Someone asked me the other day if Arwen was a good self steerer? I felt somewhat stupid because as a newbie sailor I had no idea what the person was taking about! Anyway a quick query on John’s yahoo forum got the following responses from other navigator owners and Welsford builders. As always the forum came to my rescue again – thanks guys!
Apparently I should be able to achieve hands off steering to windward. It is all a matter of balance. Basically I have to balance the centre of effort of all the sails against the centre of lateral resistance of the hull. I’m told that isn’t as complicated as it sounds! Well according to Rob it isn’t but then he isn’t me.......I’m thicker than I sound or look!
Rob continues........
”With the centreboard and rudder fully down I should trim the sails at first jib then main and if applicable mizzen. They should be trimmed hard in with just a little of the luff lifting. I use the tiller to bring her up on the wind until all the sails are drawing in this manner. Then I let go of the tiller and see what happens! If the boat gently pulls up to windward and starts to luff, ease the mizzen a bit and maybe ease a little of the main (start with the mizzen) and see if that allows her to steer a straight course. If the bow bears off the wind tighten the mizzen to bring her head up and or main”.
I feel the need to get out my notebook and make some more annotated diagrams that I can refer to when out on the water!
“You can also shift the centre of lateral resistance by adjusting the centre board. In the event the boat is griping up to windward you can bring the board up a little this will move the plate area aft and move the centre of lat. resistance aft allowing the bow to fall off”.
Someone suggested that I may find I have excessive weather-helm (you need to pull on the tiller up toward the windward side of the boat all the time (note - should be a two finger job to steer). If this is the case I need to shift the centre of effort of the sails forward to blow the bow off a bit. This is not a massive adjustment to the rig. First I have to make sure that I have pushed the bottom of the mast as far forward as possible in the mast step on the floor. I should use a main halyard to make sure the mast is vertical by measuring to the top of the chain plate on each side. On a calm day whilst I am still on the hard, I should use a spirit-level to make sure the boat is level then hoist a plumb line to the main halyard and see where it lies with relation to the mast. At deck level it should be about 160-180mm aft for the yawl. Finally I should make sure that all these measurements stay constant whilst I tighten up the rigging to ensure that I have a taut jib luff. This is the preliminary set up. I then go sailing and put the boat hard on the wind - trim the sails and I should have a light weather helm (two finger).
If I still have a bit too much weather-helm I’m to tighten the fore stay and ease the shrouds (do it one turn at a time) and I should find that the weather-helm eases as the rig is moved forward. It is a good idea to make sure that the mizzen is well eased at first so that its effect does not confuse me to start with. [Right now there is a very distinct possibility that I am terribly confused but it isn’t to do with the quality of the advice given, merely my inability to internalise and understand it!]. If I have it about right I can use the mizzen and centreboard position to fine tune.
“Make sure that you allow the boat to sail herself. She will naturally change heading due to wave action but you should find that she will hunt either side of the optimum course. Remember a rudder at large angle is a large brake so she needs to be sailed at minimum rudder angles, try not to be constantly adjusting the tiller when you are helming as you are just slowing her down”.
“A bungee shock cord or light line can be strung across the cockpit to keep the tiller on the centre line or there abouts”.
“The tuning exercise on the water requires time and patience and about 10-15 knots of wind, so don’t try to do it on a family outing day. Set a morning or afternoon aside and bring a crew along who understands what you are trying to do”.
Good tip – sadly I have no crew who remotely understands anything I do...mainly because I have no idea what I’m doing most of the time!
Owen offered this contribution......
“I have achieved this on occasion in my Navigator. The trouble is that, in a light boat, the moment you move from the helm the balance of the boat changes and it no longer holds the course. To do it, hold the tiller very lightly or allow it to move between your fingers and thumb when sailing to windward and adjust the sails, primarily the main and mizzen but one at a time, until the boat is steering itself. Needless to say the wind and sea conditions need to be very constant. I don't think I have ever tried it in more than a very light chop. But it's fun to achieve”.
Just as I was getting my head around these excellent tips – in came John himself to the debate!
