Frederik wrote:
Good luck with the conversion Hans-Erik.
And Arne. Could you say a bit more about the pros & cons between your an Victor’s sail design?
in a different thread maybe?
First of all, I didn’t know about Victor’s sailplan when I started on mine. My first take on it was very close to Victor’s version, with 70° yard , battens at 5.95m and SA= 63.5sqm.
However, I worried about weather helm. When a boat reaches 10 tons and has an un-balanced rudder, you’d better hit perfect balance, or you will struggle forever with the tiller (..or end up fitting hydraulic wheel steering...). Choosing a sloop JR instead of yawl, ketch or schooner makes it even more interesting.
That first sailplan wouldn’t let me shift the sail any further forward. Then, since I had just drawn a sloop JR for a fellow in NZ, I decided to try that one. This sail has been modified to a yard angle of just 65° and that allows one to increase its balance to as much as 21-22% versus only 16-17% with a 70° yard.
The rig shown below sits in its maximum forward position. Its CE is forward of the Bermuda rig’s CE, and about 50cm forward of the JR that Victor made. Still, this sail can be shifted 30-50cm aft in case of lee helm (unlikely). In other words, I feel that my second rig gives better freedom to fine-adjust the balance to produce a light helm.
This high-balance sail also brings the CE closer to the mast, so the increase in weather helm when reaching and running will be lower than with a low-balance sail of the same chord.
Combine the high balance with a 10° rise of the boom, and the boom will be less likely to dig into the sea.
Arne
PS: The centre of a real mast, at full thickness, will have to move 10-15cm aft of the thin mast line I have drawn, and so will the sail, of course. Its CE will nevertheless end up well forward of that of the Bermudan rig.
PPS: Does one live in or on NZ?