Hydraulic Steering

[NoTies]

The trip up from Wellington highlighted some issues with my mechanical steering (totally worn out). It has given some minor symptoms recently so I thought I'd pull it apart & check and was surprised by the sorry state of it. The steering head which is the cause of the problem is a heavy duty Teleflex type system that is no longer manufactured and there is nothing suitable to replace it with as all the Teleflex systems are a lot lighter.
I am strongly considering a hydraulic retrofit due to the limited installation room I have and I also like the idea of replacing the wheel drive pilot I have with a reversible pump out of the way below deck & a lot quieter.
Question, I have a spade rudder (no skeg but very strong 2" solid rudder stock,well supported with bearings) If I fit check valves to the system I can use the pump system for the pilot, it won't turn the wheel when operating and the rudder will effectively be locked by the helm position in following seas etc. As far as I understand, if I don't fit check valves I won't be able to use a pump for the pilot and will still have to use the belt drive. Spade rudders are vulnerable but are most of the failures caused by the rudder being slammed over from side to side by the seas or are they caused by the rudder being held firm by the helm and having to absorb the energy of the seas?
I know I won't have much feedback with a check valve system but I am a lazy sailor and try to do most of my coastal cruising without having to stand at the wheel all day.

[Rick]

Hydraulic steering systems can be installed with a bypass to the check valves if you want both features. At a minimum I recommend using a good helm pump with integral check valves (usually the balls in the check valves can be removed later if you desire to have continuous feedback) and a bypass valve. The bypass valve is handy when you are cleaning the bottom and want to move the rudder whilst in the water.

It is a myth that there is no feedback with the checkvalves installed. Think about it. The force required to move the rudder is a function of the number of turns of the wheel to get lock-to-lock of the rudder, the radius of the wheel, and the force you apply to the radius of the wheel with your arm. It is impossible to turn the rudder without feeling the force required. The more water force against the rudder the more power it takes either by an autopilot or your body to quickly move that rudder, hence you HAVE feedback.

I used to have the check valve bypass on another boat. I did not use it because it was so much easier to turn the wheel to trim the boat heading, take my hand off the wheel and not have the boat turn due to any residual weather or lee helm or a turbulence in the water against the rudder. This is a nice feature that most sailboaters are afraid of because of this myth that one cannot have feedback with hydraulics per se, or check valves in particular. Such people probably have not had much experience with a good hydraulic installation. Anyway, I converted my present boat to hydraulic steering to eliminate the backlash or give that cable steering systems all have (if you attempt to remove the backlash then you wind up with a very stiff friction-full wheel response) and to provide a platform amenable to installing a real autopiliot.

Make sure that you plan carefully the geometry of the hydraulic ram, the ram "tiller" arm, and the ram size. The ram attachment to the hull must be VERY robust to be reliable. If you use the new Teleflex prefabricated hydraulic lines and their hydraulic fittings you will have the best chance of having zero leaks due to their design using "O" rings in addition to the normal sealing features of the usual fittings. In addition, the lines are much easier to install without kinking than copper tubing.

Do not be afraid of mixing brands of hydraulic gear: you might opt for a variable ratio helm pump by Kobelt, a hydraulic expansion tank by Hynautics, hydraulic ram by Capilano or Hynautics (or Kobelt), tubing by Teleflex and autopilot by Furuno, for example.

Start by picking a ram that is strong enough, and more, for your rudder. That establishes the ram volume (you will use only a balanced cylinder). That volume then establishes the helm pump volume. Calculate that you need to have a turns ratio between 3 to one and 5 to one (max for a sailboat in my opinion) and, therefore, a 13 cubic inch displacement ram requires a helm pump displacement of 13/3 cubic inches per turn for a 3 to one turns ratio which equals 4.33 cubic inches. An adjustable helm pump that has 2.6 to 4.33 inches per turn (or a range wider than this) will give you the ability to set between 3 and 5 turns lock to lock. Similarly, a calculation will establish the autopilot pump size and speed. Figure that for offshore work steering downwind in a heavy following sea that sufficient power is needed to turn lock-to-lock in about 7 seconds, depending upon your boat response to the rudder angle.

Keep in mind that most autopilot recommendations are made for vessels in relatively tame conditions and, therefore, are too slow for serious offshore work under all conditions. Note that when conditions are bad that is when you DON'T want to have to steer. You will get tired fast and will probably be busy doing other things.

