STEERING: Hydraulic vs Mechanical Steering for 50ft Trawler

My builder is proposing various steering systems:

1) Manual hydraulic
2) Cable steering
3) Gear/shaft/U-joint mechanical - simple "Z" shape would require a total of three 90 degree turns and a pair of U-joints

My boat has only a pilothouse control station and a 30 inch wheel is easy to accommodate. An autopilot will need a hydraulic cylinder to be mounted to the steering quadrant, which would offer much-appreciated redundancy.

My previous 65ft power boat had cable steering and personally I thought it was fantastic: it offered "feel" and the kingspoke on the wheel never drifted even a fraction of a degree. Very tight. However you certainly could feel friction in the system.

A drive shaft system should have lower friction than the cable but would pass through the cabins belowdecks, and with only 6ft 4in headroom down there the shaft would be obtrusive.

The requirement is for simplicity and dependability. Personally I'm inclined to either #1 or #2.

Some feedback please.

Go hydraulic. Much easier to install hardware and easier to install autopilot.

Another vote for hydraulic. I also think it's the only approach where your helm wheel will stand still when on autopilot. I think with the other approaches when your pilot steers, the helm wheel will follow too. That seems weird at best, and dangerous at worst.

Hydraulic for sure

Yup, hydraulic.

Hydraulic !

What's happening??? I am seeing a unified response, on THIS forum???? where are the proponents of using hemp line (environmentally friendly) and radio controlled servos (hi tech) and telepathy (alien technology) and a BIG tiller instead (old purists), etc....

This is crazy

No Mast said:

What's happening??? I am seeing a unified response, on THIS forum????

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THE TENTH MAN
If nine of us look at the same information and arrive at the same conclusion, it's the duty of the tenth man to disagree. No matter how absurd it may seem, the tenth man must work on the assumption that the other 9 are wrong.

So if I may be the skeptic, the outcast, let me ask… what exactly is wrong with mechanical steering? Where's the weakness? In what way is it not extremely reliable?

1) It costs less to install, so that difference will make up for having to install a hydraulic actuator for the autopilot, therefore cost works out the same.
2) Hydraulics are easier to install. Am only installing one steering system and it's the builder doing it, not me.
3) The wheel spins when the autopilot is on. Yes it does. It's a bit weird but works fine and I never suffered an injury in all those years using it.

Nothing wrong with mechanical steering. If that is what you want, then go for it.

I just like hydraulic better. I don't like the rudder moving on its own when I take my hands off the wheel. Installing an AP is easier with hydraulic, and there are many more options available for hyd AP's.

If you are going to do mechanical steering with hyd AP, then what is the point? You will need a hyd cyl anyway, and have a clutch to disengage cyl from the quadrant.

I have mechanical steering. Wheel chain drives the shaft which runs a honking enormous 90 degree gear box that sits atop the rudder shaft. Stone axe simple.
1 system failure shortly after launch noted in log book (I suspect something was not tightened at the time of install) and other than that it just works. 50 year old boat and about 6000 hours. Auto pilot is chain driven to the shaft.

BryanF said:

I have mechanical steering… Auto pilot is chain driven to the shaft.

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I had a similar setup with my old Wood-Freeman. What type of drive unit are you using? I have been unable to find a modern (non-hydraulic) drive with enough power to move a large rudder properly.

makobuilders said:

I have been unable to find a modern (non-hydraulic) drive with enough power to move a large rudder properly.

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Jefa has a 300 Nm sprocket drive, how much more do you need? Jefa Steering Systems

I have a chain and shaft steering system. After I bought the boat the AP failed and that was my excuse to upgrade. Couldn't find an AP for a 35 yr. old system so was going to install hydraulic system. Then I found that Raymarine had a mechanical drive AP. I installed it and after five years now, not one problem. Just saying. I still like the idea of having a more modern system. But, all the guys I listen to with hydraulics complain about leaks, pump failures while on trips, etc. My AP may quit but the mechanical steering will get me back home.

I would also put in a backup steering system including a backup autopilot and it's own hydraulic cylinder.

