Rudder Pin design

not on mine the tip of the rudder rests on the back of the yak and there doesn't seem to be much pressure once the cord is over it

Hi Bob

Thats very interesting. Long ago I gave up on the plastic pins and had a steel one made up that one bust the rudder housing then I had a brass one made up, it was so tight in the gudgeon ring, I had to sand it a bit with wet and dry the until the fit was perfect...just slid down in there a treat. I dont sail in 30 knots of wind in the AI, probably more like 10-15 but I do sail lots and for the last year I have had no problems whatsoever.
Now I have received a new hull and am about to transfer the pin. I looked at your photo of the inside of the hull and checked my old hull, it appears to be a lot more solid around the column than yours, then i had a look at the new one and it LOOKS same as yours. This maybe just a manufacturing anomoly on the old hull. I would be very careful about putting in my old brass pin into the new hull without first ensuring that I beefed up the inside of the transom but I dont know what to use as a fill, no molten plastic available here!
http://i224.photobucket.com/albums/dd14 ... ldhull.jpg
http://i224.photobucket.com/albums/dd14 ... ewhull.jpg

That's quite a difference. Mine, an 08, sort of looks like the early one on the left, and your new one on the right, a sort of half and half. It sounds like the amount of plastic in that area varies.

Pirate... I have already told you that "We hear you".

Please give us some time to work through the issues. Please have a bit of trust in us here.

No I had not seen the photo of the worn pin you posted, but I have heard many a concern coming from you yet no failed pin report, so if you are simply concerned... contact your dealer anyway and request a replacement. Give them the worn pin for our inspection. Steve explained (in this thread) what he needs in Australia as far as a warranty claim.

As I explained a few times already... we need to confirm that the pins are of the correct material and strength before we get to excited about making big changes.

In the mean time... I suggest taking it easy on the down control line. Only cleat with enough tension to keep the rudder down. This is the most likely source of excess loads on the pins in my opinion.

_________________
Matt Miller
Former - Director of Parts and Accessory Sales
Warranty and Technical Support
Hobie Cat USA
(Retired 11/7/2022)

I hear you Matt and I am appreciative Hobie are taking this seriously. Hobie does appear to be a very customer supportive company and I am sure you would replace the pin without qualm, but that is not what I was trying to achieve here. Again thank you.....Pirate

Matt,

Could you, or some other knowledgable person explain the proper method of getting the rudder down, and bringing it back up using the recent pull line placed to the starboard side of the cockpit.
I have been pulling the down line with quite a bit of force and jamming the line in the cleat whilst under this high tension in the belief that this is what I'm supposed to do.
In this thread I've read that the rudder doesn't even need to be cleated once it's down. Is this correct?
A full explaination on how to employ & put away the rudder would be much appreciated as I have never had any instruction on this, and am probably making the wrong assumptions.

Thanks,

Ger.

Ger,

More often then not, I don't cleat the rudder down - in fact the way I see it is that there is no need to do so unless you find you are in such heavy weather conditions that you need to do so to maintain some rudder control of the AI - in other words, when the rudder has popped up unexpectedly or similar. I have been in some pretty rough stuff but can't remember a time when this happened.
I guess some of the oldtimers will have a few things to say about this
Mickey

1. I generally don't cleat the rudder. It seldom pops up.
2. Yes, you could wind up with a cracked hull.
3. Yes, on the day my wife broke two pins, there was a lot of very confused chop. It was large enough to swing our boats about a fair amount, maybe as much as 15-20 degrees. The boats can kind of pivot if on top of a bit of steep chop with bow and stern more or less clear of the water. One of my theories is that she was trying harder to correct for those swings, while I just let it happen and let the boat regain control of itself. Another of my theories is that even if she did not do that, her rudder may have come down into the water going sideways pretty fast. Yet another theory is that she was trying to turn the rudder during one of these sideways entries, and the hinge bound up and the pins got twisted off.

Ron,

I do not believe that she hit something without seeing or feeling it, then went right back out and hit another object, again without seeing or feeling it.

Bob, had you and your friend been sailing with the rudder locked or cleated down when this happened?

_________________

The down / up lines work easily enough, so the question is how hard to pull on the down line and do you cleat it?

The reason for the cleat is that the standard hold down doesn't hold the rudder down well enough when at speed. The cleat is provided as a lock. The amount of tension required is variable to the conditions / speed you attain. If the rudder is popping up while sailing at speed. Use a bit more tension on the down line and cleat.

There isn't a better description that I can think of.

We do have a small plunger system we have been working on that holds the rudder down in slower moving conditions. This is in some rudder systems already, but is not necessary due to the presence of the cleat as a lock.

