Advice/Experience of Inboard Autopilot

[ex-Gladys]

Hi all,

I'm just starting to think about the next "big project" (AKA expense!) for Gladys for next winter. She's a heavyish boat (about 8 tons fully loaded) and I want to replace the inadequate belt drive Navico Wheel Pilot 5000 with an inboard Autopilot.

She has a Whitlock Cobra (gearbox and shaft) system, and one of the objectives is to make the autopilot the emergency steering arrangement, as I have none at the moment.

I have looked at Garmin, Simrad/B&G, and Raymarine on the basis that these seem to be the main players, and, having looked at mounting options for the drive at the weekend, am now stumped.

The linear drives (which would be adequate) all seem to be between c. 27-36" long and at the point where the little tiller is I'd be looking to mount the drive in an area which would be extremely difficult to distribute the load.

In addition, most of these devices want to connect to NMEA 2000, and whilst I have a Garmin plotter with 2000 connectivity at the helm, actually running a 2000 cable into the boat would be a nightmare, and all other instrumentation (Tacktick) connects through NMEA 0183.

So questions to be answered:

1. Any ideas about alternative drive units?
2. Do I need to wire this to the rest of the electronics, or can it sort of sit as a standalone Autopilot?
3. Any views on the different manufacturers?

Thanks in advance

 

[prv]

1. Any ideas about alternative drive units?

There are a couple of other companies that make just the drive unit, to interface with the rest of a system from one of the big three. Bit hazy on the names, but "Octopus" rings a bell. They have systems that use a heavy-duty morse cable, so the motor and gearbox can be mounted in a more flexible position which is handy if the problem is lack of space. They will all need a base to push against mounted near the rudder stock though, so you have the same problem of distributing load. Hard to advise on that without seeing the problem situation, but can it really not be sorted by glassing in some suitable plywood structure?

2. Do I need to wire this to the rest of the electronics, or can it sort of sit as a standalone Autopilot?

I only really know the older Raymarine systems, but those could certainly be fitted on their own if you wanted to. You'd still need to run a cable to somewhere near the helm, though, to install the controller, so it's not clear how this would help. You'd also lose functions like steering to the wind or to a waypoint, which are certainly not essential but can be handy.

3. Any views on the different manufacturers?

I believe Garmin don't offer drive units of their own, on the sensible grounds that they are an electronics and software company, not mechanical engineering, so third parties like those I mentioned above can do it better. Maybe that information is out of date now.

Whichever way you go, I would heartily recommend a decent below-decks pilot. I upgraded Ariam's rattly plastic wheel-drive to a proper ram, and it made a big difference to course-holding and convenience of use - plus less clutter and noise in the cockpit.

Pete

 

[jac]

Two considerations for you.

I personally would not want to connect the steering to a plot for example. On a longer passage you would be steering on a calculated compass course, not the GPS derived CTS unless for some strange reason you needed to keep XTE to 0. Can't think why you might want to do that on any pleasure boat. On a shorter passage where tide is not a consideration, would you want the boat changing course at waypoint arrival on it's own? Probably not as it could create a collision risk so if you have to intervene to say yes, change the course, you may as well push the buttons a few more times and dial in the whole change.

Secondly re emergency steering. Be aware that a below decks AP will only be of use if something happens to the wheel / cable that doesn't jam the whole lot. ( e.g. cable getting caught somewhere on it's travels twixt quadrant and wheel) So a useful thing to have but if your main objective is emergency steering then it won't mitigate all risks

 

[Tranona]

Agree with jac about relying on an autopilot as an emergency steering system with rod steering. If the main steering fails you will need to disconnect the rod, although this is true of an emergency tiller also.

The Octopus drive sounds like it would be suitable www.octopuseurope.com There was a write up of an installation in PBO a couple of years ago. The advantage was that it could be mounted where there was not room for a conventional ram. Very similar price to a conventional ram.

 

[aluijten]

Personally, I'm not a big fan of linear drives. From ruggedness point of view the rotational movement is to be preferred.

Having said this I've heard very positive things about the model in the link below. They connect to most electronic boxes.

http://www.jefa.com/steering/products/drives/direct-dd1.htm

 

[LadyInBed]

I have a Raymarine 5000i which is about fifteen years old now. The linear drive, connected to a stub tiller on the rudder stock, is a very powerful bit of kit, so the strength of the mounting shouldn't be under estimated.
I wouldn't want my setup as a stand alone unit, the extra functionality is far to useful, especially if you sail solo.
Sorry, no knowlage of other manufacturers. My Raymarine has been very reliable . . . .
I believe that this setup is accepted by ARC as the alternative emergency steering system, for me it's the main steering system.

 

[ex-Gladys]

Thanks for all the comments, I'll take all that on board during the further research! Both the Octopus and Jefa are interesting, the latter in particular as it's rebadged for the Garmin Class A...

