• REMINDER - COVID-19

    Any content, information, or advice found on social media platforms and the wider Internet, including forums such as YBW, should NOT be acted upon unless checked against a reliable, authoritative source, and re-checked, particularly where personal health and liberty is at stake. Seek professional advice/confirmation before acting on such at all times.

    Users who are found to promulgate FAKE NEWS on the forum in regard to this issue, intentional or otherwise, may find their access terminated. It is your responsibility to provide references to bona fide sources.

    FAKE NEWS, in this regard, is that which is posited by organisations, media, etc., that is repeated on the forum, or used to support personal opinion/hypothesis posted by users - FAKE NEWS is not necessarily the personal opinion/hypothesis being posted in itself, any issues with such should be challenged respectfully.

    IN ADDITION it seems that conspiracy theories are finding their way onto the forum. This is not the place for such content. Users who post it may find their access limited or permanently suspended. Please leave it where you find it.

Self Steering Gear on a Catamaran

Steersman

New member
Joined
19 Sep 2013
Messages
59
Location
West Berkshire
Just curious to know, what type of self steering do catamaran and trimaran owners use, and how effective are they for cruising?
:)
 

AngusMcDoon

Well-known member
Joined
20 Oct 2004
Messages
7,309
Location
I know how fast I'm going, but not where I am
Tiller pilot + solar panel. Works fine. Helm is very light as the rudder is so small on a tri-meringue so doesn't use much juice.

One failure in 35k miles when the side if the gearbox inside the tiller pilot broke in a strange way. Repaired with Araldite as a get home fix then replaced the broken part myself.
 

Adonnante

New member
Joined
1 Aug 2006
Messages
365
Location
Millbrook, Cornwall
Autohelm 4000 tiller pilot on a Azuli (38' cat weighing 5 ton). Current system is over 15 years old, internals of the control head were replaced about 10 years ago and we were replacing the rams about every 18 months due to Raymarine's idea on sealing. The problem was solved about 8 years ago by covering the motor/ram joint and ram shaft with cycle inner tube cut to suit, no break downs since. Autohelm is used all the time cruising and at night when racing, I still believe I do a better job! We need to reduce speed to around 8/10 knots when the seas build up as the response isn't quick enough in F6 and above. One of the most important items on the boat, particularly when single handing.

Peter.
 

snowleopard

Active member
Joined
16 May 2001
Messages
33,652
Location
Cornwall
On Snow Leopard I have a hydraulic Autohelm 5000. It does a reasonable job and I rarely steer on passage. Despite many frustrating hours trying to tune it, it still wanders 5-10 degrees either side of the course so not very good to windward. I sometimes hand-steer downwind for a bit more speed as I can anticipate the yaw as a wave passes under us whereas the AH is slow to catch up. I can't steer relative to wind as the rotating mast precludes a masthead wind sender.

My previous tri (40 ft, 3.5 tonnes) had a Gunning pendulum servo wind vane which did a fair job. It had 3 sizes of vane to suit the weather which was a pain as it involved crawling across the aft cabin to change them. It steered via a drum on the wheel. A direct link to a tiller would have been better.
 

Daydream believer

Well-known member
Joined
6 Oct 2012
Messages
11,289
Location
Southminster, essex
I bought my Aeries from the owner of a multihull. He had it for an atlantic crossing but soon found that the acceleration of the boat was far too quick for wind vane operated mechanical systems hence the sale to me.
The point being, that one would need an electrical autopilot
 

Steersman

New member
Joined
19 Sep 2013
Messages
59
Location
West Berkshire
Thanks for the comments. This is all very helpful. We have been asked to design a Steersman for a catamaran, and I just wondered what other people do.

It seems that speed of response and reliability are the main issues.
 

snowleopard

Active member
Joined
16 May 2001
Messages
33,652
Location
Cornwall
Phil Weld lost a tri in mid atlantic due to acceleration - the boat started to surf down a big sea and the acceleration brought the apparent wind forward rapidly. The wind vane put the helm hard over to bring the wind aft and the boat capsized over what had been the windward outrigger. A combination of centrifugal force and a sudden gybe were enough to flip it. Moral - pure wind vane gears are dangerous on light fast multis.
 

