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Old 17th July 2010, 05:27 AM   #16
basher
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Join Date: Aug 2006
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Quote:
Originally Posted by kiwiben View Post
I would estimate that in my first 100 windsurfing sessions, about 95 of them I didn't have enough downhaul. It seems obvious now, but at the time I just didn't know.

What do you all think would be the top 5 mistakes for a person in their first 100 riggings, presuming they are sailing unsupervised like I did...

My guess for me would be:

1, Not enough downhaul
2. sail too small
3. board too big (after becoming good at waterstarts)
4. sail too big
5. ???

After the first 4 I get a bit vague. Would it be line placement? Mast track placement? outhaul wrong?
This is a cry for help to get me focussed on what next, now that I know how to prevent the first 4 from happening... please answer my desperate call...

I don't post on here much but as someone who used to work for a sailmaker, I'm a bit horrified by some of the answers to this thread.

The batten thing, for a start.
Battens are there to hold the leech away from the luff and to stabilise the panels of the sail. The top battens support the head (roach) of the sail. The stiffness of the battens helps with the stability of the sail.

But the batten tensioner on rotational sails is just there to take the wrinkles out of the sail panels and no more. Extra tension tries to overstretch the batten pocket and wrongly pre-tensions the batten with compressional load which only encourages the batten to bend which you don't usually want. So set your battens just lightly tensioned to minimise creases in the sail. The batten tensioner is not a tuning device.

Camber-induced sails are slightly different in that the batten tensioner can push the batten end onto the mast. So extra tension here can change the front shape of the sail by pushing in more fullness in the luff via a hingeing cam. Over-tightening these cam battens can in turn make the sail difficult to 'tack' or rotate.
Having said all that, most cams are now sewn into the sail or else pushed snuggly onto the forward end of a fixed length batten pocket so again, batten tension doesn't do much more than try to stretch this batten pocket, usually with no good outcome.
On the cam'd sails I use, I can increase the cam pressure on the mast by fitting a plastic 'spacer' between the cam and forward batten pocket end. This spacer is the tuning device, not the batten tensioner.


As far a downhaul goes, it is true that most people still learning don't go far enough with downhaul tension when rigging their sails.
However, I also see a whole generation of sailors on some beaches who are so frightened of not having enough downhaul on their sails that they downhaul them far too much. And then they wonder why the sail has no power in lighter winds.
If you want to get to the truth about downhaul it's simply that this tension bends the mast to release or twist the leech on the beach. When you sail however, your body weight hanging of the rig bends the mast further to one side and the leech tightens under this sailing load. Heavier sailors load their masts more, often using larger sails, and so they need more downhaul tension than lighter sailors.

The key to good rigging is feel. Learn to feel if your sail is not working properly. If rigged well it should feel light in the hands but still powerful in the wind lulls. The drive should be constant, with your harness lines staying on one place opposite a stable centre of pull.
So downhaul and outhaul ARE your sail tuning devices.


One other issue here: I see many sailors on boards way to small for them.
Unless you are riding big waves or sailing in strong winds there is no need for you to be on a sinking board. Make sure your board floats you when the wind drops, with plenty of buoyancy under the straps.
The key, even for a wave board, is to be honest about your body weight and make sure you have 'positive float' by sailing a board with a volume in litres that is at least equal to your body weight in kilos. Add 5 or 10litres volume to float the weight of the rig too.
Modern designs handle wind and water conditions well without sinking in the water. And just because you loved your 70 litre waveboad when you were 18, doesn't mean you can sail the same small size board when you are 35 (and usually a lot heavier). Float is your friend.

The worst thing we see all the time is big people on sinky boards not planing. They then fit over-size fins to their boards in the hope of planing or staying upwind. In fact a board that planes early does so through positive buoyancy, and it is you planing easily that will get you upwind, not an oversize fin on a sinky board that won't plane in the first place.

I'm lecturing now, so I'll shut up.
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