Trim tab wind vane

[Pfeiffer]

I am looking for my next boat and I want a self-steering vane. Does anyone make a simple, auxiliary rudder trim-tab type vane?

My last boat had one. It was homemade, very simple. An auxiliary rudder hung on the back of the boat. There was a vane on top with a direct rod down the trailing edge of the aux rudder with the trim tab attached. Simple, no gears, lines, or anything else. To set the vane for the direction, you just slipped a bolt into one of the notches in a bicycle sprocket. It steered close-hauled, wing-on-wing, etc. all points of sail for a six-month cruise to Mexico and the Sea of Cortez. It steered after I hit a reef that destroyed my rudder!

I definitely want the aux rudder, and the Hydrovane seems like the only option. But it is complicated (relatively) and expensive. Monitors, etc don't have the aux rudder and you have the lines to deal with. Suggestions?

[Jim Cate]

The AutoHelm aux rudder wind vane system, now made and sold by Scanmar, is such a system, more or less.

I designed and built a similar system for our previous boat and it steered us most of the time over 17 years and 86,000 miles of cruising. I miss it!

Jim

[Pfeiffer]

Thanks Jim, I checked out their website. This is basically just what I want. Maybe not as fancy as my bicycle sprocket... I cruised on my old boat when I was younger (and broke). Now, I am retired. probably can't haul in an anchor like I did. But, I can afford a better boat with a windlass! We'll see what happens with this quarantine, maybe I will see you "out there" sometime.

[Jim Cate]

Originally Posted by Pfeiffer

Thanks Jim, I checked out their website. This is basically just what I want. Maybe not as fancy as my bicycle sprocket... I cruised on my old boat when I was younger (and broke). Now, I am retired. probably can't haul in an anchor like I did. But, I can afford a better boat with a windlass! We'll see what happens with this quarantine, maybe I will see you "out there" sometime.

Good one! I hope that it works out for you.

So, where are you located and what sort of boat do you sail ?

This is a hint: please fill out your personal profile with some details about yourself. This info will help us all answer any further questions you may post and will save having to ask for fill ins every time something comes up.

Jim

[jamhass]

Originally Posted by Pfeiffer

I definitely want the aux rudder, and the Hydrovane seems like the only option. But it is complicated (relatively) and expensive.

I had the Hydrovane (recently sold the boat and the Hydrovane was a real asset).

While pricey, it is actually a very simple device that works well and is very reliable (due in part to its simplicity.) I suspect that it's complexity is mainly perceived. It is not easy to visualize how the parts actually work to keep a course.

Remember, all the gears and wheels merely set the angle to the wind. Once set, the link between the vane and rudder are pretty straightforward.

Plus, their mount system is really nice, with few bits and parts that are pretty easy to align.

Just a happy customer.

[CarinaPDX]

The original owner of Hydrovane offered a version that reversed the rotation of the output, and a short output shaft had a tab arm that cross-linked to a tiller arm on a trim tab. I bought one and fabricated a trim tab - it works quite well. The current Canadian sellers of Hydrovanes chose not to offer it so no use for you.

There have been a number of trim tab designs out there, although I guess most are now out of business. I think just searching for "wind vane trim tab" will find them but will require a bit of time.

Greg

[roverhi]

Windpilot makes an auxiliary rudder vane called the Windpilot Pacific Plus. Unlike the Hydrovane it uses a small pendulum servo vane to drive the aux rudder and will steer the boat if there is enough wind for the vane to sense it. Has worked very well on my boat including a downwind sail to Hawaii in wind conditions that were light for that run. Ran DDW most of the way with less than 10k relative wind. I bought it used off a much larger boat that it had steered from the NE, Carribean and up to SF with no problems. Only negative is they are at least as expensive as the Hydrovane.

[Pfeiffer]

I'm confused about the different styles of self-steering vanes. Any comparisons that I find online are just explanations of the different styles, not an opinion of what is better.
The AutoHelm seems the simplest(fewer things to go wrong) and has an aux rudder. Control of the rudder is by the trim tab on the following edge of the aux rudder eliminating the twisting pressure on the post. It is the least popular style, but seems like the best design? Next, the Hydrovane has the aux rudder but is more complicated than the AutoHelm. The servo-pendulum style (Monitor) seems like the most popular, but not sure why. It does not have the aux rudder, it is more complicated mechanically, and you have the lines in the cockpit. This seems like the least desirable style? What am I missing? Thanks

[roverhi]

Pendulum servo vanes are the most sensitive and theoretically the most efficient at steering the boats as long as they are compatible with the boat. They work better with the direct linkage of a tiller but 50' boats with wheels have successfully fitted a Monitor. Couldn't make a monitor work at speeds below 4k because of the very stiff steering of my Pearson 35. It was a PO installation with a lot of 90 degree turns to get the steering lines to the forward mounted wheel. The WindPilot Pacific Plus auxiliary rudder vane turned up so didn't spend any time to try and sort out the steering line routing and/or heavy helm issues. Had an Aries on my W32 and a Windpilot Pacific Light on my Sabre 28. These P/S vanes steer(ed) the boat if the boats were sailing. I hate to steer and motor so the vanes steered the boat about 98% of the time.

Auxillary rudder vanes work more as trim tabs for the boats rudder. Set the boat to balance with the main rudder and the aux rudder makes the small changes to keep it on course. They will sail the boat by themselves but better if used in conjunction with the boats rudder. Negative is maneuvering in reverse and in close quarters. With a full keel boat they will seriously effect turn radius which can make maneuvering into a slip a major challenge. Same goes for reverse. May not be as big a problem for fin keel boats. WPPP steers the boat just fine under sail and connection to tiller pilot to compass steer is easy for really low drain auto pilot.

