Autopilots
 

I am looking at installing a new bellow deck autopilot on my 34' sailboat
and I'm looking for opinions.

1, Any thoughts on the pros and cons of mechanical linear drives verses
hydraulic linear drives? My understanding is that the mechanical uses less
power and give better feedback to the wheel when turned off,

2. Raymarine verses Simrad?

John

On Sun, 23 Jan 2005 20:39:49 -0800, "Johnhh"
wrote:

I am looking at installing a new bellow deck autopilot on my 34' sailboat
and I'm looking for opinions.

1, Any thoughts on the pros and cons of mechanical linear drives verses
hydraulic linear drives? My understanding is that the mechanical uses less
power and give better feedback to the wheel when turned off,

2. Raymarine verses Simrad?
====================================

I have a Robertson/Simrad AP-35 with the so called hydraulic linear
actuator. It seems like a pretty solid unit, and with the clutch
disengaged, it has no impact on steering whatsoever. The hydraulics
are completely integrated within the actuator so there are no external
pumps/hoses/resevoirs to be concerned with.

"Johnhh" wrote in message
...
I am looking at installing a new bellow deck autopilot on my 34' sailboat
and I'm looking for opinions.

1, Any thoughts on the pros and cons of mechanical linear drives verses
hydraulic linear drives? My understanding is that the mechanical uses
less power and give better feedback to the wheel when turned off,

2. Raymarine verses Simrad?

John
I've also read that the mechanical drive uses less power. I think this is
because the motor runs all the time with the hydraulic unit.
You will have a lot more options if you go with Raymarine. Just go to eBay
and search for Raymarine autopilot or Autohelm autopilot. Lots of new and
used systems for less $$ than Simrad. Probably an ST5000 control head and
linear drive would be good for your boat. According to the West Marine
catalogue the ST5000 is no longer manufactured so I think there are some
good buys out there on the remaining stock.

I should have said, uses less power when turned on and gives better wheel
feedback when turned off.

Thanks for your response.


"Wayne.B" wrote in message
...
On Sun, 23 Jan 2005 20:39:49 -0800, "Johnhh"
wrote:

I am looking at installing a new bellow deck autopilot on my 34' sailboat
and I'm looking for opinions.

1, Any thoughts on the pros and cons of mechanical linear drives verses
hydraulic linear drives? My understanding is that the mechanical uses
less
power and give better feedback to the wheel when turned off,

2. Raymarine verses Simrad?
====================================

I have a Robertson/Simrad AP-35 with the so called hydraulic linear
actuator. It seems like a pretty solid unit, and with the clutch
disengaged, it has no impact on steering whatsoever. The hydraulics
are completely integrated within the actuator so there are no external
pumps/hoses/resevoirs to be concerned with.

Thanks Gordon, I am looking at new units. ST6000+ and AP16

"Gordon Wedman" wrote in message
news:4jbJd.49008$06.29501@clgrps12...

"Johnhh" wrote in message
...
I am looking at installing a new bellow deck autopilot on my 34' sailboat
and I'm looking for opinions.

1, Any thoughts on the pros and cons of mechanical linear drives verses
hydraulic linear drives? My understanding is that the mechanical uses
less power and give better feedback to the wheel when turned off,

2. Raymarine verses Simrad?

John
I've also read that the mechanical drive uses less power. I think this is
because the motor runs all the time with the hydraulic unit.
You will have a lot more options if you go with Raymarine. Just go to
eBay and search for Raymarine autopilot or Autohelm autopilot. Lots of
new and used systems for less $$ than Simrad. Probably an ST5000 control
head and linear drive would be good for your boat. According to the West
Marine catalogue the ST5000 is no longer manufactured so I think there are
some good buys out there on the remaining stock.

John:

I have used both a Raymarine ST6000 with a rotary electric drive and a
Simrad/Robertson AP11 with a hydraulic drive. There was no significant
difference in power consumption. The hydraulic drive (with an integral pump)
only runs the pump when it needs to. If I watch the ammeter, I see about 1-2
amps normally and it jumps up to 3-5 amps when the pump kicks in. The linear
electric drive does about the same.

In general, hyraulic pumps and cylinders are pretty robust and probably are
less prone to failure. As others have said, with the hydraulic system
disengaged, there is very little drag on your steering. Mounting a self
contained hydraulic actuator is no different than a linear electric
actuator.

The Raymarine has a better user interface and I think, a better algorithm
for dealing with various sea states and imbalanced helm conditions.

So my vote would be Raymarine electronics with a hydraulic actuator.