“I have found on the two Navigators that I've sailed more than others, that I could sail just slightly free, with the mizzen sheeted slightly hard to generate more weather helm and a length of surgical tubing on the tiller and get them to self steer on the wind. Surgical tubing can be purchased from medical supply houses, and some co operative chemists or vet surgeries will get it in for you. It has the advantage over shock cord that it has a very low initial stretch load and a much more progressive increase with extension”.
“In any normally shaped monohull you can make them point a little higher by moving your weight forwards, and bear away by moving aft. The two yawl rigged Navigators that I've done significant mileage in both did this, and even my 18ft gaff sloop weighing in at over a ton with crew and stores does it. There is a very good book on self steering in small sailing boats,
http://www.amazon.com/Self-Steering-Sailing-Craft-John-Letcher/dp/0877420424
This book covers mostly sheet to tiller and sail trim methods rather than a wind-vane, and in a reasonably well balanced boat these methods can be very effective”.
Ah – some more reading to do!
Pete V had this to say.........
“Some points of sail are easy, and some hard. Using a simple system, like a tied tiller, if you are trying to point high, and a wave bounces you too close to head-to-wind, the jib will lose the power to make the boat fall off. Also if you are heading well downwind, it's hard to get the boat to fall off again to a deep angle.
But in the middle, especially from a close reach to a beam reach, it's pretty easy to make a good boat steer herself in moderate conditions. Fun, too”
Richard Schmidt of Bootstrap fame then offered up two lovely video clips of him proving that it can be done in a navigator – well done Richard and thanks for the inspiration.
https://picasaweb.google.com/hangstrap/BootstrapStability#5282886383171484306
https://picasaweb.google.com/hangstrap/BootstrapStability#5282886383171484306
Now let me see if I can draw some diagrams to annotate all this lot so that when I’m out in Arwen....I can put some of it in to practice!
Thanks everyone for their contributions – the reason I get better at sailing is because of the advice offered by experienced sailors like yourselves. Much appreciated.
Steve
Apparently I should be able to achieve hands off steering to windward. It is all a matter of balance. Basically I have to balance the centre of effort of all the sails against the centre of lateral resistance of the hull. I’m told that isn’t as complicated as it sounds! Well according to Rob it isn’t but then he isn’t me.......I’m thicker than I sound or look!
Rob continues........
”With the centreboard and rudder fully down I should trim the sails at first jib then main and if applicable mizzen. They should be trimmed hard in with just a little of the luff lifting. I use the tiller to bring her up on the wind until all the sails are drawing in this manner. Then I let go of the tiller and see what happens! If the boat gently pulls up to windward and starts to luff, ease the mizzen a bit and maybe ease a little of the main (start with the mizzen) and see if that allows her to steer a straight course. If the bow bears off the wind tighten the mizzen to bring her head up and or main”.
I feel the need to get out my notebook and make some more annotated diagrams that I can refer to when out on the water!
“You can also shift the centre of lateral resistance by adjusting the centre board. In the event the boat is griping up to windward you can bring the board up a little this will move the plate area aft and move the centre of lat. resistance aft allowing the bow to fall off”.
The master himself - Dave Perillo and 'Jaunty'
I bet he could self steer that boat!
Someone suggested that I may find I have excessive weather-helm (you need to pull on the tiller up toward the windward side of the boat all the time (note - should be a two finger job to steer). If this is the case I need to shift the centre of effort of the sails forward to blow the bow off a bit. This is not a massive adjustment to the rig. First I have to make sure that I have pushed the bottom of the mast as far forward as possible in the mast step on the floor. I should use a main halyard to make sure the mast is vertical by measuring to the top of the chain plate on each side. On a calm day whilst I am still on the hard, I should use a spirit-level to make sure the boat is level then hoist a plumb line to the main halyard and see where it lies with relation to the mast. At deck level it should be about 160-180mm aft for the yawl. Finally I should make sure that all these measurements stay constant whilst I tighten up the rigging to ensure that I have a taut jib luff. This is the preliminary set up. I then go sailing and put the boat hard on the wind - trim the sails and I should have a light weather helm (two finger).