_________________
Matt Miller
Former - Director of Parts and Accessory Sales
Warranty and Technical Support
Hobie Cat USA
(Retired 11/7/2022)

I cleat my rudder down hard--always. The one time I forgot, as I was pedaling out of a protected marina, I hit the light (7-10 mph winds) and the rudder came up enough that it could not control the boat--quite embarrassing since there were powerboaters coming in. It took me a while to figure what was happening.

Now, I have never broken a pin (knock on wood, or should that be plastic). Is there some connection between rudders that come up easily if not cleated and not breaking a pin? Just wondering. Some people, I believe Tom Ray, say they never cleat their rudder--I could not do that.

Keith

_________________
2015 AI 2, 2014 Tandem

"Any intelligent fool can make things bigger and more complex ... It takes a touch of genius and a lot of courage to move in the opposite direction." A. Einstein

"Less is more" Anon

I can sail my boat uncleated every time and there appears no tendancy for the rudder blade to pivot up. My sailing experience though tells me that if it were to pivot in moderate conditions there would be quite additional stress on the rudder gudgeon system if I was attempting to resist weather helm.

What grabs my interest is that I have encountered a feeling of a binding of the steering system whilst sailing downwind in lighter conditions a couple of times and after speaking with Mickey on the subject he has felt the same. I am still firmly of the belief that the pin holes in the rudder box and boat are unequal in diameter and oversize compared with the diameter of the pin causing it to distort and bend leading to eventual twisting of the bottom end of the pin competely off.


See Astros pin for a good example of this destructive force in action.....Pirate

I had a look at the setup with the lines Tom and it is most ingenious - there are actually two bungees - one is inline with the spectra line and the other is parallel and attaches the handle of the downline to the hull. So, when the handle bungee is fully stretched, the inline bungee is only partially stretched. This means that even with the downline out as far as it will go, it is still fairly easy to pop the rudder up. It also means that it is impossible to lock the rudder down tight by cleating the downline.

So, I agree, there is no point in adding yet another bungee to the system.

_________________

From the photos of the 'twisted' rudder pins. It appears that the pin is
not rotating when it should and the torque applied then causes the pin
shaft to twist on itself.

For the first fix...has anyone tried to 'lubricate' the rudder pin before it is
inserted? I use 'Boeshield' lube on my Mirage drive. I was told that
it has some kind of wax-film which is left behind as the liquid evaporates.
I am wondering, with the 'loose tolerances' some people have in their
rudder pin assembly, would the Boeshield film help keep the rudder pin
from binding and twisting?

For the AI rudder assembly, the pin was obviously designed to be the 'weak link' to protect the assembly from major structural damage.
Looking at the assembly, it appears that Hobie was worried that if the rudder were struck, that the rudder would want to swing upward and the pin was designed to break (snap) first as the rudder swung safely away.

However, it appears that the 'weak link' is too weak if the pin stops rotating.

The 'broken' pins appear to first twist and then break. Something is causing the pins to first jam and then because of the formula of the plastic to break. Someone has already mentioned that the plastic pin
has two breaking tolerances. The first is the one planned and tested by Hobie and that is a perpendicular stress applied to the pin (snapping
the pin in two). The second, I am not sure Hobie has shop tested...
that is the amount of torque (back-and-forth twisting) the pin can tolerated before it shatters.
In aircraft wings, the metal hardly ever snaps with one big flexure! Usually, repeated small amounts of flexure slowly causes fatigue and slowly micro cracks appear and spread until the structure fails.
It certainly seems to be the case for the rudder pins!

I think that if Hobie were to manufacture a slightly larger diameter rudder pin to remove the 'slack', that it probably won't solve the problem. The plastic in the pin will jam in the sleeve and still twist to destruction.

On my larger sloop, there is a brass sleeve in the rudder shaft mount.
Brass usually doesn't bind against other metal parts. In effect, it
is 'self-lubricating'.

For a second fix...in my shop, we have several pieces of equipment which
have both plastic sheets and pins which have a lubricant in the plastic itself which makes the pins self lubricating.

So I am wondering if Hobie might want to have a few pins made up of similar plastic and field test them. It appears that Hobie chose a specific plastic formula and has kept with it.

I think that substituting a different plastic for the pin might be a better
solution than Hobie having to retrofit a new rudder assembly design
to the many AIs out there. As the number of new AIs increases, it
is going to become much more expensive to Hobie if they finally decide
they have to do some re-engineering

I have been lubricating mine with SailKote since my wife broke two pins. Maybe it has helped. No more pins have broken. Of course, lots of people have sailed for more hours with no lube, so maybe it's not doing anything. I figured it couldn't hurt.

Boeshield is great against corrosion, being originally designed to fog the insides of wings and such. I chose SailKote because it's a dry lube, attracts less dirt, and I'm not worried about my pin corroding.