Rudder Stop Adjustment?

[natew]

So I'm fitting a new autopilot with a linear drive motor. From the looks of It I need to adjust my rudder stops. But where and how? Attached is some pictures I don't see any rudder stop do you?




Sent from my iPhone using Cruisers Sailing Forum

[barnakiel]

Possibly the fin (foil, blade) has stops?

Possibly the shaft has a groove and a stop?

b.

[Blue Stocking]

What limits you hard-over travel now ? Depending on the length of cable between the quadrant and the turning sheave, you can put stops on the cables.

[natew]

No idea what limits my stopping now.. Maybe there are stops on the cable already i'm just not sure what i'm looking for or how I would adjust it?

[Blue Stocking]

If you can see that the quadrant does not come up against any physical or mechanical stops, then it may stop when the chain to cable transition reaches its limits inside the pedestal. Or there may be stops along the cables frfom pedestal to turning blocks. Some more info is needed here.

[model 10]

If there is something in the steering pedestal stopping the rudder I think it would have failed before now. This is not the right place to stop rudder travel. The forces on the internal parts would be quite large due to the gear ratios etc., The stops needs to be at the quadrant or at the rudder.
Of course if the boat has never backed down and had the rudder go hard over you might never know.

[natew]

Originally Posted by Guy

If there is something in the steering pedestal stopping the rudder I think it would have failed before now. This is not the right place to stop rudder travel. The forces on the internal parts would be quite large due to the gear ratios etc., The stops needs to be at the quadrant or at the rudder.
Of course if the boat has never backed down and had the rudder go hard over you might never know.

In my sailing time with this boat i've done two accidental 180's due to wind and sea conditions and the old crappy autopilot (wheel pilot)... Would say that both times the rudder was hard over one direction or the other so the stops must be sufficient for the jobs wherever and whatever they are. Going to try and get some more pictures of the steering and linkage. Maybe someone will see something?

[natew]

A couple more pics maybe something will look familiar to someone.


Sent from my iPhone using Cruisers Sailing Forum

[model 10]

That does not look like cable steering at all. What pushes and pulls on that big control arm? That must have some sort of adjustment on the ends. That would be your rudder travel adj?

[natew]

No idea.. I guess I can follow it back further towards the wheel.. But basically if you look at the first picture that thing with the huge rod is what connects up to the steering wheel and far as I know and have taken notice it is nothing more than a big beefy 1" thick cable of some type.

[Roy M]

Wow, that's an old Morse cable single cable unit. I don't think they are available any more. I used to have one, for twenty-five years, then had to switch to an Edson system because i couldn't get the cable. I had to change out the pedestal, as well, since it was a Don Allen, made for the single Morse cable and, likewise, no longer made or parts available. Which is all right by me, as the Edson is a dream, and I use Amsteel Blue cable instead of stainless.

Nate, I just realized you are sailing a Tristar. That would be consistent with the Morse cable system. You can build a pair of heavy timber stops to limit the tiller arm in its swing. This is a good idea because you, otherwise, have zero limits on the rudder. That can cause stalls and other awkward things, especially if you are surfing down the face of a Pacific roller. Anything that is anchored to something structural on the boat, and prevents the tiller arm from rotating more than 35 degrees on either side of the centerline. Your autopilot will be much happier and do nice things for you in appreciation.

[Dsanduril]

What Roy said - +1

You're current stops are the Morse cable itself. Going one way, when the knuckle on the end of the cable gets pulled up against the sleeve you can't travel any further. Going the other direction, the same thing, with the knuckle at the wheel end being the stop. That relies on the Morse cable being well secured, and stiff enough to handle all loads. Better to install a couple of solid stops and not rely on the Morse cable getting to the end of its travel as a stop. On the other hand, its probably been working just fine that way for a long time.

[natew]

Any excuse to get out the power tools.. and well the epoxy.

On the rudder stop issue, it looks like I may be ok as is. I picked up a angle measuring tool at harbor freight (could be off a couple degrees) and first measured my rudder travel in each direction, comes out to +/- 20 degrees which seems rather shallow but i've been quite happy with my turning ability but maybe I should be adjusting that a little? I also turned the wheel hard over each direction until it stopped and popped the pin on the AP drive unit and found that I couldn't turn the wheel any further so it's definitely being limited by the cable.

Hm.. 20 degrees? Adjust for more? Leave as is? Will definitely take up the advise of installing some blocks to stop the tiller lever when I get this figured out.

[Dsanduril]

There really isn't much you can do to adjust the stop angle. The travel of the Morse cable is fixed by the length of the inner (push/pull) rod compared with the length of the outer sleeve. That's all the travel you get (+/- a little bit with the adjusting screws/threads at both ends). So, really the only way to adjust is to move the cable connection a little further in (more angle) or out (less angle) on the tiller arm. But that will change the steering effort. If you're happy with the way the boat handles I'd leave it alone, but possibly add some backup stops tied to the structure. A following sea that grabs the rudder can exert a tremendous amount of force...

All you want is something for the tiller arm to run in to before you've gone too far. If there's no good point right adjacent another option is to put in cable stops that are connected to the framing at a strong point and to the tiller. I'd use Amsteel or similar, a couple of feet long, one from each side. These can be a pain with flexible cable steering, but with the push-pull you have in the Morse and the AP they don't get in the way. Too far one direction and the stop rope/cable will go tight, to far the other way and the other one will take up. No epoxy required

[natew]

Wait.. Hold the train Dsanduril.. You're a genius! Actually I HAVE two cable stops. They are dangling off each side of the hull.. Never could figure out what they were, assumed maybe they were some type of straps for a fuel tank that was no longer there.. But infact there are even two holes in the tiller piece which I would guess fit exactly those cables Hmm.. Off to investigate further.