If I still have a bit too much weather-helm I’m to tighten the fore stay and ease the shrouds (do it one turn at a time) and I should find that the weather-helm eases as the rig is moved forward. It is a good idea to make sure that the mizzen is well eased at first so that its effect does not confuse me to start with. [Right now there is a very distinct possibility that I am terribly confused but it isn’t to do with the quality of the advice given, merely my inability to internalise and understand it!]. If I have it about right I can use the mizzen and centreboard position to fine tune.
“Make sure that you allow the boat to sail herself. She will naturally change heading due to wave action but you should find that she will hunt either side of the optimum course. Remember a rudder at large angle is a large brake so she needs to be sailed at minimum rudder angles, try not to be constantly adjusting the tiller when you are helming as you are just slowing her down”.
“A bungee shock cord or light line can be strung across the cockpit to keep the tiller on the centre line or there abouts”.
“The tuning exercise on the water requires time and patience and about 10-15 knots of wind, so don’t try to do it on a family outing day. Set a morning or afternoon aside and bring a crew along who understands what you are trying to do”.
Good tip – sadly I have no crew who remotely understands anything I do...mainly because I have no idea what I’m doing most of the time!
and you can bet your life that Barrett knows how to self steer 'Yuko'
Owen offered this contribution......
“I have achieved this on occasion in my Navigator. The trouble is that, in a light boat, the moment you move from the helm the balance of the boat changes and it no longer holds the course. To do it, hold the tiller very lightly or allow it to move between your fingers and thumb when sailing to windward and adjust the sails, primarily the main and mizzen but one at a time, until the boat is steering itself. Needless to say the wind and sea conditions need to be very constant. I don't think I have ever tried it in more than a very light chop. But it's fun to achieve”.
Just as I was getting my head around these excellent tips – in came John himself to the debate!
“I have found on the two Navigators that I've sailed more than others, that I could sail just slightly free, with the mizzen sheeted slightly hard to generate more weather helm and a length of surgical tubing on the tiller and get them to self steer on the wind. Surgical tubing can be purchased from medical supply houses, and some co operative chemists or vet surgeries will get it in for you. It has the advantage over shock cord that it has a very low initial stretch load and a much more progressive increase with extension”.
“In any normally shaped monohull you can make them point a little higher by moving your weight forwards, and bear away by moving aft. The two yawl rigged Navigators that I've done significant mileage in both did this, and even my 18ft gaff sloop weighing in at over a ton with crew and stores does it. There is a very good book on self steering in small sailing boats,
http://www.amazon.com/Self-Steering-Sailing-Craft-John-Letcher/dp/0877420424
This book covers mostly sheet to tiller and sail trim methods rather than a wind-vane, and in a reasonably well balanced boat these methods can be very effective”.
Ah – some more reading to do!
..and sorry I don't know who this is and couldn't find an acknowledgement on the net.....but you
just know....they are bound to be able to sail a navigator by self steering......
Pete V had this to say.........
“Some points of sail are easy, and some hard. Using a simple system, like a tied tiller, if you are trying to point high, and a wave bounces you too close to head-to-wind, the jib will lose the power to make the boat fall off. Also if you are heading well downwind, it's hard to get the boat to fall off again to a deep angle.
But in the middle, especially from a close reach to a beam reach, it's pretty easy to make a good boat steer herself in moderate conditions. Fun, too”
Richard Schmidt of Bootstrap fame then offered up two lovely video clips of him proving that it can be done in a navigator – well done Richard and thanks for the inspiration.
https://picasaweb.google.com/hangstrap/BootstrapStability#5282886383171484306
https://picasaweb.google.com/hangstrap/BootstrapStability#5282886383171484306
Now let me see if I can draw some diagrams to annotate all this lot so that when I’m out in Arwen....I can put some of it in to practice!
Thanks everyone for their contributions – the reason I get better at sailing is because of the advice offered by experienced sailors like yourselves. Much appreciated.
Steve
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