Self-steering options

[Samsara]

New to this thread and new to yacht ownership, however, in for a penny …

My timber gaff-rigged cutter is 35ft and weighs approx 14 tonnes. She is of course tiller-steered and tends to be ‘heavy’ when not balanced enough to enable me to leave the helm.

The transom is rather encumbered with overhanging davits supporting the usual kayak, ladder, fender-board etc.

Can anyone assist please with a self-steering set-up - I’m very keen to learn to sail Samsara single-handed?



Paul

 

[jamie N]

Welcome to the forum.
I think that to be able to have any self steering, you're going to face a choice of either keeping the stuff hanging off of the stern and go with an electric tiller pilot, or to relocate all of that around the (very lovely) boat, and fit one of the tried and trusted wind vane designs at the stern, once it's clear.
You mention that the boat is unbalanced, you'll find that nothing will work well until you've got her balanced, which could mean only having 'some' of your available canvas flying at any one time.

 

[Samsara]

Welcome to the forum.
I think that to be able to have any self steering, you're going to face a choice of either keeping the stuff hanging off of the stern and go with an electric tiller pilot, or to relocate all of that around the (very lovely) boat, and fit one of the tried and trusted wind vane designs at the stern, once it's clear.
You mention that the boat is unbalanced, you'll find that nothing will work well until you've got her balanced, which could mean only having 'some' of your available canvas flying at any one time.

Thank you Jamie.

I agree with the choices and had always pondered some form of electric autopilot, however, considering the weight of 14 tonnes and the large paddle-style rudder, is there a unit of ‘heavy-duty’ capabilities?

The issue of weather-helm is almost rectified with the order of a larger jib. Side note: don’t think I’d ever get to raise the flying jib or topsail unless a crew of 3 others could be found who were equally as keen to risk life and limb …

 

[Praxinoscope]

I agree with jamie N, at present you couldn't fit self steering without removing the kit currently on the stern, but there are several units that should be suitable for you boat and that nothing will really work if the boat is unbalanced.
My biggest regret is that I let the self steering gear go with my last boat when I sold her, eleçtric tiller pilots are OK but wind vane self steering seems so much more pleasant.

 

[Wansworth]

If your into diy build a two part stowing dinghy for behind the mast and out of Bill Belchers book yacht wind vane steering build a servo wind vane.

 

[srm]

Nice looking boat.

My Monitor gear was bought second hand. It had completed an Atlantic circuit on a Colin Archer type ketch so would suit your boat provided that (as said above) the rig/hull can be balanced for the point of sailing so that the helm just needs slight movements. The swing and tiller movement of any servo pendulum gear is limited. If you go to the Monitor web site you can probably download the manual which explains the system well. My Monitor works well and has steered for a few thousand miles in all conditions from just keeping steerage way to big seas and F8. This is despite being on a narrow transom with a gantry for solar and radar. I had to trim the big wind vane so it will swing inside the gantry on a reach.

If going for electronics you will need a proper autopilot set up rather than a yacht tiller pilot which will not be up to the job. You will be able to find suitable equipment, probably aimed at the commercial work boat market rather than yachts given the size and weight of your boat. Purchase and installation will be expensive and you will also need to consider how you will generate enough power to keep it running.

Since first fitting a wind vane steering gear on my second yacht in the mid 70's I have not been without it, fitting one to each of my sailing boats. Even with a crew it makes sailing and watchkeeping a lot easier and on longer passages/night sailing steers a more consistent course than most people can hold after their first half hour on the helm. It will, however, follow any wind shift so needs watching.

 

[jwilson]

No off the shelf "tiller pilot" will handle this. A ram drive (as normally installed below decks) will do, but they are not designed to get wet so will need some ingenuity to fit above deck, and power consumption will be high if helm loads are high. Or give up the dinghy etc. on davits and fit a servo-paddle vane gear.

 

[LittleSister]

There is a potential compromise between conventional wind-vane steering and an electric autopilot.

As far as I can see from the photo it is the dinghy on the back on the boat is the main issue preventing installation of conventional wind-vane steering. The dinghy is in the position that the wind-vane itself would normally go, and any other location nearby would be out of clear wind.

However, a servo-paddle set up could be installed on the transom under the dinghy, and this could be controlled by an electric autopilot (in turn referenced to either magnetic headings or, by using the input from a wind direction instrument, the apparent wind. The electric autopilot would only angle the servo-blade, while the servo blade would be doing the hard work of actually turning the rudder. In this way the electric consumption would be a tiny fraction of that were the autopilot operating the rudder itself, and the electric autopilot could be a much lower powered, smaller and cheaper unit than otherwise.

The Cap Horn wind-vane steering has (had?) a rather neat facility to operate in this way (and with the autopilot below decks), in addition to its normal wind-vane operation. The Cap Horn also lends itself to being installed offset from the boats centre-line in boats with, e.g., a transom-hung rudder.

 

[srm]

There is a potential compromise between conventional wind-vane steering and an electric autopilot.

As far as I can see from the photo it is the dinghy on the back on the boat is the main issue preventing installation of conventional wind-vane steering. The dinghy is in the position that the wind-vane itself would normally go, and any other location nearby would be out of clear wind.

