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Old 16th September 2010, 09:02 PM   #2
Dream Team - School Guru
Join Date: Aug 2006
Posts: 2,177

Hi Aleks,
My guess would be that you are not downhauling the 8.0 NP (which model? V8/V6/ other) enough.
This is a common issue for new "riggers" as they are afraid they will break the mast by bending it too much.
Do you have a downhauling tool (something with a crank handle that winds the downhaul line below the end of the extension and "winches" the sail down to bend the mast?
Also, do you have the correct NP mast for this sail?
You need to have the correct bend characteristics in your mast so when you downhaul to the reccommended specification with the recommended amount of extension, the sail and it's cambers are
rotated around the mast the right amount.
When you get the mast bent correctly, the cams should rotate fairly easily.
Also, if you have something other than the recommended NP mast, there could be a diameter difference that is causing the camber inducers to stick. Normally the mast will be larger in diameter than the correct NP mast, and the cambers have been designed to fit the recommended NP mast.
Are all of the cambers "sticking" or just some at the top (or more likely) the bottom?
Here's a quick way to tell how much you need to downhaul this (or any other) sail.
Lay the sail out flat (no mast inserted) on the wet sand near the waters edge, or on a smooth hard surface.
If on the wet sand, draw the luff curve that is sewn into the luff sleeve on your sail in the wet sand with a stick or a finger. Use a stick of chalk if you are on a hard surface like a parking lot.
Move the sail away from the curve you have drawn in the wet sand.
Insert the mast and adjust the mast base extension to the recommended length before inserting it into the bottom of the mast.
Thread your downhaul correctly through the pulleys on the sail and mast base.
Attach your downhaul tool and downhaul the sail with your "rig winch" to what you think it should be.
Move the sail back to the curve you drew in the sand or with the chalk.
See if the curve of the sail with the mast in it matches the curve you drew. If not, add more downhaul (usually the case) until the curve of the front of the mast matches the curve you drew in the sand or with chalk.
Your sail should now rotate as well as it is going to.
If you have minor mast compatability or diameter issues, there are things you can do to "rig around" some issues.
Other issues (like totally wrong mast bend characteristics) or much larger diameter mast, you cannot fix or rig around.
Also, I hope you realize that the camber inducers push pretty hard on the mast when correctly tensioned.
Have you tensioned the camber battens (actually all the battens)?
Also, most camber induced sails do "stick" a little and require a hard pump by the sailor to get them all
to rotate. They will never rotate "effortlessly" like a no cam sail.
You also need a bit of outhaul (at least neutral) to stabilize the clew so the sail can "pop" inside out.
The tension on the cambers is what puts the good shape in the sail and holds it there.
If there is no tension to hold the shape, or too much tension due to rigging issues or mast incompatability
the camber (s) may not rotate easily, and certainly not without a hearty pump on the rig to pop the cambers over with tension on them. Even roller cambers often need a little "pop" to get them around the mast and into the correct position each time you tack.
If you have enough wind speed, when the sail fills and starts to pull on the new tack, the cambers will often pop by themselves, but on a sail as big as an 8.0 I would expect you are out in fairly marginal conditions and there may simply not be enough pressure in the sail to overcome the normal amount of
camber tension.
Hope this helps,

Last edited by Roger; 16th September 2010 at 09:04 PM.
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