Steersman

New member
Joined
19 Sep 2013
Messages
59
Location
West Berkshire
Phil Weld lost a tri in mid atlantic due to acceleration - the boat started to surf down a big sea and the acceleration brought the apparent wind forward rapidly. The wind vane put the helm hard over to bring the wind aft and the boat capsized over what had been the windward outrigger. A combination of centrifugal force and a sudden gybe were enough to flip it. Moral - pure wind vane gears are dangerous on light fast multis.
Hi Snowleopard

While agree with you in a way. The experience you describe is extreme, and I should think most yachties would be in harbour under those conditions. I don't think you can completely rule out windvane systems on the basis of that one experience. Like electric systems, they have their limitations.
 
Joined
26 Oct 2001
Messages
8,570
Location
Portugal
Hi Snowleopard

While agree with you in a way. The experience you describe is extreme, and I should think most yachties would be in harbour under those conditions. I don't think you can completely rule out windvane systems on the basis of that one experience. Like electric systems, they have their limitations.
It is a well known fact that servo windvanes don't work in fast multihulls but slow and heavy cruising ones should be fine.
 

mjcoon

Well-known member
Joined
18 Jun 2011
Messages
3,425
Location
Berkshire, UK
Just curious to know, what type of self steering do catamaran and trimaran owners use, and how effective are they for cruising?
:)
Your home web page would look better with spelling correction of headline "Self Stearing Gear"!

Mike.
 

snowleopard

Active member
Joined
16 May 2001
Messages
33,652
Location
Cornwall
Hi Snowleopard

While agree with you in a way. The experience you describe is extreme, and I should think most yachties would be in harbour under those conditions. I don't think you can completely rule out windvane systems on the basis of that one experience. Like electric systems, they have their limitations.
Can you rule out sailing under gale force conditions - even if the furthest you go is across the channel? I've found myself surfing at 16 knots under autopilot in the North Sea. A heavy cat or mono wouldn't have a problem but a fast multi could easily hit that sort of condition around the British coast.
 

Steersman

New member
Joined
19 Sep 2013
Messages
59
Location
West Berkshire
Hi Snow Leopard

I see your point. My experience is with monohulls so I'm trying to get my head round how a light multihull would perform.

I guess a small lightweight trimaran would be tossed around like a cork, but a larger one would have a degree of stability because of the greater weight, and hence momentum which would tend to keep it on a straighter course.

But in gale conditions steering will still have to be spot on, and done manually I guess. Sailing at night would be even more difficult because you can't see the waves coming and therefore won't be able get the boat lined up before it hits.

Scary stuff, no wonder that boat, you mentioned earlier, flipped. It makes you wonder if it would have made any difference if it was steered manually at the time.

Thank you

Rob
 

snowleopard

Active member
Joined
16 May 2001
Messages
33,652
Location
Cornwall
Point taken

But what about a Steersman? http://www.steersman.net
It appears to be a pre-arranged version of headsail sheet to tiller lash-ups. I imagine it takes a bit of fiddling to get it right for each point of sailing as opposed to vane and electronic types that just need to be switched on. No doubt it would work reasonably well for long passages but you'd need to be prepared to adjust it for each change in wind strength or direction.

A friend had an autopilot failure during an Atlantic crossing so rigged up the sheet of a backed staysail to the wheel and managed to avoid most hand steering for the rest of the passage. I have met others with the same problem who haven't even tried when their autopilot failed and hand-steered the rest of the crossing ending up totally knackered.
 

snowleopard

Active member
Joined
16 May 2001
Messages
33,652
Location
Cornwall
Auto helm driving the wheel. Like another person on board at times.
If you have the option to fit a below-deck version it will be more reliable but probably more expensive.

Mine is a pump plumbed into the hydraulic lines so all I have to do is push the Auto button and take my hands off the wheel.
 

snowleopard

Active member
Joined
16 May 2001
Messages
33,652
Location
Cornwall
I guess a small lightweight trimaran would be tossed around like a cork, but a larger one would have a degree of stability because of the greater weight, and hence momentum which would tend to keep it on a straighter course.
Tris of whatever weight tend to steer like they're on rails, not because of weight but because the long narrow hulls tend to keep going in a straight line. The exception to that is when sailing in a big quartering sea where the different movement of water in the peaks and the troughs result in one end of the hull being washed to port and the other to starboard. A good helmsman can anticipate that but any self-steering gear will be playing catch-up all the time so the boat will yaw a lot more. To windward it's a different story; I lost steering 800 miles offshore in my tri and got back by trimming the sails. She would go to windward for hours at a time with everything pinned in tight.
 
Top