How does CapeHorn
often asked at boat shows how the CapeHorn Self-Steering
gear compares with MONITOR.
always avoided commenting performance, as I did not want to lose my
precious credibility making statements on matters I have no direct
experience of, as all the self-steering gears I have ever used were of
my own design. However, I can quote the words of Guy Stevens,
who has experienced both gears ;
subject of self-steering gear, here is what he wrote
a blog in
which he commented on the equipment he had
used on his boat Pneuma
(the bold type is ours) :
"Monitor Windvane - HMMM. This is a
tough one to write about. It almost works all of the time. It will only
steer the boat if it is underpowered, and trimmed for neutral or a
slight bit of lee helm. It has steered for at least 6,000 miles. We use
it a lot, and swear at getting everything just the way that it wants so
that it will steer. I vacillate a lot on whether I would purchase one
again or just put a really good autopilot instead.
It will always be the way it works,
steering an S-shaped course; it won't sail the boat if she is perfectly
tuned for speed, and if the boat should catch a gust or a wave that
pushes her around it won't compensate quickly enough, and requires that
you steer the boat back onto the course and then set everything up
again. Lots of the cruisers out there have had significant problems with
the welds on their units: something that Scanmar has been quick to send
replacement parts for in most cases, but it is still a huge hassle
waiting for and getting replacement parts through customs in far-off
In June of 2002 I had the opportunity to take
Jemima, a boat with an almost identical underbody, to
Pneumas from New Zealand to Tonga. Having just completed the
installation of a Cape Horn wind vane
on Jemima, we used it extensively
on the trip. I found the Cape Horn to be superior in all respects to
the Monitor. It was easier to adjust course, steered a straighter
course, was less sensitive to balance issues, delivered more power
to the steering apparatus, looked neater, and was much simpler in
operation and construction.
However, there is more to say about our
relative solution to the problem of making a boat seer itself. I
generally try to dismiss the matter by saying that being a generation
apart, they do not really compare. The first Hasler gears gears had a
vertical axis windvane driving the servo-pendulum he had invented.
First generation. Then Marcel Gianoli introduced the
quasi-horizontal axis vane, soon adopted by all : Monitor, Windpilot,
Sailomat, Aries, Navik ... Second generation. But those gears
are an afterthought, an add-on bolted to the transom, steering through
lines over the deck to the wheel. The CapeHorn 'philosophy' is
that a voyaging boat should be made to steer itself with a system which
is as much part of the boat as the mast, sails or engine The
CapeHorn self-steering is integrated into the boat and into its
steering system. Third generation.
happened to pick up a MONITOR sales brochures at a recent boat show and
thought I could do the exercise of comparing our respective solutions. The text in blue is quoted
from the MONITOR brochure.
first MONITOR windvane was made in 1975 in the garage of a retired
Southern California engineer. Scanmar started selling windvanes in 1977
and purchased the MONITOR project in 1981 when only a few hundred vanes
had been produced. Scanmar brought practical knowledge to the business,
based on a 1970-76 circumnavigation that the current owner Hans Bernwall
and his sailing partner had done with FIA their 40 ft Alden cutter. In
those days, there was no windvane on the market that fit their boat and
they had to make their own. After considerable time and expense, the
result was an auxiliary rudder system with a trimtab.
means MONITOR, which does not use an auxiliary rudder and trimtab, is a
different vane than the one Hans Bernwall and his partner
started cruising under sail in 1963 and immediately became interested
in making a boat steer itself. In
1968, I built a gear for my first boat, a 24 ft sloop (vertical vane
driving a Hasler-type servo-pendulum) and used it in my first
single-handed passage. I purchased my Alberg 30 Jean-du-Sud in
1973 and built a second self-steering gear (horizontal vane driving an
auxiliary rudder) that steered a few passages between the East Coast and
the West Indies, then across the Atlantic. In 1978, I was in France,
and I started preparing my boat and myself to sail back to Québec
single-handed and non -stop. However, I would not sail directly : I
would make a big detour through the Southern Ocean and around Cape
Horn. I was well aware that such a voyage would
require a super-heavy
duty self-steering gear.
learned by experience that my present auxiliary rudder would not work in
the Southern ocean, only a servo-pendulum driving the main rudder could
control a boat in long downwind runs. I spent considerable time on the
design, built a prototype in aluminum, tested it, then had it copied in
stainless steel and sailed out of Saint-Malo Sept. 1, 1981. I did not
make it non-stop, I was capsized and dismasted in the Southern Ocean ;
but after splicing the mast and refitting, I completed the voyage
Gaspé, Québec, May 9, 1983, having sailed 28,200 miles in 282 days.