[Alan Wheeler]

Yeah Pete, I love my haydraulic stearing. I just added a second station and it was a breeze. And yes I have plenty of feedback with the stearing. It is not as "isolating" from feel as you would think.
The only worry I sometimes have is just how much force am I exerting at certain times. Like the boat is backing out of the birth and the huge rudder is hard over, she takes some straightening up. I know an enormouse load is able to be easily applied. So I am careful in those situations.

[delmarrey]

See these two posts for more info..........................._/)

http://www.cruisersforum.com/forums/...aulic+steering

http://www.cruisersforum.com/forums/...aulic+steering

[CaptainK]

Hey Rick!!!

I was just reading about hydraulic rams for steering. And this one gentleman recommended "not" to mix componants. Like with new and old, from different manufactuers.

I am looking over blueprints for a 47 foot sailboat right now. And am having one hell of a field day with trying to figure out which manufactuer to want to buy for this upcoming project.

The one recommended by the designer, is no longer sold on the market. The blueprints called for a Wagner hydraulic ram. Model # 175-1000. They do not make this model anymore.

Guys!! Which hydraulic rams is the best one on the market par none? And which one has the best warranties?

[Alan Wheeler]

I was just reading about hydraulic rams for steering. And this one gentleman recommended "not" to mix componants. Like with new and old, from different manufactuers.

There's nothing wrong with mixing stuff K. You'll be fine. However, buying a compleate package, you know you will have everything you need and helm is matched to Ram. That is the important part. Having a Helm pump capacity matched to a Ram capacity. So you can get the best power ratio and correct Turns lock-lock. But even then, it isn't exact. There is a lot of fudge factor in the Turns part. Most manufacturers only have two or three helm pumps in their line up.
Wagner didn't make their own Ram. It was made by someone else for them. There is nothing special about the ram. Except that it will have non-corrosive metals of some form. The imortant thing is to make sure you have the correct size for the boat. A 47ft boat is going to have a ram with something like a 5/8"-3/4" shaft and probably an 1 3/4"-2" cylinder. The length is not critical as it can be fitted to suit. However if the blue prints give all the daimensions for the ram, then you could try tracking down a manufacturer that has that as a stock item. However, Rams can also be made to suit needs and should not cost any different to off the shelf.
I imagine the best Warranties are going to be with the most expensive makers. There is really nothing "special" with Rams. As long as it meets the required power specs, then little goes wrong with them. I would not worry to much about who has the best warranty.

[NoTies]

And make sure you get a "balanced ram". This ensures that you get the same effort/turns lock to lock.

[delmarrey]

A lot of the new pumps are variable which can increase or decrease the flow rate. The balanced cyl. on my 40 footer is a 1-1/2" bore w/ 10" stroke running a spade rudder. Depending on how your rudder is hung is what with determined the sizes you need. But the flow rates have to match the cyl capacity.

I'm also running a 54" helm wheel which makes mine very EZ to steer. I just spin the wheel to turn or steer with two fingers.............._/)

[Rick]

Check out Hynautics and Kobelt rams. Wheels and pwederel make good points to watch out for. It is simple math to calculate just how many turns a helm pump or how much time an autopilot pump will take to force a ram displacement from one extreme to another from their given specs.

Whatever ram you get immediately buy spare seals and spanner for removing the keepers, or whatever, put them in a zip-lock bag with a hole in it and tie wrap the bag to something near or on the ram so that it will always be available years later when you might need to replace them at your convenience. Such seals, once you identify them, are normally readily available from any bearing supply house using the identifying numbers stamped on them. If you buy spares from Hynautics, for example (easy and inexpensive to get) write down the numbers from the parts themselves for later identification and ordering from anywhere.

If you shop for a helm pump(s) it is a great advantage to get one with a variable ratio setting, either by a screw or even adjustable from outside at the helm. There is no rational engineering reason why you cannot mix brands as long as you observe the parameters such as operating pressure, required relief pressure, and any limitations of the helm or autopilot pumps regarding applied filling reservoir pressure tolerated. With Wagner and Teleflex pumps you can constantly apply a filler pressure from a pressured external tank whereas with a Kobelt pump the seals are not designed to operate with the fill pressure more than a few psi above ambient. Not a problem, though, because you can still purge the system with about 6 psi and then bleed off the pressure when done.

