As
@DrJudyB would attest to, the jib sheet is in a good place when it roughly intersects the sail 1/2 way up.
This scenario does, can and will change, but as a simple exercise, it’s a great place to start.
The boat in the picture may be an anomaly. The picture would have one (ok maybe I’m the only one) believe the car is too far forward. The trouble is, the foot of the sail has what appears to be a less than excessive shape, indicating that maybe the happy couple
Yes this is it. I have a 1996. I snipped a picture from the brochure that shows the jib sheets tracking to the top of the cabin. I installed Lewmar CST 30 two speed winches back by the helm. the cheek blocks are located where I circled in the picture on the vertical surface. That is why I had to cant them a little bit to center the line in the pulley portion of the block.
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@Meriachee tagged me, so I thought I’d drop in for a short post to this thread.
The angle of the photo is not square to the beam, so there’s foreshortening. In addition, the boat isn’t close hauled (look at the boom) so the clew is rising.
As Meriachee pointed out , a vertical angle intersecting 1/2 way up the luff is only a starting point. As a rule of thumb It produces precision results only for a very limited application. The analysis is specific useful when designing on paper, drawn in non curved, 2D projection onto a plane side view, for mid sized genoas.
This picture Is of a jib of less than 105%, a #3, a high aspect sail. High aspect sails need comparatively more leech tension to control leech twist, so I’d expect to see the vertical sheeting angle intersecting the luff a little higher than 1/2 way. ( When viewed In a 90 degree side view, when you draw it out on a paper.).
In summary,the specification of vertical sheeting angle is all about controlling leech tension and twist. Keep in mind that as you ease the sheet from close hauled to furtheroutboard, leech tension will decrease more than foot tension, so the sail will twist more (and ifthe clew is a low height, the clew will tend to hook inward, which is undesirable)
This is a complex topic, and I’ve simplified it. I would caution against using my comments as a basis for calculating the dimensions of the edges of your next headsail.
Judy B