this voyage, I never had to steer : the gear I had designed kept
Jean-du-Sud on the required course on all points of sail, as
soon as there was enough wind to sail, as long as I could carry sail –
and even under bare poles. I never had to reef or alter optimum sail
trim to make it easier for the self-steering. Under jury rig, it was
this test, I judged my prototype could be offered other sailors. I
named it CapeHorn and
in July 1989, created CapeHorn
chapter of the MONITOR brochure describes the principle of the
servo-pendulum and explains how this is better than other self-steering
systems. It also mentions the fact that windvanes and autopilots
complement each other, the autopilot being
used in calm, and the windvane steering as soon as the wind blows.
totally agree with this.
with tiller or wheel steering
control lines led to the boat’s steering gear? On tiller-steered boats,
similar in both systems : the lines are led to the tiller at a distance
which provides a ratio of 2 : 1 between lateral pendulum tilt and
rudder angle : for a pendulum tilt of 10°, both want a 5° rudder angle.
The pendulum lines are connected to the MONITOR
wheel adapter which is made of stainless steel ... [
CapeHorn control lines
wrap around individual grooved Delrin
cylinders fastened to the spokes of the wheel and
placed at such a
distance from the hub that the ideal ratio of 2 : 1 between
servo-pendulum tilt and rudder angle is arrived at.
lines in the cockpit be avoided?
they can, but in our opinion, lines in the cockpit are necessary with
the servo-pendulum gear and the disadvantage is very slight. Keep in
mind that with the MONITOR doing all the steering, you do not spend much
time at the helm where the lines are! (…) WE STRONGLY ADVISE
AGAINST GOING INTO THE LAZARETTE HOOKING THE LINES UP DIRECTLY TO
THE QUADRANT OR A SHORT TILLER UNDER DECK.
upper-case and bold type are theirs. Here, I am afraid Hans Bernwall
overstretches his credibility when he hides the fact that CapeHorn
has been doing precisely this for over twenty-five years.
normal tiller installation, the pendulum lines should be attached 20 –
30 inches from the rudder shaft
(2 : 1 ratio). If you go inside
the lazarette, you might find room for a 10-12" long tiller but obviously
you can not steer a big boat with such a short tiller. In order to get
enough power, you would have to include some sort of purchase system. If
you add a myriad of blocks you will introduce a lot more friction which
is bad for performance. You also use up valuable storage space and
operation of the vane will probably be difficult.
a myriad, Hans, only one per control line! Remember the CapeHorn
Self-Steering is integrated into the boat, with the servo-pendulum
trailing behind the boat linked (through a tube bonded to the hull) to a
quadrant inside the lazarette. If you lead the two control lines coming
from this quadrant through two blocks fastened on the boat’s steering
quadrant (or disk, or auxiliary tiller…) at a distance (from the
rudder axis) equal to the radius of the CapeHorn quadrant,
you automatically obtain the ideal 2 : 1 ratio, this single block
doubling the force and halving rudder angle.
then lead those lines to a pair of jamming cleats located within reach
of the helm. To connect the self-steering, pull the two lines tight and
jam-cleat. To disconnect, yank the lines free. To adjust for any
weather or lee helm on a given point of sail, pull one line tighter.
cases, connecting the lines internally requires fewer blocks than
leading them over the deck to a drum on the wheel (not to mention the
fact that any pre-existing cables and sheaves between the wheel and the
rudder quadrant contribute considerably more friction when the force of
the pendulum is transmitted to the rudder through the wheel than they do
when the force of the pendulum drives the rudder stock directly,
bypassing the wheel), which means better performance. If a little space needs to be
up, CapeHorn believes it is better
used up in the
lazarette than in the cockpit.
With a CapeHorn, lines in the
cockpit can be avoided.
Construction and transmission mechanism
gears are built of 316L stainless steel. Except the MONITOR
transmission gears are Silicon Bronze.
MONITOR gear set consists of the pinion gear (top) and the ring gear (bottom).