If you install an autopilot pump with integral relief valves then you will not have to buy discrete ones for your system (in case something hits the rudder the relief valves give at say 450 to 500 psi to keep from damaging the rudder).

For offshore applications I prefer to go as large as economically realistic on the ram shaft diameter which for a boat your size is probably about 1/2 inch. The larger the cylinder diameter the larger is the required helm pump capacity and autopilot pump capacity so you can see that there is definitely a limit to the ram volume that is affordable for the whole system, regardless of brands.

[CaptainK]

Well guys.

I will be freakin' honest with ya all.

I know nothing. I 'mean" nothing!! About hydraulic steering rams.

All I read was that this one man recommended "not to mix those things up. Cause he had trouble with that problem.

I looked the blueprints over. I could not make heads or tails out of it. It does not mention anything. Except that model number that I mentioned on my last post.

I am beginning to start to see where this future project is starting to lead me too? Into through a lot of *ull$hit!!

I am going through a lot right now. And I was trying to figure this stuff all out. I pretty much have everything else down packed. But not the steering ram. Cause this is a center cockpit sailboat.

Personally, I am not a fan of these type of sailboats. I am a aft steering sailboat fan. But the original blueprints call for this boat to be a center cockpit boat. And the blueprints are drawn up for a center cockpit, two masted boat.

I have no knowledge of rams what-so-ever. And the internet has vague articles on them. My time on the computer now days is less than it used to be. And I have no "real" time to go searching through 1,000's of web entries anymore.

So if you guys know any manufactuer. Which marine equipment store in the USA which sales these items. For a sailboat of 47 feet long. Which is balanced. And mounted to a beam on the back aft end of the boat above the rudder. I could sure make use of the weblinks if you have them.

That is all I can say about that. Like I said. I know nothing about these things. My knowledge is extremely limited on these devices.

Kevin

[CaptainK]

Oh yeah!!

I forgot to mention these things in my last post.

I got this incredible offer for a 47 foot long monohull hull. For "free"!!

The man who built this hull bought the blue prints 36 years ago. From marine designer Bruce Bingham. And during the years. He only got to build only up to the hull. The hull is complete.

He developed symptoms from exposure to asbestos. From his years working in the ship yards. And he had to stop building on her.

He offered to sale. No one bought her. He then resorted to giving her away. So far no one came to get her. And then I came along. Thanks to my friend Jesse out in California. And he put the word in for me.

I called the man up. And told him that I was interested in the hull. And he said it's all yours!!

I already had the blueprints for over two years now. Cause the same man said that I could have them. But now. I could have both. And building this boat will be a lot of work. I do have photos of this boat hull. i will try and get them scanned some time within the week.

Kevin

[CaptainK]

Rick.

I just found out while searching the web. The brand names of the hydraulic rams that you recommended.

I found the Kobelt website. And downloaded the Adobe files. No problem there. I wonder if the model 7040 or maybe the next model up would be enough? The blueprint only calls for one hydraulic ram.

It's no wonder I had a hard time with the Hynautic brand. That company has been bought out by a company called Teleflex.

Here's the weblink on where I found out about that bit of news.

Hynautic Marine Steering

Rick. Thank you so far for those brand names. Now all I have to do. Is narrow down to which kind of ram pump I do really need? Balanced or Non-balanced?

Kevin

[delmarrey]

Kolbelt is what I installed in my boat just last spring. Here's some pictures........................_/)











.................................................. ....._/)

[Alan Wheeler]

Del, I think I said it before, but I will say it again. That is one bloody fine installation. I see I have a new bar to reach.

[Alan Wheeler]

K, you don't have to sweat this at all. It's what the manufacturer is good at. All you need to do is Email them and say this is what boat I have, what do you recomend and they will do all the rest. They will tell you what you need and probably give you a quote as well. There is more to it than just the ram. You need brackets and fittings. So ask them to design and quote the whole package. Unless you can, or you have a mate that can engineer stuff for you.
Oh and be prepared. The stearing is one of your big ticket items. It won't be cheap. You are going to have several big ticket items that you can't scimp on. Stearing, engine/propulsion, mast/rigging. All the rest you can buy second hand and get away with if budget is tight. Engine can be second hand, but you need to know what you are buying. Can't wait to see the photo's.