However, a servo-paddle set up could be installed on the transom under the dinghy, and this could be controlled by an electric autopilot (in turn referenced to either magnetic headings or, by using the input from a wind direction instrument, the apparent wind. The electric autopilot would only angle the servo-blade, while the servo blade would be doing the hard work of actually turning the rudder. In this way the electric consumption would be a tiny fraction of that were the autopilot operating the rudder itself, and the electric autopilot could be a much lower powered, smaller and cheaper unit than otherwise.

The Cap Horn wind-vane steering has (had?) a rather neat facility to operate in this way (and with the autopilot below decks), in addition to its normal wind-vane operation. The Cap Horn also lends itself to being installed offset from the boats centre-line in boats with, e.g., a transom-hung rudder.

Yes, On a previous boat I had the original Windpilot with vertical axis windvane driving a balanced rudder. As the hull and rig was well balanced this was a simple and very effective gear. I fitted the smallest Autohelm to drive the rudder when motoring, and again it worked very well. The auxiliary rudder did not lift like most servo pendulums so was always in the water ready for use.

On my previous boat I used the same set up to work the wind vane on the Monitor gear as an experiment. The ball joint for the end of the tiller pilot was fitted to the counter weight. It worked well but would only really be of use to me for motoring. However, Monitor advise lifting the servo paddle when motoring to avoid excess wear from the prop wash vibrations in the gear. When I moved the Monitor to my present boat I did not add the tiller pilot as I also had a wheel pilot for motoring.

However, from my experience a Monitor gear with the vane moved by a tiller pilot may well suit the OP's boat. But again the rig/hull combination must be in balance as the servo pendulum has limited throw. Electric power drain will be minimal as all the power to turn the rudder comes from the water flow over the pendulum paddle.

A simpler (and probably lowest cost) alternative would be to make a semi-balanced auxiliary rudder driven by a tiller pilot. (like my old Windpilot or the Hydrovane gear). Fitted at the end of the hull it will exert a strong lever effect. Power drain will be a bit higher than the servo paddle set up, but no where near that of a proper autopilot driving the main rudder. Set the boat on course and balance the sail plan, lock the main rudder which will look after any weather helm, then the auxiliary rudder and tiller pilot is just acting as a trim tab to maintain course. I fitted a "fence" at the waterline on my Windpilot rudder to break any low pressure cavitation sucking air down the blade and greatly improved its effectiveness.

 

[Supertramp]

Much here already about balancing the boat. What sails, how much sail, how to set each sail will all matter. You have a joy of a rig to do it with.

Once balance is in control, you should be able to lash the helm when on the wind and she will hold a course. Usually needs the main let out a little more than the jib(s) so it loses power first. I can sail for hours on a fair or fresh wind like this with the helm lashed in one position, although I have a mizzen and fewer jibs. Off the wind is much harder, especially in quartering seas and I resort to autopilot (and lose the mizzen).

Decide then what sort of sailing you will do. If coastal day sails, find a simple solution (tiller pilot?). I like the suggestions of Little Sister/SRM.

If offshore/oceans are your goal you probably want the dinghy off the stern anyway and fit an ocean worthy system. I have often wondered if it could be done while retaining davits, but I suspect not at least with a servo system.

 

[srm]

If offshore/oceans are your goal you probably want the dinghy off the stern anyway and fit an ocean worthy system. I have often wondered if it could be done while retaining davits, but I suspect not at least with a servo system.

Probably not with an "off the shelf" system, but if modified so the wind vane head could be mounted above the level of the dinghy with an extended linkage to the servo paddle gear it could be possible. It's often just a single push-pull rod taking the motion from one part of the gear to the other. Weight and inertia of the linkage would need to be taken in to account though as if too heavy it could reduce sensitivity in light airs.

 

[Supertramp]

Probably not with an "off the shelf" system, but if modified so the wind vane head could be mounted above the level of the dinghy with an extended linkage to the servo paddle gear it could be possible. It's often just a single push-pull rod taking the motion from one part of the gear to the other. Weight and inertia of the linkage would need to be taken in to account though as if too heavy it could reduce sensitivity in light airs.

Thanks. I had thought the same, especially with a counter stern allowing mounting forward of the dinghy drop. It's also got to clear the mizzen boom or the mizzen boom prevented from fouling the vane. Although less of an issue on a long passage on a constant course.

And there's the swim platform....

 

[srm]

I moved my swim/boarding ladder to the side, under the guard rail gate so it folds up into that space, when fitting the Monitor. Changing the shape of the vane could help clear under your mizzen boom. Otherwise an unintended gybe may cause some damage. I think the Monitor supplies a different vane for such installations.

 

[B27]

I'd suggest researching 'sheet to tiller' steering.
The AYRS book on self-steering is worth a read.

There would seem to be two separate problems with an older style boat.
One is the balance of the rig, weather helm etc, the other is the balance, or lack of, on the rudder, meaning force on the tiller is high for a given amount of 'steering moment' from the rudder.

Self steering of the vane or sheet variety is very nice when actually sailing, but in terms of enabling singlehanded trips, you may need an electronic autopilot while motoring or setting sails etc.