I'm fully on board with the connection to the plotter etc, the main thing is it would be nice to have wind occasionally as well as fluxgate, and it would also be nice to have a helm that will steer in anything other than <F3 under engine only

 

[Ric]

Another manufacturer not mentioned is Lecomble & Schmitt. They have a very good reputation in France and are used on a lot of racing and "TDM" boats. Like the Octopus, they are hydraulically actuated.

I have just fitted a Raymarine linear drive to replace a Raymarine wheel drive and am very pleased with it so far.

As others have said, you will be losing a lot of functionality if you don't have the autopilot integrated with the rest of your system. I mostly use my autopilot in wind-vane mode and it is the only way to use it when sailing close-hauled.

 

[LadyInBed]

it would also be nice to have a helm that will steer in anything other than <F3 under engine only

Mine handled an 8+ hr downwind run in F6 under twin headsails and F6 beam reach with reduced sail. I try not to be out in much more!
I think a lot depends on how you set the response, set high it reacts much quicker to direction changes, but uses more juice.

 

[prv]

Mine handled an 8+ hr downwind run in F6 under twin headsails and F6 beam reach with reduced sail. I try not to be out in much more!
I think a lot depends on how you set the response, set high it reacts much quicker to direction changes, but uses more juice.

Mine got vastly better when I went from wheelpilot to linear drive, keeping the same brain, compass, etc. I think it was to do with the amount of backlash in the system - the wheelpilot motor would have had to make quite a few turns before it had tensioned up the plastic structure, the wheel sprocket, the cables, the quadrant, and finally imparted some movement to the rudder. Whereas the slightest movement of the ram would be translated to the rudder stock through the precisely machined tiller that Col made for me.

Pete

 

[Spi D]

Truth is that Octopus make pumps for most of the others who then rebadge them to their private label.

Factors to consider on hydraulic systems are Ram capacity (ccm) and pump performance because you want it to manage full stroke movement in 8 to 14 seconds (approx). That is from full stb to full port rudder movement.

Now, the pump performance relates directly to the pump power consumption hence the AP computer ability to supply/control amps which in it's turn has a deciding effect on the price. Head and fluxgate compass might be the same regardless of this.

 

[pvb]

Personally, I'm not a big fan of linear drives. From ruggedness point of view the rotational movement is to be preferred.

When I sold my old HR352 a couple of years ago, the Autohelm/Raymarine Type 1 linear drive was 24 years old and was still working smoothly and quietly. It's an excellent bit of kit, which is probably why they haven't changed it for so many years.

My new boat has a Jefa linear drive, which seems fine too.

 

[sailorman]

When I sold my old HR352 a couple of years ago, the Autohelm/Raymarine Type 1 linear drive was 24 years old and was still working smoothly and quietly. It's an excellent bit of kit, which is probably why they haven't changed it for so many years.

My new boat has a Jefa linear drive, which seems fine too.

My 6000+ and Type 1 is now almost 17 yrs old & apart from a clutch issue dealt with under warranty, its been faultless. well recomended.
Fully integrated with raytheon plotter & GP 30

 

[jonjo]

My thoughts...

I have used the term is "under-deck" rather than inboard in the past.

After sailing 10 years without my Autohelm 6000 intergated with electonic plotting, I find that using main brain to bridge the two keeps me sharp and alert.

As to other data integration, I think I would miss wind data with the associated autotack function. Today was first day serious sail of the season for me and I had forgotton the key press combination for autotack which was sorely missed as I tacked 10 times between the Needles and Hurst sailing solo.

Wheel attached autopilots are fairweather toys compared to a good underdeck ram installation.

Does your rudder stock have a machined key slot for the autopilot tiller? I ask because I cannot imagine that a clamp on a circular stock would be sufficient.

 

[jonjo]

Personally, I'm not a big fan of linear drives. From ruggedness point of view the rotational movement is to be preferred.

Having said this I've heard very positive things about the model in the link below. They connect to most electronic boxes.

http://www.jefa.com/steering/products/drives/direct-dd1.htm

You should substantiate this contrarian opinion.

 

[prv]

Does your rudder stock have a machined key slot for the autopilot tiller? I ask because I cannot imagine that a clamp on a circular stock would be sufficient.

Mine is just clamped on. There's no keyway, so my plan was to have a set-screw with a conical end going into a small dimple drilled in the stock. Col persuaded me that this wasn't necessary, and indeed so far it has not been. Unbalanced spade rudder on a 34' boat.

Pete

 

[LadyInBed]

Does your rudder stock have a machined key slot for the autopilot tiller? I ask because I cannot imagine that a clamp on a circular stock would be sufficient.

My stub tiller came with a pointy pimple on one side of the stock U clamp.
The U clamp was a very tight fit when torqued up, it hasn't moved in its 15 odd years.

 

[Ric]

View attachment 56491View attachment 56492View attachment 56493

My boat has Goiot steering. The Goiot quadrant comes with a casting especially made for a linear drive. The pictures show how I mounted the linear drive in the cockpit locker, with the ram passing through a tunnel to the quadrant.