Later,
Dan

QB said:

Jefa has a 300 Nm sprocket drive, how much more do you need? Jefa Steering Systems

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That's nice but.....2500 Euros for an electric motor?!!! The Wood-Freeman used the starter from an old Dodge car, $40-60 at the local junker.

One of my boats had shaft, chain and sprocket, mechanical steering. Dead simple, cheap, reliable. All good till I added AP then the wrap-up in the long shaft back to the rudder confused the hell out of the AP and it never would work right. Changed to Wagner hyd, problem solved.

Have chain gear reduction to shaft pittman arm in the dive boat (Bruno & Stillman). With a balanced rudder, there is no easier (least effort) steering. Can literally steer with 1 finger at 8 knots, no cranking a hydraulic pump while docking (single screw). Far fewer failure points than hydraulic. Only thing replaced in 40 years are the 2 tie rod ends twice and the 2 reduction chains (rusty, replaced with nickel plated). The AP is a hydraulic cylinder tied to the rudder arm that uses a typical AP pump. The system has an electric hydraulic valve. Energized, the pump is tied to the cylinder. Deenergized the valve ties the cylinder ports together so that the cylinder moves freely. I run on AP 80% of the time without a problem.

It's an absolutely great system with simple redundancy that I'll never change. That being said, I would never have it in my trawler if it required the shaft running through staterooms with the shaft, universal joints, and bearings turning exposed to guests.

Ted

MY vote is for the cable.

#1 its far easier to repair should a hassle underway happen. Easy enough to have a fly bridge and not spend a week chasing air bubbles. Cost is minor, yet the feel is excellent., Hyd has no feel.

Parts are anywhere , O rings and rebuild kits are not.

#2 a wheel operated auto pilot should cost 1/4 of a hyd package , is far easier to install or repair.

#3 should a repair be required the emergency deck tiller can be used with out going below and attempting to disconnect a bunch of rusty fittings.

KISS , never lets you down.

I'm with you FF.


I've never had a boat with hydraulic steering, so I may not know what I am missing.


But - I have zero problems with my mechanical system. The autopilot drive is mounted directly on the helm wheel (Autohelm 4000). It is a simple system but works perfectly in all conditions over about 2-3 knots in speed. Sure the wheel turns on its own, but I don't see a problem with that.


The helm wheel is light in any conditions. I have great feel for what is happening when in a following sea, but never so much that its a lot of work.


I can fix anything that breaks. I recently picked up a complete spare autopilot (used) for $60, so I'm covered there.
The emergency tiller can be dropped into place and operating in about 30 seconds.


What advantage am I missing out on?

AusCan I agree,
But the ability to stay on course w/o hands on input is very important to me. I love the feel of cable or gear steering and the ability to clock the helm to the rudder so one can come to dead ahead quickly w/o a rudder position indicator. We steer our boat all the time (don't have AP) and almost all the time I'm happy w that but most of the reason is because I can set the helm w just a few corrections and henceforth only occasionally make small corrections to stay on course.

But I love the feedback and feel of mechanical steering. I contemplated installing adjustable springs to make mechanical steering keep a course but decided it would'nt work.

Converted to hydraulic and am relatively happy. But a mechanical steering system mated to a good AP would be excellent.

Edit:
If I was the type of skipper that uses waypoints and follows a straight course the AP would be more attractive.

Boats with a good cable helm can get by with a piece of line to a wheel spoke for quite a while.

FF,
To hold a course w cable steering I was thinking of adjustable springs attached to the rudder horn. One could get sosphticated w remote adjustment controls .. probably cable operated.

Eric, why overcomplicate it? I'd just go as FF suggests, or perhaps use a heavy rubber band on the wheel spoke.
It would work fine until the current angle or wind direction changes.

"One could get sosphticated w remote adjustment controls ".

Velcro is as complex as is required as the side force from a centerline , not angled shaft will stay mostly the same, as constant RPM.

In the "old" wooden days the engine would be offset a few degrees and the helm would be centered at cruise.

No slight rudder drag , and the ability to let go of the wheel at cruise, with out running in big circles..

