autopilot to windvane?
 

I have an autohelm windvane which is the type that has a big rudder with a
little rudder aft to move the big rudder which turns the boat.
I'm thinking I could mount some sort of autopilot to the little rudder to
steer the boat as my regular AP is TU. Does this sound reasonable? Does
anyone know of such a device? Any ideas how to do it?
Gordon

--

Ask not for whom the terrorist bell tolls; it tolls for thee, and thee, and
thee--for decent, innocent people everywhere.

On Sun, 11 Sep 2005 08:32:17 -0700, "Gordon"
wrote:

I have an autohelm windvane which is the type that has a big rudder with a
little rudder aft to move the big rudder which turns the boat.
I'm thinking I could mount some sort of autopilot to the little rudder to
steer the boat as my regular AP is TU. Does this sound reasonable? Does
anyone know of such a device? Any ideas how to do it?
Gordon
It should be feasible but remember that the small servo rudder turns
the opposite direction of the rudder so you will have to set up the
actuator to turn the servo left when the boat needs to go right.

Weebles Wobble
(but they don't fall down)

Yes, this has been done by a few with some success.

Most use a small tiller pilot and attach it to the pivot hinge device where
the normal wind sensor vane 'would normally be'. (it won't work properly
unless you remove the wind sensor vane.)

I have tried it on my Aries windvane but it wouldn't work while motoring
because of the proximity of the Aries servo rudder to the trailing edge of
my stern mounted main rudder. The prop wash coming off the rudder varied
considerablily as the main rudder shifted to correct the boat course. This
prop wash just drives the servo rudder 'hard over'.

I have experienced this same problem while trying to use the windvane, in
it's conventional mode, while motor sailing.

If you have an inboard rudder, I don't think you will have any problems, as
I have discribed. I would suggest that the windvane servo rudder should be
in relatively calm wake.

--
My experience and opinion, FWIW
--
Steve
s/v Good Intentions

Steve wrote:
Yes, this has been done by a few with some success.

Most use a small tiller pilot and attach it to the pivot hinge device where
the normal wind sensor vane 'would normally be'. (it won't work properly
unless you remove the wind sensor vane.)

I have tried it on my Aries windvane but it wouldn't work while motoring
because of the proximity of the Aries servo rudder to the trailing edge of
my stern mounted main rudder. The prop wash coming off the rudder varied
considerablily as the main rudder shifted to correct the boat course. This
prop wash just drives the servo rudder 'hard over'.

I have experienced this same problem while trying to use the windvane, in
it's conventional mode, while motor sailing.

If you have an inboard rudder, I don't think you will have any problems, as
I have discribed. I would suggest that the windvane servo rudder should be
in relatively calm wake.


Peter Förthmann mentions doing this in his book "Self Steering Under
Sail" The book address both auto-pilots and wind vanes and discusses
how to use them in combination. The book is available as a free PDF
download at the following URL.


http://www.windpilot.de/en/Se/Service/downen.html


Howard

In s.com Howard Peer writes:

Steve wrote:
Yes, this has been done by a few with some success.

Most use a small tiller pilot and attach it to the pivot hinge device where
the normal wind sensor vane 'would normally be'. (it won't work properly
unless you remove the wind sensor vane.)

I have tried it on my Aries windvane but it wouldn't work while motoring
because of the proximity of the Aries servo rudder to the trailing edge of
my stern mounted main rudder. The prop wash coming off the rudder varied
considerablily as the main rudder shifted to correct the boat course. This
prop wash just drives the servo rudder 'hard over'.

I have experienced this same problem while trying to use the windvane, in
it's conventional mode, while motor sailing.

If you have an inboard rudder, I don't think you will have any problems, as
I have discribed. I would suggest that the windvane servo rudder should be
in relatively calm wake.


Peter Förthmann mentions doing this in his book "Self Steering Under
Sail" The book address both auto-pilots and wind vanes and discusses
how to use them in combination. The book is available as a free PDF
download at the following URL.


http://www.windpilot.de/en/Se/Service/downen.html


It is possible to use an autopilot in the place of a windvane for most
wind steering gears. Sometimes one should remember the first (often
forgotten) law of mechanical engineering: Keep it simple, stupid. Often
abreviated: KISS.

If there is enough wind for the windwane to work, there is no reason to
rig another electronic device to do the job. If you are motoring, you do
not have to save electricity and you can use the autopilot, but in most
cases the autopilot can do the steering by itself, without the necessity
to rig the wind steering gear.

Some people just try to solve problems that do not exsist by making
things more complicated. Of course we still could have a wind
instrument, steering the autopilot, steering the wind steering gear...

Just another point: If you want to have a backup for your windvane, do
not buy something small, but buy one that can really steer your boat.
Rather have two systems, independent of eachother so you can use any of
them anytime you want.

- Lauri Tarkkonen

I was in Costa Rica when my navico autopilot died on me. I ended up
buying an autohelm from a guy who had exactly what you are talking
about. He had about a 48 foot heavy boat and he had a wind vane on the
back. The wind vane worked find in heavy wind but in calm wind or while
motoring through still air, he used the autohelm 2000 to move the trim
tab on his vane to steer the boat. It worked great for him and the only
reason he sold it the autohelm to me was that he was done cruising and
I begged him to death to sell it to me.