The gears are designed with a feedback mechanism to prevent the MONITOR
from over steering and “fish tailing”. The maximum correction happens
when the gear is in neutral position. When the pendulum swings to the
side, the rotation of the pendulum is gradually decreased.[
main technical problem in designing a self-steering gear is to transform
the vertical movement of a connecting rod coming from the vane, into the
rotating movement of the servo-pendulum stock, which will cancel itself
as the stock tilts laterally (to avoid “fish tailing”). The “Southern
California engineer" who made the MONITOR retained the obvious solution
: gears, made of bronze. I am no engineer, but I felt that there could
be a more elegant solution. After experimenting with different systems
for more than a year almost full-time, I came up with a single piece of
bent ¼” stainless steel rod with several precise bends in it. First, two
90° elbows at its aft end form a crank. The up-and-down motion of the
vertical connecting rod that descends from the vane is transformed by
this crank to a rotary motion of the horizontal rod. Then, further
forward, the horizontal rod assumes the shape of a “Z”. The central
branch of the “Z” passes through a slot in the stock of the vertical
servo-pendulum blade. As the tilting vane moves the connecting rod up or
down, the rotating crank causes the central branch of the “Z” to move
out of its initial fore-and-aft orientation, which in turn rotates the
pendulum about the vertical axis of its stock. This permits the flow of
water past the servo-pendulum to tilt the pendulum very powerfully about
a horizontal axis. It is the strong force of the tilting pendulum that
turns the rudder, and it continues to do so until the vane loses its
tilt and brings the central branch of the “Z” back into a fore-and-aft
When the pendulum swings to the side, the
rotation of the pendulum is gradually decreased.
CapeHorn : When
the pendulum swings to the side, the rotation of the pendulum falls to
zero. The rudder correction is absolutely proportional to the tilt of
the vane and course variation.
MONITOR airvane pivoting unit has two sets of delrin ball bearings in
stainless steel races. The pinion gear has two sets of delrin roller
bearings and the pendulum shaft has top and bottom delrin roller
bearings in stainless steel cups. These bearings make a tremendous
difference especially in difficult windvane conditions, which is light
air and downwind when the apparent wind is very weak. The airvane has
very little power in these conditions and friction in a windvane will
CapeHorn reduces friction at the source : our transmission mechanism
has fewer parts and all bearing surfaces are polished ¼” dia. stainless
steel rod on UHMW bushings. The servo-pendulum stock is polished
stainless steel inside Teflon bushings. This absence of bearings does
not seem to affect light air, downwind performance, as CapeHorn
is the only self-steering gear in the
capable of steering downwind in light air, with the main to one side
and a reacher to the other, and there is
no pole holding the clew of the
reacher or genoa.
ZThis performance is documented in last images of
the (multiple award-winning) film With Jean-du-Sud Around the
World : filmed first from a plane, then closer from a powerboat,
Jean-du-Sud sails into the bay of Gaspé under that precise sail
combination ; when it is rocked by the wake of the powerboat,
the sail does not collapse ; the gear capable of such performance had
just steered 28 000 miles, and the servo-pendulum bushings on the
prototype had been cut from a piece of PVC pipe (they are now Teflon)!
Witness Unmatched CapeHorn Performance
smaller number of moving parts, aside from ensuring superior performance
and making breakage less likely, allows us to offer the CapeHorn at a
Installation on different boats
provides different mounting arms to mount their gear on different types
individual CapeHorn gear is custom : the model is chosen
according to the type of stern of each boat and it is
built to the
dimensions that will provide the tightest fit.
MONITOR brochure illustrates installations on different types of boats
which I have matched with the CapeHorn solution (the slightly inferior
quality of the MONITOR pictures comes from the fact that they were scanned from their brochure).
who appreciate beauty in yachts have formed their own opinion.
: We strongly believe that an oceangoing sailing boat should not
carry a dinghy in davits. Eventually it will be lost in rough weather.
There is also a conflict between windvanes and the davits.
CapeHorn gear needs only
4 inches of space aft of the boat
and can easily share the stern with davits. On a passage, a prudent owner
would stow the dinghy on deck or below, but a self-steering gear is
also used in coastwise cruising, when davits
are most useful. The photo
illustrates what is impossible with MONITOR or any other vane:
stern, self-steering and davits.
Alternatively, the windvane tower can be located at the
forward end of the
horizontal axle (and built tall enough to pick up the wind above an arch).
have their own Owner’s manual, with detailed instructions for
installation as well as operation.
We estimate that 90% of the MONITORs are installed by the owners themselves and this is encouraged
also true for CapeHorn. Because it is integrated into the boat,
installation looks intimidating, but it actually is easier than it seems
and most users who normally work on their boat perform their own
installation. However, we have installers in various locations and
occasionally travel ourselves to perform installations. In the
season, we have performed installations in New-York, Seattle, Ibiza, Cadix,
Nice, as far as Panama…
strongly recommend all MONITOR owners to carry the MONITOR Spare Part
uses no spare parts : it is built strong and durable enough in the first
place. During the whole 28000 mile voyage through the Roaring Forties,
I did not have to replace a single part on the prototype.
A swim ladder in the
middle of the transom. Can the MONITOR be mounted to the side?