David

Thanks David,
my information on the "feel at the wheel" came from a Raymarine rep. and
Simrad documentation. I have no first hand knowledge, but suspect it is a
fairly minor difference. The mechanical drive may use just as much juice,
but I have convinced myself that it less. I was less concerned about the
durability thinking that if I were doing heavy duty use of an autopilot,
that it would be with a Monitor windvane and not the electrical anyway. I
have also heard that the Raymarine "may" have better wind algorithms and I
am experienced with their wheel pilot and very comfortable with the user
interface. I ordered the Raymarine today.

"David&Joan" wrote in message
news:DRkJd.438$Jt.39@fed1read02...
John:

I have used both a Raymarine ST6000 with a rotary electric drive and a
Simrad/Robertson AP11 with a hydraulic drive. There was no significant
difference in power consumption. The hydraulic drive (with an integral
pump)
only runs the pump when it needs to. If I watch the ammeter, I see about
1-2
amps normally and it jumps up to 3-5 amps when the pump kicks in. The
linear
electric drive does about the same.

In general, hyraulic pumps and cylinders are pretty robust and probably
are
less prone to failure. As others have said, with the hydraulic system
disengaged, there is very little drag on your steering. Mounting a self
contained hydraulic actuator is no different than a linear electric
actuator.

The Raymarine has a better user interface and I think, a better algorithm
for dealing with various sea states and imbalanced helm conditions.

So my vote would be Raymarine electronics with a hydraulic actuator.

David

Johnhh wrote:

Thanks David,
my information on the "feel at the wheel" came from a Raymarine rep. and
Simrad documentation. I have no first hand knowledge, but suspect it is a
fairly minor difference. snip

The comment about hydraulic systems having less feel may have been in
reference to a hydraulic primary or hand steering system as compared to
a mechanical hand steering system.

In a hydraulic steering system the helm is mounted on the shaft of a
pump or directly coupled to a pump with a loop of chain. That is a
closed loop system with a cylinder that pushes or pulls (depending on
which way the helm/pump is turned) on an arm on the top of the rudder
post.

The "feel" of helm movements is lost in the high mechanical advantage of
a hydraulic system. It can be rendered further imprecise by factors
such as the presence of any pockets of air trapped in the system and any
weep against pressure that occurs in the pump or cylinder.

Properly installed and maintained, a hydraulic hand steering provides
very little or no feedback at the hand to turning forces. It feels like
power steering did on older (1960's or so) American cars, no change in
turning forces from lock to lock. Newer cars have variable ratio power
steering that gives an impression of feedback with turning forces that
increase as you get further away from the neutral position.

If you have ever steered a boat with hydraulic steering that is badly
worn or has pockets of air in the steering loop, you'll never forget it.

Your autopilot, hydraulic or electric, is trying to maintain a heading
and will normally push and pull the same arm on the rudder post that
your manual steering does.

If a linear drive has any clutch slippage or hydraulic weepage the
course computer will make frequent to nearly continuous steering inputs.
The rudder wants to fall back to center and the AP keeps working to
steer to the set heading. If that happens you'll see it on an ammeter
as David describes.

Jack

--
Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
(also receiving email at jacker at midmaine.com)

"Jack Erbes" wrote in message
...
The "feel" of helm movements is lost in the high mechanical advantage of
a hydraulic system. It can be rendered further imprecise by factors
such as the presence of any pockets of air trapped in the system and any
weep against pressure that occurs in the pump or cylinder.

Properly installed and maintained, a hydraulic hand steering provides
very little or no feedback at the hand to turning forces. It feels like
power steering did on older (1960's or so) American cars, no change in
turning forces from lock to lock. Newer cars have variable ratio power
steering that gives an impression of feedback with turning forces that
increase as you get further away from the neutral position.

Mmmm...., I have a hydraulic system and I can feel the propeller blades pass
the rudder when turning and when I am in very shallow water, the steering is
much heavier. No feedback eh?

Meindert

I have sailed on a 35ft motor sailor with manual hydraulic steering and
there was a lever on the wheel pedestal that you could shift to (somehow)
get feedback to the wheel. Otherwise, as described by others, there is
little or no feedback..

The skipper advised that we leave the feedback "off" for some reason and I
never tried it. One thing I did notice was, there was no reference to "wheel
center" in relation to center rudder. Without doing too much exploring, I
assumed that there was some slippage in the system (since it had done a
circumnavigation and more during it's 20+ years).

