Hi there
At one point, it was a new concept for all of us!
I can only tell you what I did, and what I learned from my mistakes, so it´s not “advice”!
I modelled it on paper. Made a print to scale of the boat from the original brochure, and then overimposed the sail design from Ullman to the same scale. Example below.
On this “template”, I placed two bars representing the booms, also to scale. The “correct” angle of the boom forward WRT the horizontal I eyeballed by looking at every pic and clip of a Hoyt CK 30 and 35 under sail that I could find on the web, and asked around in this forum and others.
- Nausica rig layout v3.jpg (22.86 KiB) Viewed 3003 times
This exercise helped. As you can see on my pic, the original cut by Ullman was more suitable to a sailboard than a boat, as the clew was way too high, and the tack way too low, on both sails. Based on this view, I asked Ullman to change the overall design to the red outline in the pic.
Now, on a normal fixed boom rig, where the boom and the foot of the sail are parallel to the horizontal of the boat, and both of these are at 90 deg to the mast, the reef attachment points on the leach and luff of the sail also need to be aligned with each other and close to parallel to the horizontal.
Not so in in our rig! The wishbone boom is not parallel to the horizontal, but at an angle. The luff reef attachment point needs to be higher than the leech point, so that the effective foot of the sail when reefed remains more or less parallel to the horizontal. How much higher will depend on the angle you carry your boom forward.
In your sail design, you will see the sailmaker put the attachment points for the reefs as if the sail were to fit on a “normal” fixed boom with a boom vang and/or kicking strap, where the boom is parallel to the horizontal and at 90 deg to the mast. This is what they would normally do, but it does not fit our rig. If you were to reef your sail with an angled boom, you’ll find that when the leech reef attachment point is brought down towards the aft end of the angled boom (as it would be under tension by the reefing line), the luff attachment point will sit very low, way below the choker of the boom. IMO (only my opinion based on my sails, with single-line reefing, and with the angle I carry my boom!), with the sail reefed, the luff reef attachment point should sit between one and two feet the boom choker, but not much more than that. This setup gives me the best sail shape when reefed, and also gives me sufficient room on the forward section of the boom between the arms of the wishbone to flake all the sail that falls below the reef.
In short, my suggestion is that you model this on paper first, and estimate where the reef attachment points should go according to the angle of your boom. I did it in Powerpoint, so you don´t need any special graphic design SW.
Below is also a pic of Nausikaa with the main on the first reef, and the mizzen on the second reef. This just to show you how my sails hang when reefed.
Hope it helps.
Rafa
- Nausikaa reefed.jpeg (388.78 KiB) Viewed 3003 times