Yes it can, but if you are serious about self-steering and want maximum
performance, we strongly suggest that you move the swim ladder and put
the windvane in the middle where it belongs. You would not have
the mast off center to make room for the dinghy!
was the first to dare install a vane off the centerline. Up till then,
it was believed that a vane needed to be centered. Experience shows
that an offset installation has no noticeable effect on performance. I
installed the CapeHorn gear on Argonauta, a Bénéteau
Moorings 45 in Tortola, BVI, then the boat sailed around the world. The
crew had flown back from Australia when I asked the owner if he had
noticed a difference on performance on either tack, and he answered none
Naturally, whenever possible, it is better to offset a ladder, but boats
with opening transoms can also enjoy the advantages of an integrated CapeHorn installation.
systems come with two vanes. The MONITOR vanes are made of
polycarbonate. The CapeHorn vanes are
unbreakable : the light
air vane is spinnaker cloth inside a 3 mm stainless steel wire frame (it
can only bend) ; the heavy weather vane is aluminum.
If you insist to have an
airvane that fits under the mizzen boom, an optional shorter mizzen vane
is available. In general, we feel that this vane isn't necessary, since
tacking and jibing is "the event of the week" in normal cruising. All
MONITOR vanes can be taken off in seconds and put back after the tack
and when a preventer is on the boom. The standard high aspect airvanes
are more effective than the shorter wider version. If you want to short
tack up a narrow channel, the mizzen airvane could come in handy, but
normally we suggest that you use either the mizzen or the MONITOR.
Hundred of boats with mizzen booms have MONITORS. We do not consider it
to be a problem.
CapeHorn gear being custom-built, the windvane tower can be
made short enough to keep the vane below the mizzen boom (you will be
able to tack up that channel under self-steering). (It can also be made
tall enough to reach clear air over a dodger,
a bimini or an arch).
Electric autopilot hook up
systems allow to control the
servo-pendulum with a small autopilot.
MONITOR the autopilot sits on the pushpit and replaces the vane.
the CapeHorn, the system is built-in : the autopilot is located
inside the lazarette, out of the weather, and connected to the front end
of the co-axial control rod.
Stepless remote course control
systems offer stepless remote control.
MONITOR servo-blade is stainless steel, one size fits all. The CapeHorn blade
is made of fiberglass. To provide adequate power, while keeping
drag to a minimum, the wetted area of each blade is
proportional to the rudder area, also
taking into account resistance in the boat's steering system.
allow to flip the paddle up out of the water when the vane is not
used (MONITOR pivots aft, CapeHorn laterally). Both
are easily removed and stowed below.
: Between the hinge and
the water paddle is the safety tube. This is an inexpensive sacrificial
stainless tube designed to buckle in case of an overload.[
CapeHorn servo-pendulum blade is held locked to its stock by an elastic
link that keeps two notches in its mount in contact with two pins on the
sides of the stock. If the blade hits an obstacle, this assembly comes
apart. No buckled part to replace.
A MONITOR windvane will
take you there, but you do not want to give up your swim platform.
Sounds familiar? The Perfect solution is here...[
systems offer a solution to rudder failure : MONITOR replaces the
servo-pendulum paddle with a larger one that acts as an emergency rudder
;. The CapeHorn emergency rudder is fastened on the windvane tower tube.
could find more differences but those are the most significant.
You can judge which of those two systems offers the most elegant
solution to the problem of making a sailboat steer itself.
not be surprised if Scanmar keeps selling more gears than CapeHorn, they
are more agressive in their marketing, they are located closer to their
market and they need to keep their crew of 7 busy.
CapeHorn crew is two people : My nephew and neighbor Eric Sicotte builds
the vanes, I take care of the rest ; the shop is located in Oka, on the
Northern shore of the Ottawa River behind the houses we both grew up
in. Eric's boat, Irwin 25 Complice, rests on a mooring in front
of his house .
never have gone through the trouble of putting a new product on the
world market if I knew it was just as good as what was already
offered. I launched CapeHorn because I was convinced I had a superior
product : the only way of making that demonstration was to offer it to
other sailors. The first years were rough, but 15 years later, CapeHorn
Marine Products provides Eric and myself with a comfortable living in a
Marketing a Self-Steering gear nowadays mostly amounts to answering
E-Mails. Fortunately, business is quieter in the summer months ; this
is when the CapeHorn Sales Office moves aboard Jean-du-sud
(through wi-fi, cellular, satellite, HF etc), while Eric, not yet of
retirement age, keeps the shop open and sails Complice in home
assured, Hans, our ambition with CapeHorn is not to dominate the world
windvane market, it is only to keep living as we do now.
que ça dure!
Y.G., May 2006
Suite : Quotes from Satisfied CapeHorn