However, I believe that a manual hydraulic system should have feedback if
properly set up and maintained. I also believe that these systems offer a
good alternative to cable systems when the wheel must be at some far/remote
location.. I would assume that there are hydraulic AP systems that can be
integrated into an, otherwise, manual hydraulic system .

My opinion and experience, FWIW.

Steve
s/v Good Intentions
"Jack Erbes" wrote in message
...
Johnhh wrote:

Thanks David,
my information on the "feel at the wheel" came from a Raymarine rep. and
Simrad documentation. I have no first hand knowledge, but suspect it is
a fairly minor difference. snip

The comment about hydraulic systems having less feel may have been in
reference to a hydraulic primary or hand steering system as compared to a
mechanical hand steering system.

In a hydraulic steering system the helm is mounted on the shaft of a pump
or directly coupled to a pump with a loop of chain. That is a closed loop
system with a cylinder that pushes or pulls (depending on which way the
helm/pump is turned) on an arm on the top of the rudder post.

The "feel" of helm movements is lost in the high mechanical advantage of a
hydraulic system. It can be rendered further imprecise by factors such as
the presence of any pockets of air trapped in the system and any weep
against pressure that occurs in the pump or cylinder.

Properly installed and maintained, a hydraulic hand steering provides very
little or no feedback at the hand to turning forces. It feels like power
steering did on older (1960's or so) American cars, no change in turning
forces from lock to lock. Newer cars have variable ratio power steering
that gives an impression of feedback with turning forces that increase as
you get further away from the neutral position.

If you have ever steered a boat with hydraulic steering that is badly worn
or has pockets of air in the steering loop, you'll never forget it.

Your autopilot, hydraulic or electric, is trying to maintain a heading and
will normally push and pull the same arm on the rudder post that your
manual steering does.

If a linear drive has any clutch slippage or hydraulic weepage the course
computer will make frequent to nearly continuous steering inputs. The
rudder wants to fall back to center and the AP keeps working to steer to
the set heading. If that happens you'll see it on an ammeter as David
describes.

Jack

--
Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
(also receiving email at jacker at midmaine.com)

On Tue, 25 Jan 2005 09:41:24 -0800, "Steve" wrote:

I would assume that there are hydraulic AP systems that can be
integrated into an, otherwise, manual hydraulic system .

==============================================

Yes, commonly available. One advantage to adding an autopilot to a
manual system is that you usually gain a rudder angle indicator in the
process.

On 2005-01-24 15:39:49 +1100, "Johnhh" said:

I am looking at installing a new bellow deck autopilot on my 34'
sailboat and I'm looking for opinions.

1, Any thoughts on the pros and cons of mechanical linear drives
verses hydraulic linear drives? My understanding is that the
mechanical uses less power and give better feedback to the wheel when
turned off,

2. Raymarine verses Simrad?

John

I replaced a Navico (Simrad) with a Raymarine S1 (ST6001+ control head
+ S! controller and pump). The boat had mechanical steering but a
hydraulic actuator and pump. This was original with the boat and I saw
no need to replace it. The pump motor runs only when the computer wants
to make a correction. The system works well. Plus I have the spare
Raymarine hydraulic pump. I purchased online from the US and saved a
bundle over what Raymarine's distributor wanted for the same thing here
in Australia. Easy to install and works well so far (nly 4 months use).

--
Regards,
John Proctor VK3JP, VKV6789
S/V Chagall

My understanding is that when you are steering manually, the hydraulic fluid
bypasses the pump so you can turn the wheel freely. When you turn on the
autopilot, a solenoid is used to close off this bypass. It draws about 1
amp and is always on when the pilot is on whether the pump is running or
not. I do not know the mechanical drive accomplishes this, but the power
usage figures for them are lower.


"John Proctor" wrote in message
news:2005012614393516807%lost@nowhereorg...
On 2005-01-24 15:39:49 +1100, "Johnhh" said:

I am looking at installing a new bellow deck autopilot on my 34' sailboat
and I'm looking for opinions.

1, Any thoughts on the pros and cons of mechanical linear drives verses
hydraulic linear drives? My understanding is that the mechanical uses
less power and give better feedback to the wheel when turned off,

2. Raymarine verses Simrad?

John

I replaced a Navico (Simrad) with a Raymarine S1 (ST6001+ control head +
S! controller and pump). The boat had mechanical steering but a hydraulic
actuator and pump. This was original with the boat and I saw no need to
replace it. The pump motor runs only when the computer wants to make a
correction. The system works well. Plus I have the spare Raymarine
hydraulic pump. I purchased online from the US and saved a bundle over
what Raymarine's distributor wanted for the same thing here in Australia.
Easy to install and works well so far (nly 4 months use).

