom 33% of your sail needs maximum batten tension. The top 33% just enough and the middle section somewhere in between. So, on a typical sixbatten sail the bottom two battens need maximum, the top two minimum... Maximum batten tension is totally smoothing out all the wrinkles- increasing tension until the last wrinkle clearly disappears, and then another half a turn. Minimum batten tension is to only just remove all the wrinkles. If wrinkles are clearly showing there is not enough batten tension. If you want to get really into batten tuning, shorter people can use less tension in the middle battens than taller people and wave and freestylers should use a little less in the bottom battens when conditions are good. We’re talking half a turn here and there, I’m not going to bore you with it!

Using two forefingers…

lift open catch…

adjust batten length…

close catch to apply tension.

Troubleshooting and common questions Wrinkles aren’t disappearing? Try turning the screw the other way- there are rare manufacturing moments where they used different systems. If still no luck applying tension it is likely the batten is broken - check for a sharp kink in it rather than a smooth bend, or the batten may have torn through its pocket at the mast end of the sail - quite common on the bottom two battens of your sail, especially if it’s been well-used or had years of too little downhaul tension (increasing the friction/ erosion of the batten pocket.) It will be difficult to visually see if this is the problem unless you totally de-rig, removing the sail from the mast.

Batten has an S-bend This is no problem as soon as there’s wind in the sail it should become C shaped.

Battens Don’t Rotate Correct downhaul tension allow battens to rotate smoothly on rotational sails. Increased batten tension does not make them harder to rotate. Camber induced sails do become harder to rotate with increased batten tension- but that’s partly why we use them for that extra rock solid stability. If your battens don’t rotate try more downhaul, if they still don’t rotate, try more outhaul. Failing that give them a good kick! Also in light winds battens/ sails are harder to rotate - try an aggressive pump, or more wind.  Higher quality freeride and race sails feature carbon battens. These are actually carbon cylindrical rods that have normal, flat fibreglass batten glued into the front of them, the carbon rod usually being approximately the back 66% of the overall batten.

Where these two composites join there is always a small wrinkle, about 33% back from the mast, that you won’t be able to eradicate, so don’t try! It’s easy to feel with your fingers if you have these kind of battens in your sail by running them along the length of the batten. Do I need to release the batten tension after use? No, leave them as they were- ready for the next time you go sailing. Do I ever need to readjust them again? If this is the first time you’ve applied batten tension, you should double check the tension half way through your session once everything has had a chance to stretch into shape and settle down, you may need to then apply more.

adjust batten length…

Also, approximately every 5 times you use your sail you should readjust the batten tension, it may only be a half turn of the screw, but keep at it.

Summary If we could we’d use carbon foils instead of windsurfing sails for some aspects of our sport, but they’re just not practical. Please use your batten tension correctly for the next best result and see if you notice the wind range of your sail increase, keeping you on the water for longer.

Guy Cribb INtuition

Britain’s Professional Windsurfing Coach and former multi-times UK champ. Guy Cribb INtuition runs exclusive windsurfing coaching courses for intermediates to experts in the world’s best locations, Hawaii, Australia, Brazil, Greece, Red Sea, Mauritius and more. Please check out guycribb.com for more info or see photos of the courses at Facebook/Guy Cribb Windsurfing INtuition. Copyright Guy Cribb 2013.

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