Yea I would prefer end boom sheeting with a tiller but my boat was set-up with a wheel and mid boom sheeting. If I was going to keep her forever I'd probably convert it. Brandon Snider Charleston SC 5886
On Thu, Jun 11, 2009 at 11:20 AM, Sneddon, Keith - ES/IS < [email protected]> wrote: > > > This all comes down to the physics. To trim your main, you have to pull > against a force (the lateral force on the main) through a distance (the > angle the boom moves). The product of force times distance is work. When you > pull on the end of the boom, you are pulling the same angle to achieve > proper flow, but the point you are pulling on is moving a lot farther than > if you have mid-boom sheeting. To do the same amount of work, you don’t need > to pull as hard. To put some rough numbers to it, if you pull at the mid > span of the boom, you have to pull twice as hard for half the distance. To > get back to a reasonable pull force, you can add purchase (8:1 vs. 4:1 > pulley setup, for example) to trade back distance for force. Nothing is ever > free, however, and each layer of purchase adds drag, which hurts in both > directions (sheeting in and out). Big sheet tension hurts drag too, as the > frictional force is directly proportional to the sheet tension. > > For this, and a bunch of other reasons, end boom sheeting is mechanically > more efficient, but Sailboat Design, like life, is a series of compromises > and imperfect solutions. There are a lot of practical advantages to mid-boom > sheeting. > > > > Keith Sneddon > > #4760, “Are We There Yet?” > ------------------------------ > > *From:* [email protected] [mailto:[email protected]] *On Behalf Of > *Tim Millar > *Sent:* Thursday, June 11, 2009 10:49 AM > *To:* [email protected] > *Subject:* Re: [IC27A] Main sheet trim > > > > > > > Jeff, > > > > I have the same original setup on our 1986 and agree that it can be > difficult. Hope we can get an explanation and solution. > > > > Tim > > Sea Scout Ship 76 > > *Spirit*, #6254 > > > > > > On Jun 11, 2009, at 10:29 AM, jlenox225 wrote: > > > > > > I searched the forum and did not find any other posts regarding this issue. > Does anyone else have trouble trimming and easing their main. I have mid > boom sheeting to the original cabin top traveler. I find that the sheet > binds up when I try to ease it under load and I need to assist it by feeding > line from where the sheet enters the aft most block on the boom. When > sailing to weather it seems like there is a significant load on the sheet > when trimming which requires the use of the winch handle. I would even say > that with the sails down, to fully sheet the boom amidships it feels a bit > tight. It would seem that it binds somewhere in the turns from the winch to > the turningblocks on deck to the 3 blocks which redirect the sheet to the > traveler. I found that I had the same problem on my S2 27 which had a > similar set up. It appears by looking at other C27s that this is the > standard set up. I hope I explained this in a not too confusing manner. > Thanks, > Jeff > > > > ------------------------------ > This e-mail and any files transmitted with it may be proprietary and are > intended solely for the use of the individual or entity to whom they are > addressed. If you have received this e-mail in error please notify the > sender. > Please note that any views or opinions presented in this e-mail are solely > those of the author and do not necessarily represent those of ITT > Corporation. The recipient should check this e-mail and any attachments for > the presence of viruses. ITT accepts no liability for any damage caused by > any virus transmitted by this e-mail. > > > -- Richard "Brandon" Snider 843-616-3124