--
Regards,
John Proctor VK3JP, VKV6789
S/V Chagall

I installed a Nexus linear drive (AP 2000) unit on our Tayana 37. Am very
pleased with the performance and operation. I elected not to put in a
bulkhead mounted instrument but instead used just their remote unit with
16' cable so I vcan move around in the cockpit or go below and operate the
unit.

Jerry

"Johnhh" wrote in
:

I am looking at installing a new bellow deck autopilot on my 34'
sailboat and I'm looking for opinions.

1, Any thoughts on the pros and cons of mechanical linear drives
verses hydraulic linear drives? My understanding is that the
mechanical uses less power and give better feedback to the wheel when
turned off,

Lionheart has a B&G electro-hydraulic autopilot. The ram drives the
bellcrank on the rudder post, directly, and will steer the boat unless the
rudder falls off during complete failure of her steering gear. It is very
powerful and will steer her rudder under just awful conditions. With
inputs from a B&G compass, B&G's Wind instrument and our NMEA network, it
can be steered by compass, like a windvane or by The Cap'n software on the
computer via NMEA 0183 network everything is hooked to.

Unless you are laying right on top of it in the aft cabin of the ketch (39'
Amel Sharki), you can't hear it running. In the cockpit, observing the
wheel, it looks as if a ghost is steering her as there is total silence.
The unit has been zero trouble since it was installed last year.

It draws about 12 amps peak current, but only when the drive motor is
working hard. The motor completely shuts down when the ram stops moving
the rudder and only comes on slowly to move the ram slowly, controlled by
its own computer box located on the boat in the aft passageway. Average
current is much less, depending on sea conditions, of course. Lionheart
has lots of DC power.

Calibration amounts to running the wheel to the port stop, pressing a few
buttons to tell the computer "This is the port stop", then running it to
the starboard stop and pressing the buttons again, then centering the
rudder and pressing the buttons again. Compass calibration amounts to
turning two slow circles out in the harbor until the display tells you it's
calibrated.

The B&G constantly calibrates itself under use, varying its drive
parameters as it "learns" how the boat reacts to rudder input. After a few
hours of use, say making a 90 degree turn, the turn coordination is
perfect, the wheel coming back to center just as the new course is
attained. It's a really nice unit.


2. Raymarine verses Simrad?


I'm just replacing my 3rd Raymarine 2KW radome. The other two were so
cheaply made they all corroded up inside from condensate water. I don't
think we'll be buying more Raymarine gear in the future.....

Larry W4CSC wrote:

Lionheart has a B&G electro-hydraulic autopilot.

Anyone on that boat have a license to use the DSC radio?
Bwahahahahahahahahahah

In article ,
Jetcap wrote:

Larry W4CSC wrote:

Lionheart has a B&G electro-hydraulic autopilot.

Anyone on that boat have a license to use the DSC radio?
Bwahahahahahahahahahah

All Vhf DSC Radios are covered by the Blanket Nationwide
FCC Station License for all noncommecial vessels that navigate
soley inside US Waters. No Operators License is required under
the Blanket Nationwide FCC Station License.

Bruce in alaska
--
add a 2 before @

Bruce in Alaska wrote:

No Operators License is required under
the Blanket Nationwide FCC Station License.

Then Larry should be relieved he won't need that GMDSS Operator and
Maintainer ticket he claimed to hold and was needed for anyone to
operate a DSC radio.

He was gone long enough to get one of the guys at West Marine to teach
him about GMDSS but the FCC still only admits to him holding a ham ticket.

I wonder who operates the HF station on Lionheart ... neither Larry or
the owner holds a ticket. This is why Larry vanished for so long, he got
caught claiming he held a stack of licenses that the FCC somehow can't find.

It's hard to believe he has the balls to show up here again. I wonder
how long it will take him to start claiming all kinds of licenses again.

Rick

Bruce in Alaska wrote:

There is a GIANT difference between a GMDSS Radio Suite and a VHF
Radio with DSC builtin. If you don't know the difference, then you
need to educate yourself. Licensing is just a small part of that
difference.


Tell that to Larry ... that is what started the thread that ended in his
withdrawing in shame after falsely claiming to have a bunch of licenses
he doesn't hold. He was claiming that anyone using a VHF DSC radio was
required to hold a GMDSS operator ticket.

In case you have forgotten, look at the "Modifiying Icom" thread of last
July.

Rick