Twist Control

[Ranger Paul]

I have a Hunter 216. I want to be able to control the main sail twist easily when close hauled with the main sheet trimmed tightly, that is, with a lot of tension on the main sheet. Specifically I want to hold up the boom with something adjustable. Obviously if I used something adjustable and wanted to increase twist, I would have to ease the main sheet, make the adjustment, then trim the sheet.There seems to be three choices, the topping lift, a boom kicker or a rigid vang. Topping lift - Using the topping lift for this purpose doesn't seem like a good idea to me for a couple reasons, 1) it could be nasty if it broke under the load and 2) I have a fractional rig and I'm not fond of the load I would put on the upper section of the mast above the top shroud/forestay tangs. I admit to being green enough that I don't know if topping lifts are used for this purpose. Further, the topping lift has to be to the weather side and it would be difficult to switch from one side to another.Boom kicker - I suspect these do not have enough "kick" to overcome the main sheet tension when close hauled.Rigid vang - Been looking at the Garhauer (as it is the only one I can afford!) Will this have enough "up" force with the in-build springs to induce the twist I want? This could be a nice choice for me as the 8:1 vang that came with my boat is inadequate.Any advice would be greatly appreciated.Happy Sailing

 

[John]

Controlling twist while pointing?

Maybe I dont understand your question.? The topping lift and boom kicker only hold the boom up, but dont do much when under sail. I control twist with a boom vang - especially DOWN wind. It sounds to me like you're needing a traveller, so you can travel the boom over when you're pointing high.

 

[Ranger Paul18580]

Controlling twist clarification

Here's what I want to do: I want to increase the twist when my non-rigid boom vang is totally loose, I am close hauled, and the main sheet tension is keeping the leech too tight for the twist I want. For example, this weekend we were sailing in light 3-5 mph winds. When close hauled, the top batten was not parallel to the boom and the top leech telltale was stalled to leeward. I could cure the stall by 1) readjusting the tension on the top batten (impractical while underway), 2) easing the main sheet or 3) increasing twist. To maintain my pointing angle, it seems the best thing to do is increase the twist slightly.How do I do this? BTW: I do not have an adjustable backstay. I do have an open foot main so draft adjustment for the lower part of the main is easy. I judge the draft on my upper batten position was about right for the wind conditions.

 

[Wanderer138]

Sailing in very light air - for Alan

Alan:I hope I didn't misunderstand your post, but you seem to be confusing "twist" with "draft".Twist is the change of angle of attack (the angle of the chord of the sail to the wind) as you go up the sail, while draft (or "camber" as you put it) would be the displacement of the sail from the chord length, i.e. its "depth".That being said, I agree with you 100% regarding the need to reduce draft to keep the airflow attached in light air.PeterH23 "Raven"