Of the many Autohelm installations I've seen, there is only one that is/was fully functioning. All the others were in some state of disrepair, demounting or completely off the boat and cluttering up a garage. Don't know if that's because they don't work, break down regularly or mess up slow handling so bad they get taken off. Have not talked with directly with anyone who has/had one. Can also see problems with the trim tab when backing up.

[Adelie]

https://hydrovane.com/

[Pfeiffer]

Thanks for your input. Yes, I am aware of the issue of backing up with an aux rudder. I talked to Hydrovane and they confirmed the issue. They suggested that I(or crew) could steer the Hydo separately when in reverse! I don't like the idea that you cannot easily lift the rudder out of the water.

[roverhi]

Originally Posted by Pfeiffer

Thanks for your input. Yes, I am aware of the issue of backing up with an aux rudder. I talked to Hydrovane and they confirmed the issue. They suggested that I(or crew) could steer the Hydo separately when in reverse! I don't like the idea that you cannot easily lift the rudder out of the water.

I use lines to the wind sensing vane's lead weight to spoof it into steering the WPPP vane. Doing that was about the only way to get the boat's turning radius down enough to get it into the slip. Doesn't help much in reverse though might work better with Hydrovane in reverse.

[CarinaPDX]

Originally Posted by roverhi

Auxillary rudder vanes work more as trim tabs for the boats rudder.

Perhaps a bit of nitpicking but that is not strictly true. A trim tab uses leverage to turn the main rudder (the lever arm is the distance from the trim tab to the rudder post) and as such is able to use very little force to turn a large rudder, which is especially important for unbalanced rudders like the "barn door" on Carina. In contrast an auxiliary rudder (Hydrovane) has no amplification, and in fact is fighting the main rudder to turn the boat. When a trim tab is turned and the rudder moves this reduces the power of the trim tab (but aids damping), whereas a pendulum maintains the same angle to the water flow no matter the angle and is thus the most powerful design. So in order of steering power, high to low, the pendulum is first, the trim tab second, and the auxiliary rudder is last. In most situations this is not an issue as the force from the wind increases as a square of the wind speed so there is usually plenty of steering force in normal to strong conditions, and in fact it is common to use a smaller wind paddle in high winds. It is at the lighter end of the wind scale that the pendulum and trim tabs shine.

Having had to deal with a trim tab for many years I would definitely opt for a pendulum system for a replacement. The ability of the Windpilot and Fleming to rotate the pendulum out of the water when coming into port is a very big advantage, and they are very powerful designs. Both are available with integrated auxiliary rudders for larger boats, but anything under 40' probably doesn't need the power, or the complexity and weight. The Fleming model I saw at the London Boat Show in 2000 was a work of art in precision stainless casting (it was the model made in California). They moved to Australia but I think are now either out of business or under another name. The Windpilot is very similar but made out of aluminum, and I would be very happy with one as well.

There are other smaller manufacturers of wind vanes that sell at lower prices. Search on the forums and you will find other threads where they are mentioned.

Greg

[Jim Cate]

Lots of speculation above about living with a system like the AutoHelm vane. Here's some real life experience:

I designed and built a system that used the same concepts as the AH unit, that is, aux rudder with trim tab driven by, an inclined axis vane via push/pull cables running in teflon tubes. The blade was designed so that it could be lowered in angle in higher winds, just as the original AH design. I made some improvements in the rudder blade shape, in the vane design and in the cable construction. After some experimentation, it drove the boat (a retired IOR one-tonner with fin keel and partial skeg main rudder) for most of the 86,000 miles we logged cruising in her.

The good stuff:
It would steer the boat down to around 5 knots of apparent wind on all points of sail. It managed quite well in storm force winds with the vane tilted down to near horizontal and appropriate storm sails hoisted. It was easy to deploy or strike, and offered easy course adjustment (although I never tried to make a remote means of doing so). Of course, no lines in the cockpit to the wheel and we had the reassurance of practical steering should the main rudder be lost. One final thing: this was an early IOR design, and they had well known issues of being a bit squirrely sailing deep angles at speed. The additional rudder really helped with this when steering manually or under autopilot. She became quite well mannered!

The bad stuff:
It did interfere with low speed maneuverability. If left free to swing, the turn radius wasn't much altered, but then if one needed to back up, it made the boat uncontrollable as it would immediately go to full lock one way or the other. So, I rigged lines that locked it in dead ahead position. Backed up ok then, but the turning radius was badly affected. There were no problems with the trim tab backing up, for it was small in area and quite strong.

Sailing on a broad reach or DDW in large following seas it would yaw quite a bit before correcting. Servo pendulum vanes are much better at this, for there is instantaneous feedback to the pendulum as the boat's stern moves sideways and the rudder response is quite rapid. With my system no correction was applied until the wind vane "noticed" the change in apparent wind direction and moved the trim tab, and then there was additional delay whilst the tab drove the rudder over. The result was a greater degree of course variation than was optimal. The average course made good was correct, but temporary deviations meant that we sailed a greater distance through the water than necessary. This wasn't a frequent problem in practice.

So there you have it... not perfect, but a good and very reliable system that was pretty easy to build as a DIY project.

Jim

[Pfeiffer]

Greg, with the pendulum system, do you have any kind of back up for rudder failure? (I've had a rudder knocked off a full keel boat, and my DIY aux rudder-trim tab, brought me home.)