autopilot installation on 42 ft sailboat

[shadowdancer]

I plan on using an octopus ram, B&G for the computer, rudder feed back, GPS (I have a Vulcan 7) not sure I need a GPS also a wind sensor and compass, and keyboard (again not sure I need compass or keyboard with Vulcan 7) B&G is very hard to contact and not sure they know

does this sound ok ?

[coopec43]

It would be nice to think I'll be asking the same questions as you shortly as I intend installing an autopilot on a 43ft yacht.

There's a fair bit on YouTube re B&G autopilots. Maybe a few clues there?

https://www.youtube.com/results?sear...26+G+Autopilot


Clive

[Frankly]

Not familiar with the steering arrangement on your yacht. If practical to couple the drive system to the steering shaft vice the rudder shaft there will be a significant energy savings in the operation of the AP system. It has to do with how the polar moments of inertia are reflected through a gear or mechanical ratio.


Frankly

[shadowdancer]

I have a Edison wheel steering with cables , the end of the shaft is square to hold the emergency tiller

[Spindrift NH]

Here’s how mine is attached. Looks like an arm manufactured by Edson was added below the quadrant to which both the ram and position sensor was attached.

[Frankly]

Tying the drive unit to the rudder shaft is the more typical arrangement and from the photos your only practical opion. My comment was just to point out if you could drive from the wheel end then there are significant energy savings to be had.

Just ask any of the wheel pilot crowd (CPT for yachts your size) how little energy their APs consume.

On my IP32 with the Edson thru the legs rack and pinion setup and a chain drive off the aft end of the steering shaft, my stereo uses more energy (with Jimmy Buffet turned up a bit) than the AP in typical sailing conditions.

Frankly

[shadowdancer]

do you have a 7" or 12" ram. ?

[tarian]

Just finished fitting a linear drive Auto pilot on 42 ft boat
you will need HUB , (I installed Raymarine ) rudder feedback, Electronic compass (fluxgate) Control head or through your MFD
if using linear Drive you will need a linear Ram (Jeffa is good I got mine from Brittish company) and a steering Quadrant if not already got one , again Jeffa supplied mine

HUB Raymarine EVO 2 connected to ram up to 18 tonnes (boat 12 tonnes )and Compass and 2 P70s control units as I use A tablet for Navigation
I did not feed in wind Direction or Speed , nor any thing else I just want the boat ot go were I say

[Bill O]

Originally Posted by shadowdancer

I plan on using an octopus ram, B&G for the computer, rudder feed back, GPS (I have a Vulcan 7) not sure I need a GPS also a wind sensor and compass, and keyboard (again not sure I need compass or keyboard with Vulcan 7) B&G is very hard to contact and not sure they know

does this sound ok ?

Somewhere in the mix you will need a hydraulic pump also and maybe that was mentally included w/the octopus ram.
Not to sound like a broken record, but we didn't go w/an expensive "name brand" AP and went w/a more cutting edge pypilot. We have rudder feedback, a 9-axis IMU, redundant GPS sources (in case one drops out), AIS input, wind/speed/depth input, an independent hydraulic pump controller and dual stations that can independently control the AP. Basically everything you listed above (and maybe more), all run on a energy efficient Raspberry Pi.

Here are the links on how we set up our nav. computer and the pypilot.
More good news is you don't need to be a computer expert to set up a RPi. Again fairly straight forward by downloading openplotter (free shareware) that has the AP software (pypilot) already embedded.
We've been running our set up for a while now and working well.


Bill O.

[skipmac]

I installed a Simrad/B&G autopilot on my Pearson 422. Before and after the purchase I contacted tech support several times and had no problem reaching an engineer every time, usually they answered but once I left a number and got a call back in minutes.


You will need a compass. A wind sensor is not necessary but can be very useful. For a compass I highly recommend the Precision 9. For the computer/power unit I recommend going with the NAC-3 over the -2. The -3 has more power and the barn door rudder of the Pearson needs it in some conditions.


