Redundant autopilot, best option?

[Oceansailor]

In my expearance it is much more common that boats looses steering because of failure in the steering system (between wheel and rudder) than actually rudder failing.

All emergency steering tillers etc. will not work in any kind of weather. They are no more than EMERGENCY steering devises that in best case help you keep the boat pointing in the right direction +/- 30 degrees.

An powerful Autopilot on a separate tiller arm will let you continue more or less as nothing happened.

[stormalong]

I have two autopilots, one modern Raymarine (now 10 years old) And one Autohelm, 1985 vintage. They are set up hot switchable to the Autohelm type 2 long mechanical drive. The drive itself is wired via a four prong generator plug so it can be replaced relatively quickly - about 10 minutes.

The switch I used between the two autopilots and the drive is similar to the standard generator/shore power transfer switch common in many boats.

For a long time I was checking marine resale shops for spares for my old Autohelm. I have quite a supply now.

In my 19 years and 130,000 miles of sailing I have gone through a few course computers and a lot of drive gears.

When they finally upgraded to a bronze gear in the type 2 drive the failure rate dropped to zero.

Now that I only sail summers in the Pacific Northwest I probably have a lifetime supply of autopilot parts.

[seandepagnier]

Originally Posted by mikedefieslife

Here's another option. Pypilot, using a raspberry pi, ...

IMO the most likely method of failure in a modern pilot will be overheating the hydraulic pump, so carry a back up of that too (if your steering is hydraulic).

The pypilot controller supports an optional temperature sensor for the hydraulic motor/pump and you can set the temperature limit.

Originally Posted by stormalong

For a long time I was checking marine resale shops for spares for my old Autohelm. I have quite a supply now.

Yes, I did the same, and tested about 8 different old tillerpilots with pypilot. All of them work, but the ones with ball-screws are more efficient, and can handle rougher conditions.

For a wheel drive, a windshield wiper motor cost $6 from junkyard (they aren't worth much because they never burn out and so aren't needed for parts) and can drive a wheel with a 4:1 to 8:1 belt reduction.

Pypilot. Why not? The cost is so low and with a larger H-bridge can drive the largest drives available. So it's $200 for the Pypilot with H-bridge

The reason for the high cost of pypilot ($150 hydraulic controller) is the quantities are low It takes a lot of work to build a single high power controller, and the parts cost a lot more in low quantities.

As far as what raymarine and others charge: They are not very honest, since they are charging a price of about 10x what it actually cost them to produce their goods. Normal business is 4x, but I am much lower than this for pypilot

Their prices should be dropping as the electronics to do the same or better becomes cheaper every year. Only the drive units hold value over time and even those should not cost much for what they are.

I am hoping in the near future to be able to build tiller pilots with more reliability and maximum efficiency, and using brush less motors with fully open designs as well as many other plans. I hope to get a 3d printer working on my boat soon.

I continue to develop pypilot. Already the software has many options and capabilities surpassing other autopilots. I hope to implement machine learning in the near future to greatly improve it in many ways. For now manual tuning produces good results.

[Oceanride007]

Seems no body else has suggested it.
But a Tiller pilot mounted on a the Emergency tiller would be a good get you safe option for some.
Am thinking of Simrad TP32, don't know if there are more powerful units, never used one but I think they come with their own Brain just need to be set up with a power supply and pivot points.
As a point of redundancy the only thing that is common with the installed steering system is the Rudder.
Of course being underpowered you would have to have the sails reasonably balanced.

[GILow]

For my money I'd go a windvane WITH a tiller pilot backup on the windvane itself. So something like a Hydrovane will do 90% of the work you need, and when the winds are light the tillerpilot can be connected to the hydrovane emergency tiller in place of the windvane.

Covers you in the event of a total steering system failure in addition to using bugger all power and saving wear and tear on your main steering system.

A separate autopilot system on the main steering is just a vulnerable as the first to a main steering failure.

Having said this, can't remember having seen a hydrovane on a cat, but I can't see why it wouldn't work.

[model 10]

[QUOTE=GILow
Having said this, can't remember having seen a hydrovane on a cat, but I can't see why it wouldn't work.[/QUOTE]

Well cats don't sail very close to the wind anyway so having the vane gear on the wrong side would make that even worse.
Man, the tiller pilot addition to a wind vane works so good. I've stopped using an electric job. I did burn out a motor in a tiller pilot once, that cost $60.

[GILow]

Originally Posted by Ecos

Well cats don't sail very close to the wind anyway so having the vane gear on the wrong side would make that even worse.
Man, the tiller pilot addition to a wind vane works so good. I've stopped using an electric job. I did burn out a motor in a tiller pilot once, that cost $60.

Ah right, that explains it. Expensive... but one on each side maybe? Or find one of the models that support a remote vane placement?

Or, just a single one in the middle. Use it with the vane when the conditions suit, and with the tiller pilot at other times?