O C Diver said:

Have chain gear reduction to shaft pittman arm in the dive boat (Bruno & Stillman). With a balanced rudder, there is no easier (least effort) steering. Can literally steer with 1 finger at 8 knots, no cranking a hydraulic pump while docking (single screw). Far fewer failure points than hydraulic. Only thing replaced in 40 years are the 2 tie rod ends twice and the 2 reduction chains (rusty, replaced with nickel plated). The AP is a hydraulic cylinder tied to the rudder arm that uses a typical AP pump. The system has an electric hydraulic valve. Energized, the pump is tied to the cylinder. Deenergized the valve ties the cylinder ports together so that the cylinder moves freely. I run on AP 80% of the time without a problem.

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That is the same system, same boat too, that gave me the problem with the AP as mentioned above. The difference is that my AP was connected to the helm so it had to deal with the wrap-up of that long shaft (pipe) going back to the pitman arm. I think that is what confused the AP. Hated to remove the old system b/c as you said, dead simple and reliable.

AusCan
Yes I agree. I didn't do it. Just put in hydraulic steering. But didn't expect so much friction.

I actually think the best steering system is wire rope and pullys. Chain and sprocket at the helm then wire rope w lots of strands like 7X19 and large dia pullys of bronze w ball bearings. Guides on the long runs could be of some high tech material w very low friction. A quadrant on the rudder shaft .. bronze also.

That would be far more dependable than anything I can think of and as close to zero friction. Not much inertia either. I priced it out for Willy and the cost is sky high. Installation is probably a fussy doing but understandably not high tech. Was running short of time leaving for Alaska so just did the hydraulic and am fairly happy.

When I was very young I built a dirt cheap wire rope system for my 28' OB. Used 7X7 strand 1/16" dia wire and aluminum clothes line sheaves or pulleys that were braced so they didn't move back and forth. Best steering system I ever had. No quadrant so had to use springs to compensate but in practice the springs didn't compress during normal operation because of the very low friction. Very very low friction and absolutely zero play or slop. Very precise steering. It was 100% dependable while I had the boat but obviously not very durable.

But if I had a big trawler like most of you I'd be investigating power steering.

No Mast said:

What's happening??? I am seeing a unified response, on THIS forum???? where are the proponents of using hemp line (environmentally friendly) and radio controlled servos (hi tech) and telepathy (alien technology) and a BIG tiller instead (old purists), etc....

This is crazy

Click to expand...

I disagree with the need to disagree

I'm having discussions with the technical support department of Lecomble & Schmitt for sizing their hydraulic system (manual, not powered). The strange thing is that they comment that if we design the system for 4.4 turns lock to lock, that in their opinion it will be too stiff.

Meanwhile, my last boat (25ft longer, same tonnage, double rudder) had cable steering and was 3.0 turns and I thought it was perfect.

So why would this be, does hydraulic just have that much more frictional losses so that much more effort is required?

I used to command Brisbane river ferries in the 70s 34ft to 45 ft in length and the steering system on those was a tiller on top of the rudder post which was controlled by a long chain down each side of the boat which ran through a pipe heavily greased.

Steering control and feel was great but you had to get used to chain dragging through the pipe each time you changed course.

Of course the boats were all old vintage by the time i joined the service, some were even hand crank to start.

David.

AusCan said:

Eric, why overcomplicate it? I'd just go as FF suggests, or perhaps use a heavy rubber band on the wheel spoke.
It would work fine until the current angle or wind direction changes.

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Quite right. I have what I call rod and chain steering, and love the feel and the simplicity. I can often let the wheel go for quite long periods and balance her helm by where I choose to perch to offset wherever the 2ic is sitting, usually reading. For longer spells and greater certainty a large rubber band from point near top dead centre round the top spoke works well - I call that my Maori autopilot. (As ex-NZder I know the Maori are proud of their improvisations, so not considered politically incorrect to use that term.)

Frankly one regret I have is not having an A/P, and the only downside to fitting to this type of system is the rather heavy price asked for the rotary electric motor and sprocket to link it by chain to the main drive chain, so I could not justify the cost for our boating region and typically not long distances covered. Apart from that, no problem, and the wheel turning with it would not bother anyone.