Just the trip from FL to MA and the AP worked like a charm. Used very little power and kept a better course than I could.

[Bill O]

Originally Posted by skipmac

I installed a Simrad/B&G autopilot on my Pearson 422. .....

You will need a compass. A wind sensor is not necessary but can be very useful. For a compass I highly recommend the Precision 9. For the computer/power unit I recommend going with the NAC-3 over the -2. The -3 has more power and the barn door rudder of the Pearson needs it in some conditions.

Skipmac,
Just curious why you would suggest the higher amp capacity of the NAC-3 if the max. amp draw was matched up to your pump size. Did you have overheating issues? Going off of memory, but I believe the NAC-2 has a 20 amp controller, while the -3 has a 30 amp.
I guess we too have a barn door rudder which I feel its good for dead down wind runs, but that design discussion is for another time. Will say our controller was probably over designed for our large hydraulic pump w/more amps than needed, excessive heat dumps and possibly better board design to reduce heat build up. We have heat sensors on both the controller and the pump motor, but the controller temp usually is only a few degrees above air temp.
So far very happy w/the pypilot AP and typically are on very low gain settings to easily steer our boat w/very low power draw.


Bill O.

[skipmac]

Originally Posted by Bill O

Skipmac,
Just curious why you would suggest the higher amp capacity of the NAC-3 if the max. amp draw was matched up to your pump size. Did you have overheating issues? Going off of memory, but I believe the NAC-2 has a 20 amp controller, while the -3 has a 30 amp.
I guess we too have a barn door rudder which I feel its good for dead down wind runs, but that design discussion is for another time. Will say our controller was probably over designed for our large hydraulic pump w/more amps than needed, excessive heat dumps and possibly better board design to reduce heat build up. We have heat sensors on both the controller and the pump motor, but the controller temp usually is only a few degrees above air temp.
So far very happy w/the pypilot AP and typically are on very low gain settings to easily steer our boat w/very low power draw.


Bill O.

I chose the NAC-3 for two reasons. First, Simrad only rates the NAC-2 for boats up to 35'. Of course as we both must know, rating an AP based on boat length is not exactly valid as it doesn't account for a host of other variables like whether the boat has a balanced or semi-balanced rudder or barn door, if the boat is a high performance boat that will surf and other factors that will effect how much force and turning speed is required to safely steer the boat.

Second, I consider an AP one of the most important bits of equipment on the boat and follow the philosophy of over specing all the components.

Based on the manufacturer's rating and my preference for conservative ratings of the components the NAC-3 was the obvious choice for me.

My only point in mentioning the barn door rudder is that they do require more power to turn that a balanced or semi-balanced rudder. One previous boat I owned had a semi-balanced, skeg hung rudder that I could steer with two fingers except when it started surfing downwind that took a bit more work.


By the way, I am using a Raymarine mechanical linear drive and have no hydraulics in the system.


Also quite interested in the PY pilot and might set one up as a backup.

[Bill O]

I did look up the specs for a NAC-2 and they are only rated at 8A continuous w/16A peak. Agree, would not consider this to be adequate for a primary AP on a 42' sailboat. The -3 was rated at 30A continuous w/50A peak. Quite a jump in power capability between the controllers.

Bottom line for some one doing an initial AP set up is to look at the specs of the AP components and size/purchase appropriately. Too many these days want a plug n' play. w/o understanding the "system" nor how taxing certain sea states or points of sail play into power needs of the AP.

We have a larger below deck hydraulic pump for our AP that could spike at 30A if/when it hits the rudder stop full over (never does). So after looking at the -3 specs it could have worked. One of the turn offs for the Simrad system was the noisy pump as someone described as sounding like "copulating cats" while running and I certainly didn't want to hear that in the aft cabin. Instead we went w/a Kobelt pump (used on Amels) w/silent feet (anti-vibration pads) under the mounting plate and is virtually silent.