[roland stockham]

One point to consider is that windvanes tend to be good in the opposite conditions to when electric pilots are at there best. They also don't require power. The most likely electrical failure is not the A/P it is the battery/charging system that powers it so unless you also carry a second power source and a backup battery a spare A/P does not give you full replacement. For ocean crossing I like to see a boat able to sail with no electrics other than the battery powered backups. The other thing is that the 'backup' A/P is the crew, hand steering 1000m gets to be a pain but it works.

[seandepagnier]

my windvane oar broke off (stainless pipe failed) off namibia which has short steep waves. Wind was 25-35 knots and I had to go 200 miles to next port. Windvanes can fail in bad ways and in my case I was unprepared and unable to fix it.

Just a few minutes later, I was ok. The simplest backup is elastic cord. It is very simple, and I have a friend that sails everywhere, crossing pacific ocean and more this way on his catamaran. I can rig sheet to tiller to auto steer in all conditions upwind, downwind, and 35 knots downwind, but would work in much more. It has significant tradeoffs but should be strongly considered for backup.

Originally Posted by roland stockham

One point to consider is that windvanes tend to be good in the opposite conditions to when electric pilots are at there best.

I crossed 3 oceans with only wind vane, you don't need electric autopilot at all. This is a real option to consider as well. I did develop a free software electric autopilot and I don't use the wind vane anymore, it's not as efficient in light wind, and running down wind, but I prefer sailing with it in stronger winds off shore rather than watch electric motor work hard, but I avoid it because I need to keep testing the autopilot and make it better.

If you have a wind vane, you can have a much weaker electric autopilot and maintain most of the advantages. If you drive the wind vane with an electric motor, you really can have a tiny electric motor, but the reaction time has lag, the performance isn't as good, and the amount of power to steer the main rudder already isn't that much.

Typical tiller pilot is ill-suited for this task, although it works, it is far from optimal, but it's worth considering since it can work.

They also don't require power. The most likely electrical failure is not the A/P it is the battery/charging system that powers it so unless you also carry a second power source and a backup battery a spare A/P does not give you full replacement. For

Not from what I have seen. From what I have witnessed, the most likely failure is the autopilot drive unit somehow. From the belts breaking, the toothed sprockets wearing out, the hydraulics leaking, and in tiller pilots, the simrad type are defective by design, and the magnets slip out of place smashing their own hall sensors (which smarter electronics don't even need anyway) and also in tiller pilots, since the brain is in the drive, if even a little water gets inside it stops working. Then wiring corroding in various connections involved. I'm sure other points of failure exist, but this is what I recall.

Never heard of electric failing to the point you can't even power an autopilot, but I'm sure it is also possible.

[boom23]

I've crossed the Pacific with a Lagoon 450 and spent 3 seasons cruising. I had the factory installed autopilot system and few autopilot backup parts (hydraulic ram, hydraulic ram rebuild kit & oil, and second control computer). There is a limit of how many spare parts one can take and I had a lot...

I had to professionally rebuild the autopilot ram in New Zealand. I found metal particles in the oil again and had to discard it and use the spare one.

If you keep an eye on the autopilot pulleys, cables, etc., I believe the ram is the most common part that fails.

When I was preparing the L450 for the crossing, I was not aware of the CPT setup. If it is strong enough for the L450 and has good reputation, it looks like a good backup setup. I would consider it.

On my next boat, I am specifying a second separate and independent autopilot system. It is an option and I want to make it easy for myself.

[Doublewammy]

I was once asked what I thought was the most important spare part I have on board my catamaran, I replied my spare Raymarine auto pilot, all still in box, which was the newer model of the one we had but one day installing beats ten days sailing without one.

[seandepagnier]

Originally Posted by boom23

When I was preparing the L450 for the crossing, I was not aware of the CPT setup. If it is strong enough for the L450 and has good reputation, it looks like a good backup setup. I would consider it.

CPT is great if you like to steer a wide S course using obsolete technology (floating compass with light sensors) and a drive motor based on a windshield wiper motor that you could instead buy for a few $ from a junkyard, then I would say go for it. Would sure beat hand steering.

[akopac]

Will this work with an old benmar autopilot drive unit like this?

https://www.cruisersforum.com/galler...ageuser=188351

[slug]

Originally Posted by Oceanride007

Seems no body else has suggested it.
But a Tiller pilot mounted on a the Emergency tiller would be a good get you safe option for some.
Am thinking of Simrad TP32, don't know if there are more powerful units, never used one but I think they come with their own Brain just need to be set up with a power supply and pivot points.
As a point of redundancy the only thing that is common with the installed steering system is the Rudder.
Of course being underpowered you would have to have the sails reasonably balanced.

Yes indeed

Via the emergency tiller compensates for all auto pilot system component failures and takes up no space in the aft peak

You have a truly independent steering system

If you use this system make sure that you can physically bolt , clamp the emergency tiller to the rudder stock head

Since the lever arm may be short you might put on your thinking cap and devise a way to generate more leverage

[sengland]

Hi there. I know you posted this 3 years ago but am hoping you might still have the Autohelm 4000. I need the clutch lever with the 'D' shapped hole in the end. Might you be able to sell me that or the whole unit? Working or not.
Thanks
Stuart