Peter Kafer wrote: > Ken, I've missed some of the posts on this subject, but am interested > in your comments about the Sailomat windvane. I have a Sailomat on my > Pearson 323. I have tried using it several times. A couple of times > it worked like a charm. Other times, I set it and within a few > seconds the vane steered the boat away from the intended course, > downwind I think. At any rate, it took off on its own. Once, I had > been following a course for a couple of hours and decided to tack, > using the vane to steer. Once I was on a new heading, the windvane > abruptly changed course. Whenever this happens, I think it turns > downwind, but I'll have to make more observations to verify this. > > Peter > Now or Never! > P323 I think you may already know a good deal of what I will say, but not knowing what you do or don't know, I will put more down.
There are a few things I do before I engage my vane. First, I make sure the sails are well balanced, so that there is little pressure on the tiller. With my boat being a former race boat she is easy to steer, you can balance her so she will steer with your little finger in nearly any conditions other than a gale. There will be some weather helm of course, but the pull will be light. The less the vane has to work against the faster its response will be in light conditions. In anything above moderate conditions, it could pull a barn door down it develops so much power, in fact I have the turning blocks on the stern rail mounted with break-away straps to save the stern rail in extreme conditions...it really could fold it in in a blow if it got to pulling, like if the sails got back winded or something. It will sure pull you straight across the cockpit if you don't dis-engage the tiller and give it a sudden yank! So it is PLENTY powerful, but all the forces must be finely balanced initially for it to work correctly. If it is not already set, before I engage the vane I adjust its internal linkage for the amount of feedback I think it will need and the amount of force it will need to make. This is easy again, since the main adjustment is a simple movable pin linkage near the top of the vane. In general upwind requires less lever arm on that linkage than downwind. Also I use tiller pulling lines that cross under the tiller at about chest height across the stern rail, and in the middle of where those lines cross the cockpit I have a section of SS chain where the tiller pulling line coming from the other side meets its partner at the end of the chain and connects via a spring-gate link, so that when that first tiller pulling line with the SS chain is pulled taught across the cockpit and then the its opposite partner is clipped onto one of the chain links, the two tiller pulling lines from the vane meet as one continuous line and cross the cockpit under the tiller and don't sag. This means there is less possibility of 'jerkiness' and lost effectiveness from wasted motion due to sloppy loose tiller pulling lines if the vane pulls from one direction and then rapidly reverses or relaxes in the other direction, or if yawing of the boat from downwind sailing and big seas causes the rudder to move the tiller it cannot jerk back and forth due to taught lines holding it. With this SS chain section in the mid point, the pin from the tiller can be placed at various points in the chain links giving it more or or less steering 'bias' as needed, just as you would hold the tiller offset when steering without the vane. Another adjustment that should be set when first setting up the vane is the fore and aft 'rake' of the entire unit and so the wind paddle, which makes a decided difference in how the thing behaves. I have found what I consider optimum for that and so never mess with it now unless it comes out of adjustment from maintenance or cleaning, but the position is marked. I think newer models have this setting more firmly locked down than mine. Having seen several types and different installations in operation over the decades I have observed that one of the biggest problems with proper operation of wind vanes seems to be friction. The Sail-O-Mat and many others go to great lengths to eliminate friction within the mechanism by using Delrin ball bearings and such design elements as that, then some goof-ball installs it with some great bunch of rusty, creaky old blocks and a convulted routing for the pulling lines that results in large amounts of friction and greatly impacts the performance of the system. On mine I used only two BIG ball bearing blocks per side for a minimum of friction. There are plenty of examples of successful wheel installations also, but I don't know details. However the Sail-O-Mat folks have always been very helpful whenever I have contacted them for any advice, and the guy who invented it seems to be a perfectionist who will go to great lengths to insure customer satisfaction. Back to how to use it, after getting the wind paddle rotated so that it stands up straight when I am close to the course I want I place the pin on the bottom of the tiller into a link of the SS chain connected to the pulling lines from the vane, and let the vane steer, making what slight adjustments are needed to move it to the final correct course, twisting the wind paddle relative to the wind until it stays straight up when I am on course. At this point I may decide to trim the sails a bit to give the boat more or less weather helm or to get the sails to draw better on that course and that may then cause me to tweak the vane a bit, moving the tiller in the chain a link or two, or twisting the wind paddle a tiny bit. There are a few more adjustments that can be made such as adding weight to the bottom of the wind paddle for light winds and rolly seas (I never have had to do that) or using a larger wind paddle for greater sensitivity in very light air, again something I have never needed at all. One thing is when I bought mine I got the next length longer for the steering oar, since I sometimes like to 'push it' going upwind and didn't like the idea of the steering oar loosing effectiveness when the rail is down. This means a bit of extra drag but it is worth it since my steering oar has never 'broken out'. As far as the boat changing course after the vane is engaged, the things that would be most likely to cause this are un-balanced sail trim, something changing the wind paddles air flow after it is set so that it no longer wants to be straight up while the boat is on the required course, such as disturbed air flow from something nearby maybe, (I had a friend that had a huge sun cover that messed with his vanes attempts to steer until he moved the vane, I would've got rid of the sun cover and its windage but that's just me), or just maybe the wind paddle is 180 deg in the wrong direction as that can sometimes make symptoms similar to what you describe also. This last is easy to fix, just rotate the wind paddle 180 deg! Don't forget that is is important to monitor the position of the wind paddle to see how it is standing right after a significant course change or after first engaging the vane, and to rotate it as needed and cause it to stand straight up when the boat reaches the correct course. The best way is to just get it close and then tweak it a couple of times, with practice this becomes just a twist to get on the ball-park course than another small twist to nail it perfectly. On my vane I used a center punch to make two marks on the body of the vertical tube that supports the wind paddle to show the correct position either side of the wind for taking, so all I need do is lift the tiller, tack, pick up speed and get my course good, and rotate the wind paddle to the other mark lock it down and I am off, or I can many times tack just by first rotating the wind paddle to the other mark and pulling the genoa over as the bow comes across. But that is not optimum as it is best to fall off a bit after tacking then ease back up, which can be done by moving the wind paddle past the tacking mark at first then after speed picks up sheeting the rest of the way in and tweaking the vane to the mark. Hope some of this is useful. -Ken _______________________________________________ Liveaboard mailing list [email protected] To adjust your membership settings over the web http://www.liveaboardnow.org/mailman/listinfo/liveaboard To subscribe send an email to [email protected] To unsubscribe send an email to [email protected] The archives are at http://www.liveaboardnow.org/pipermail/liveaboard/ To search the archives http://www.mail-archive.com/[email protected] The Mailman Users Guide can be found here http://www.gnu.org/software/mailman/mailman-member/index.html