The way he had it rigged was with a bicycle cable attached to the end
of the tiller pilot and then the other end was attached to the rudder
tab. The ends of the cable were mounted and the wire was pulled in and
out with the pilot. Without drawing a picture it might be hard to
imagine but it was really a simple deal and as far as I remember, I
think he sailed the boat for several years with that setup and no
problems.

In Derek Weston writes:

We've been using a (somewhat modified) Autohelm 1000 connected to our
Aries for many years now. Our arrangement works well. We use it when
motoring. We also use it when there is sufficient wind to sail but
insufficient for the vane alone to work well ( 4 - 8 knots or so across
the deck for us).

Most use a small tiller pilot and attach it to the pivot hinge device
where the normal wind sensor vane 'would normally be'. (it won't work
properly unless you remove the wind sensor vane.)

We don't remove the wind vane. In conditions where the Autohelm + Aries
arrangement is best, the Autohelm easily overpowers any wind force on
the vane.

If there is enough wind for the windvane to work, there is no reason
to rig another electronic device to do the job. If you are motoring,
you do not have to save electricity and you can use the autopilot,
but in most cases the autopilot can do the steering by itself, without
the necessity to rig the wind steering gear.

As decribed above, there are conditions when we can make useful way
under sail, but the vane alone won't work. The Autohelm 1000 + Aries
arrangement draws much less power than our Autohelm 3000, and so we
prefer it when passagemaking in these conditions as our solar panels
alone can then supply sufficient power for all needs.

Have you tried an extra large (higher) blade for your wind steering
gear?

The "moving parts" for Aries are quite a bit heavier than the comparable
parts of Windpilot, so Aries needs a bit more wind to work than
Windpilot.

The handicap with your system is that you need two different autopilots,
but makes sense in regard of a bit heavier parts of Aries. I installed
an Aries in a friends boat when we visited Cowes some 15 years ago. He
made a bit bigger wane, of course the material must be a bit lighter as
to balance with the counterweight.

- Lauri Tarkkonen

We've been using a (somewhat modified) Autohelm 1000 connected to our
Aries for many years now. Our arrangement works well. We use it when
motoring. We also use it when there is sufficient wind to sail but
insufficient for the vane alone to work well ( 4 - 8 knots or so across
the deck for us).

Most use a small tiller pilot and attach it to the pivot hinge device
where the normal wind sensor vane 'would normally be'. (it won't work
properly unless you remove the wind sensor vane.)

We don't remove the wind vane. In conditions where the Autohelm + Aries
arrangement is best, the Autohelm easily overpowers any wind force on
the vane.

If there is enough wind for the windvane to work, there is no reason
to rig another electronic device to do the job. If you are motoring,
you do not have to save electricity and you can use the autopilot,
but in most cases the autopilot can do the steering by itself, without
the necessity to rig the wind steering gear.

As decribed above, there are conditions when we can make useful way
under sail, but the vane alone won't work. The Autohelm 1000 + Aries
arrangement draws much less power than our Autohelm 3000, and so we
prefer it when passagemaking in these conditions as our solar panels
alone can then supply sufficient power for all needs.

Lauri Tarkkonen wrote:
In Derek Weston writes:


We've been using a (somewhat modified) Autohelm 1000 connected to our
Aries for many years now. Our arrangement works well. We use it when
motoring. We also use it when there is sufficient wind to sail but
insufficient for the vane alone to work well ( 4 - 8 knots or so across
the deck for us).


Most use a small tiller pilot and attach it to the pivot hinge device
where the normal wind sensor vane 'would normally be'. (it won't work
properly unless you remove the wind sensor vane.)


We don't remove the wind vane. In conditions where the Autohelm + Aries
arrangement is best, the Autohelm easily overpowers any wind force on
the vane.


If there is enough wind for the windvane to work, there is no reason
to rig another electronic device to do the job. If you are motoring,
you do not have to save electricity and you can use the autopilot,

but in most cases the autopilot can do the steering by itself, without

the necessity to rig the wind steering gear.


As decribed above, there are conditions when we can make useful way
under sail, but the vane alone won't work. The Autohelm 1000 + Aries
arrangement draws much less power than our Autohelm 3000, and so we
prefer it when passagemaking in these conditions as our solar panels
alone can then supply sufficient power for all needs.


Have you tried an extra large (higher) blade for your wind steering
gear?

The "moving parts" for Aries are quite a bit heavier than the comparable
parts of Windpilot, so Aries needs a bit more wind to work than
Windpilot.

The handicap with your system is that you need two different autopilots,
but makes sense in regard of a bit heavier parts of Aries. I installed
an Aries in a friends boat when we visited Cowes some 15 years ago. He
made a bit bigger wane, of course the material must be a bit lighter as
to balance with the counterweight.

- Lauri Tarkkonen


I probably won't be doing any changes, since what I have works.

After fitting the larger vane, what if any improvement in light wind
performance did you friend notice? People I've spoken to who have done
something similar seem a bit unsure as to whether there was any
noticeable improvement.