Tuning Guide

Rigging

1. Avoid abrasive surfaces.
2. You can't just push the mast into the sleeve, you need to work it on bit by bit. You need to 'compress' the sock. This may be something you don't want to do with your new acquisition, but does far less damage than trying to force it up.
3. For cambered sails, attempt to keep the cams on the mast, but if they come off, just leave them of until you get the boom on.
4. Put a moderate amount of down haul then attach the boom.
5. For large cambered sails you need to fully tension the outhaul and have the downhaul very slack if you need to pop the cambers on.
6. Tension downhaul and outhaul to your preferred settings.
7. Read the tips below.
8. The measurements on the sails are to help choose equipment and not for final tuning.
9. Have fun and most importantly - don't be afraid to experiment to find what is right for you.
10. Remember: as your sailing improves, or you change other pieces of equipment, your sail settings should also change.
    

Downhaul
The top and leech of the sail are designed to be loose and fall away to leeward, twisting under load. This is achieved with high downhaul tension. It is very common to see sails rigged with too little downhaul tension. You won't pull the sail apart or break the mast, so don't be shy - give it a big tug! Once the correct downhaul setting is found, it does not need to be changed much although slightly (<2cm) less for very light wind may help you get on the plane. The main adjustment is done with the:

Outhaul
Tension the outhaul more for overpowered conditions. Experiment with the outhaul setting in different conditions - it is easier to adjust and unlike the downhaul there is no "correct" setting. Too much tension will kill the acceleration and downwind performance, not enough will cause instability in high winds and lack of pointing ability.

Want more power - less tension / Want more control - more tension.

The correct balance of outhaul tension and downhaul tension is essential for optimum tuning. With time you will develop a feel for your own settings.
Experimenting with different settings will teach you the different feelings and with time you will notice the changes in performance. Once the downhaul is correctly tensioned, minute adjustments in outhaul tension will change the sail's performance.
If the sail feels sluggish and heavy, you probably need more downhaul. If the sail feels light, yet a bit powerless, you probably have too much downhaul or too much outhaul. It's often a fine line between right and wrong setting, so it pays to experiment a bit until you feel comfortable with the sail.

De-rigging
Ease the downhaul slightly. Remove the boom. Undo the downhaul, slide the mast from the sail. Roll the sail from the top, preferably clean and dry.

MAINTENANCE

Store in sailbag and prevent crushing. Wash the sail with fresh water whenever possible, and especially before long term storage. Make sure the sail is dried after washing with fresh water to avoid mould forming. Try to keep the sail free of sand and dirt. Rolling the sail while sandy will scratch the monofilm and eventually make it opaque.
Dirty film on the clear panels may be cleaned with a soft brush or cloth and dish washing liquid.
Repair any small tears with clear mylar tape or a sticker. Make sure the area is clean and dry. Larger tears should be repaired by a sailmaker.
If leaving the sail rigged for long periods, especially in hot weather or direct sun, release downhaul tension slightly to reduce load on the rig. Store in shade if possible. (Reducing the area exposed to the sun by aligning sail to sun helps. )

FREQUENTLY ASKED QUESTIONS

I have a Formula 10.5. It is a great sail and gets my board planning in just about no wind, but when I am rigging it, the cams pop off. Can you give any tips as to stop this from happening? Paul.

...I've solved the problem myself, I leave the tension on the battens and when I slide the mast up and keep pressure on the downhaul preventing the sail sliding back up the mast, this seems to help, no more problems: just good sailing from a good sail, Paul.

(Ed - Thanks Paul, you are right on the money. Are gunning for my job?)

Which masts are the best choice for the KA Formula sails?

Our primary test mast for all sails currently is Powerex, as they have the most even and consistent bend curves.

If you have any information with regards to batten tension I would be interested in it. I know that the batten tension is normally set by the factory however I would like to know under what circumstance it should be used and how.

The batten tension is not fully set in the factory. You simply need to tighten them just enough to remove all wrinkles along the batten with the full downhaul set. You will find that the top battens need less than the lower battens. Over tensioning the battens, particularly at the top will cause leach flutter.

I am not sure whether or not the batten tuning screws should be loosened for rig/de-rig.

We do not think it is necessary for no cam sails.

I've got a question about how to rig my Kaos 5.7 which I purchased recently. I would like to know how much I should downhaul my sail. On your website you only mention: 'a lot'?

A lot!..... Seriously, this is a very personal question. The leach should almost always be loose between battens 1-2, and most probably between 2-3. at 1-2 the looseness will need to be about half way for stronger winds. 2-3 maybe a 1/4.

Even with lots of downhaul tension batten 4 and 5 are pushing against the mast which makes rotation of the sail more difficult (but still okay). Is this normal? I use the recommended mast.

At high downhaul the rotation is certainly not as easy, and as you say the battens push against the mast IF you have the outhaul loose. For properly powered up sailing the outhaul will be tight enough that the battens will be far enough back that they do not touch the mast.

This is how a Kult should be rigged for anything but the lightest winds. Note the transition from highly tensioned to loose at 1/3 back in the top section of the sail.

Why do I get creases running from the batten above the boom to the batten above when the sail is under load on my 2003 sail?

This question was particulaly aimed at the Kaos 5.7 but is relevent to all sizes and ranges. We reviewed the sails and find they are as designed.

In order of importance our design requirements are:

1. The sail must be light feeling
2. The sail must balanced
3. The sail must be well behaved in strong winds
4. The sail must be lively in light winds
5. The sail must withstand usage it is intended for
6. The sail should be physically light
7. The sail layout should look pleasing
8. The sail should rig cleanly when not under load
9. The sail should rig easily
10. The sail should not crease to much under load
11. The sail should still perform when not tuned optimally
12. The sail should tune easily to its optimum setting

Points 1, 2, 3 and 4 are not only the important ones on the list, but also are in direct conflict with point 10.
This is because we do the following to the designs to optimise these factors, that both cause creasing under load:

• We add shaping in the forward central area of the sail when other designers actually suck shaping out here.
• We keep the luff curve straighter than the mast bend in the central area.
  These design features are a large part of why our sails have the performance qualities that people love. We will never again compromise performance for looks, or what some may consider to be imperfect.
• We once did this when we introduced the over twisted head that many World Cup sailors bought from us to use in the even when they were sponsored by other brands. The every day sailors did not like the look of the head, so we bowed to the retailers wishes and tightened it up. The result was that we compromised the performance and missed being the global design leaders for this trend.

In relation to the question about the 5.7, it has a very different design brief to the smaller sizes, as always is with largest size in a range. It must cover a greater wind range, so the balance of the performance/aesthetics is tilted even more towards the performance end. To achieve this, the 5.7 has more shaping in the centre panels which is offset by less luff curve. This will invariably give rise to more creasing when under load.

The bottom line: I would like to ask your sailors is, if they ignore the creasing, did they like the sail.....

I hope this is helpful. For 2004 we will review options to try to address this.