Going w/the pypilot was a simple decision as we already had the RPi (the computer) w/ocpn then just needed a controller. The parts are much cheaper than the name brand and so far very reliable. Will agree the AP is a vital piece of equipment and typically we would carry spares to keep such vital systems running. Due to the expense of just the NAC-3 computer alone, I'm doubting many would carry one as a spare in case that failed. IMO the pypilot modular components are so inexpensive one could carry all replacement electronic components and swap them out as needed.

In general, very pleased w/the pypilot as our AP which has many great features (as much or more than the name brand) and functions well. It's also comforting to know that my AP computer in the near future will not be "discontinued" or "not supported" just to sell/upgrade you the latest/greatest.


Bill O.

[skipmac]

Originally Posted by Bill O

I did look up the specs for a NAC-2 and they are only rated at 8A continuous w/16A peak. Agree, would not consider this to be adequate for a primary AP on a 42' sailboat. The -3 was rated at 30A continuous w/50A peak. Quite a jump in power capability between the controllers.

Bottom line for some one doing an initial AP set up is to look at the specs of the AP components and size/purchase appropriately. Too many these days want a plug n' play. w/o understanding the "system" nor how taxing certain sea states or points of sail play into power needs of the AP.

We have a larger below deck hydraulic pump for our AP that could spike at 30A if/when it hits the rudder stop full over (never does). So after looking at the -3 specs it could have worked. One of the turn offs for the Simrad system was the noisy pump as someone described as sounding like "copulating cats" while running and I certainly didn't want to hear that in the aft cabin. Instead we went w/a Kobelt pump (used on Amels) w/silent feet (anti-vibration pads) under the mounting plate and is virtually silent.

Going w/the pypilot was a simple decision as we already had the RPi (the computer) w/ocpn then just needed a controller. The parts are much cheaper than the name brand and so far very reliable. Will agree the AP is a vital piece of equipment and typically we would carry spares to keep such vital systems running. Due to the expense of just the NAC-3 computer alone, I'm doubting many would carry one as a spare in case that failed. IMO the pypilot modular components are so inexpensive one could carry all replacement electronic components and swap them out as needed.

In general, very pleased w/the pypilot as our AP which has many great features (as much or more than the name brand) and functions well. It's also comforting to know that my AP computer in the near future will not be "discontinued" or "not supported" just to sell/upgrade you the latest/greatest.


Bill O.

Have had discussion before with boaters experienced with hydraulics in general and AP drives specifically and noise was mentioned several times. One very experienced boater commented that hydraulic systems were simpler than mechanical but I don't quite understand how that could be. Both need an electric motor but mechanical has gearing while the hydraulic has pumps, lines, etc.


My boat came with a Raymarine AP that was non-functional including the drive but new brushes and new bearings fixed the drive and I tossed the rest. The drive was the Type 1 which is rated max to about my boat displacement so when I saw a old but unused in the box Type 2 on eBay I grabbed it for a spare. Good thing since the old drive died after 24 hours under sail on my trip north. Anyway, I'm very happy with the Ray linear mechanical as it has plenty of power and is very quiet. Quiet is critical for me since the motor is right under the bed in the aft cabin.

[edmundsteele]

Having a wind direction input to your auto-pilot is very useful and worth the extra effort of “hooking up” the option, simply because you can set a constant angle to the wind. You can use this on long passages so that you don’t have to adjust the sail trim during the night. (There is often an alarm that tells you that the wind has swung “too much” and you need to adjust course). If you are soloing or your partner is asleep, you can use the auto-tack facility to tack the boat by yourself. If you get into bad weather you can set the auto-pilot to head up a couple of degrees in the gusts and then back it off to “close hauled” during the lulls. If the weather really sucks and you heave to, you may be able to set the “heave to” wind angle on the autopilot to help the trim.
Ed