Mahe 36: Rudders - Steering

[boden36]

Have you tried disconnecting of all the linkages and just working the rudder backwards and forwards by hand for some time in the hope that it will loosen up?
Regards, Richard.

[markpierce]

Sorry. I haven't figure this out yet.

[cat man do]

Originally Posted by Dragon Lady

Yeah, I would be nice if the FP ones were that simple. They would probably work a lot better too.

That they would, why overcomplicate something so simple

With all due respect I don't know how good you are at reading engineering drawings,

Trade background in boat building on vessels up to 120ft in size.
I think I can manage

especially French ones

May have been an issue if they were in french, but they are not

,

but if you look at what Cotemar posted you will see it's quite a different set up to what you have.

That it is
But easily remedied into a set-up that is more conventional ( fiberglass tube glassed into hull with supporting structure) and more secure if there is ever an impact IMHO

[vayacondios]

Richard (Boden36)
Yes have tried loosening the rudders up. Hubby thinks that moving them back and forth, and spraying WD40 is loosening them up. They are still very hard though to move.
Rozzie

[mrm]

Just a few (Euro)cents to this.

From an engineer perspective it appears, that those bearings have a fundamental design flaw. The bearing case, which at the same time is an outer race is made from Aluminium (or one of its alloys). The bearings are not water tight, and operate in a corrosive (salt) and abrasive (water suspended particulate matter) environment. The combined effect will destroy any anodising protection layer manufacturer might have designed and will lead to Aluminium Oxide forming. Now, it is important to observe, that the volume of Aluminium Oxide is many times greater than the volume of metal it replaces, so a lot of pressure will build between inner and outer races and the bearing will eventually seize.

@Dragon Lady & cat man do: if you do material stress analysis you will notice, that a pure sleeve bearing will create a stress point where rudder stock enters the lower bearing. This is OK but, for a given load, requires a bigger rudder stock diameter. In a world of cutting costs and weight, thinner stocks are used with provisions to allow for some bending and stress distribution. JP bearings are designed to do just that. If only they used a better material for the bearing case/outer race..

Marius

[Laidback]

Originally Posted by vayacondios

Richard (Boden36)
Yes have tried loosening the rudders up. Hubby thinks that moving them back and forth, and spraying WD40 is loosening them up. They are still very hard though to move.
Rozzie

Interesting ! how does one spray a bearing that is under water with WD 40.
With some material the gasoline component in WD 40 will itself cause swelling and binding

[lancelot9898]

I haven't read every post on this thread, but I'll just state what happened to me quite a few years ago when I had rudder problems. I have wheel steering with cables running from the pedestal to the quadrant below deck. Out for a day sail, the wheel becomes very difficult to turn. I get the emergency tiller out and use that to steer, but it too is very difficult to move the rudder. Back at dock I think that there is a problem with the rudder shaft and associated bearings/bushings causing too much friction however I look at the cable system and think there just may be a different cause. Even when I put the emergency tiller on the rudder the cable system was not disconnected from the wheel so in effect that cable system was also contributing to the friction that the rudder had to overcome. There was no jamming of the cables and the pulleys all were fine so that was ruled out, however there was one more friction point and that was where the wheel shaft terminated into the pedestal. There was no grease fitting there, but it was easy to install one and that could elimated another source of friction before going to the rudder shaft itself. Once the greese fitting was installed and a shot of grease inserted......the wheel turned freely and has been good for the past 15 years! ....even without annual maintenance ...although thinking about it maybe I'll give it another shot of greese next week

[Edmund]

Last evening, as we entered our harbour, I suddenly needed to adjust course. I jumped to the wheel and tried to turn it for a sec before I remembered to take it out of Auto, and suddenly it felt very light. I felt there was no big power used, but the picture shows what had happened...

I'll fix it myself, the bother of trying to get it fixed under warranty ain't worth the effort. But this is obviously a week point, and the design is not good. The distance from the steering mounting plate to the carrying wooden plate is quite big (through the two white distance plates used), creating a large momentum from the force used on the steering wheel. Combine this distance with the relatively small area of wood who is to resist this momentum, it does not take much load to break it, especially when turning starboard.

[Cotemar]

Edmund,

I had a similar event happen to me last year as I was pulling into a cove.
Did not realize I still had the autopilot on and as I stopped, the boat turned and of coarse the autopilot turned hard over. I actually thought I snagged a lobster pot.
I grabbed the wheel and held it for a second and then the wheel went slack.
Turns out that I popped the autopilot fuse.

I am surprised that it did not do the same for you.

Seeing your picture, I may bond another board underneath to strengthen it up.

Mark

[Dragon Lady]

That's a big problem, FP should really inform the Mahe owners of this issue.
Before it becomes an even bigger problem and the lawyers get involved.

[Cotemar]

Dragon Lady,

Actually, Its not a big problem. It only happened to Edmund. My fuse blew when I did the same thing, so I would have expected Edmunds autopilot fuse to blow also.
This is the first one like this that we have seen.

I can tell you first hand. Always shut off the autopilot when approaching a harbor and hand steer your way in.

Mark

[Dragon Lady]

Mark, it will be a big problem if some gets injured or killed because if the issue.
The fact that the Teleflex cable mounting can break off, even if operator error is the cause is a major concern.
If the system was designed correctly, manual override of the AP would cause it to disconnect not blow a fuse.
Any way structural failure of the steering system is a rather shoddy back up to the fuse.
What happens when someone installs the wrong amp fuse?
If this sort of thing happened to an aircraft all similar models would be grounded worldwide until the issue was resolved.
Don't trivialize this just because it has only been reported once.

[cat man do]

Originally Posted by Cotemar

Seeing your picture, I may bond another board underneath to strengthen it up.

Mark

And a supporting web

[vayacondios]

Update: We met with the FP Broker here in Aus (Multihull Solutions) last week and they really stepped up to the plate, even though we are just out of warranty. They are ordering bearings, and we will then get hauled out and have an engineer look at exactly what the issue is. MHS is paying for the haulout and fix. That's really exceptional to get some support with this issue. Will post findings and outcome asap.
Rozzie

[nigel1]

Hi Rozzie,

Thats really good news, hats off to FP Broker, nice to see good customer service.