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 Post subject: rudder kicking up
PostPosted: Sun Oct 14, 2007 3:32 am 
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Location: Phuket, Thailand
Thanks, gentlemen for the help with my rudder pin!! the polypropylene rod works just fine and I was able to get it past the rudderlines without problems thanks to Yakaholics tip.

So, I went out in about 6-8 knots of wind today and the new rudder worked fine on both tacks.....for the first 45 minutes....until it popped free of the lock down screw whilst i was tacking and from then on it popped up every time the wind picked up or when ever I hit a bit of chop, so I am back to square one.

I remember someone else writing about the same problem, the rudder is twisting free of the open side of the bracket. I will increase the drum tension and see if that helps but Ive an awful feeling this isnt going to help. i read of you all going out in 20 knots of wind and having a ball anything more than 10 and I'm going round in circles rudderless.

Philip


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 Post subject:
PostPosted: Sun Oct 14, 2007 4:46 am 
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Location: Virginia Beach, Va.
Philip this juryrig has been working well for me so far.
http://kfs.infopop.cc/eve/forums/a/tpc/ ... 4481068934

Did you unscrew the lock down so that the rudder could reseat after it popped out? The reason I use the top bunj to lock down my rudder is because I blew out my lock down hole.
gwiz


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 Post subject:
PostPosted: Sun Oct 14, 2007 6:07 am 
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Location: Central Coast NSW Australia
I don't have an AI but I have just completed fitting a twist-n-stow assembly to my older tandem with the pull up rudder. I was able to run extra control lines (2mm spectra) alongside the existing lines inside the hull giving me control from the cockpit.
Image
I have them exiting through a cleat which I use to lock the older pull up assembly down.
I'm wondering if you may be able to do something similar to lock your rudder down from the cockpit when needed? Maybe something like this:
Image

You may be able to work out a way to attach the line end to the rudder that keeps tension on it and still allows it to turn.


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 Post subject:
PostPosted: Sun Oct 14, 2007 8:17 am 
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Location: Phuket, Thailand
gwiz wrote:
Philip this juryrig has been working well for me so far.
http://kfs.infopop.cc/eve/forums/a/tpc/ ... 4481068934

Did you unscrew the lock down so that the rudder could reseat after it popped out? The reason I use the top bunj to lock down my rudder is because I blew out my lock down hole.
gwiz


Hi Gwiz

Yes I did, but the problem is exactly the one you mentioned in a previous post some months ago...

"The reason is that on the starboard tack the rudder is held tight to the mount. On a port tact it can flex and come off the lock down bolt."

Thats just whats happening.

Actually I bOUGHT a replacement 'balanced' rudder whilst waiting for my warranty replacement and I'm using that one now so if I will drill a hole in it and attach it to the bungie hook as you suggested.

One thing of interest is the distance from the end of your rudder pin theres quite a gap where it exits thru base of the mount to the rebated part of the rudder. If I lock down my rudder the pin is JUST touching it, maybe this is contributing to the problem.


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 Post subject:
PostPosted: Sun Oct 14, 2007 9:03 am 
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Location: Virginia Beach, Va.
Philip
Mine looks like that because I sheared off the bottom of my pin and had to screw a little stainless screw up into the rudder pin remains.

I blew out the bottom of my lock-down hole and now use a bungee ball clip instead of a bolt but it forces its way under the rudder assembly on top so a screw prevents that as well. It won't shear however should I run it aground but the bungee cords will flex.

gwiz


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 Post subject:
PostPosted: Sun Oct 14, 2007 7:02 pm 
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Joined: Sat Nov 12, 2005 10:46 pm
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Location: Escondido
Stringy, your Twist N Stow update looks really neat! You might want to consider posting a "How To" on the general forum because there may be some who would like to upgrade to the sailing rudder! 8)


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 Post subject:
PostPosted: Sun Oct 14, 2007 7:18 pm 
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Location: Central Coast NSW Australia
Thanks for the comment RR. Yes I will post as soon as I take a couple more pictures. I was thinking that the problem of the AI rudder kicking up may be solved by running another control line to lock it in more positively. I was surprised how easy it was to fit another line alongside the existing lines.


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 Post subject:
PostPosted: Sun Oct 14, 2007 8:01 pm 
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Location: Phuket, Thailand
Hi Stringy,

A belated thank you, system looks good and a more detailed posting of 'how to do' would be greatly appreciated.

Philip


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 Post subject:
PostPosted: Mon Oct 15, 2007 3:42 am 
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Location: Phuket, Thailand
Hi Gwiz,

With a bungee tied to the base of your rudder, the rudder will lift out partially when you hit a stronger gust..correct? I mean bungee's bungee-it stretches. With the rudder half cocked the tension will increase on the steering lines, it must be quite a job holding on!!!. I just remember my Hobie days when the cams wouldnt stay locked, that was easily solved you just increased the cam tension.

has anyone tried G clamping the the lockdown nut onto the rudder?


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 Post subject:
PostPosted: Mon Oct 15, 2007 5:13 am 
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Location: Virginia Beach, Va.
has anyone tried G clamping the the lockdown nut onto the rudder?

Philip I am not sure exactly what you are asking, you probably could find a clamp of some sort which would clamp the 2 parts together.

I blew out the lock down by drilling the hole all the way through and using a metal bolt with a nut. It locked it tight and provided the best control until it broke.

I decided to go with bungee cords because it seemed like I just kept chasing the problem to the next weakest part. The bungees hold it but allow movement when the tension becomes great enough to break plastic.

The bungee running through the rudder does make it a little harder to operate the lever but its added tension keeps the rudder in place and the yak on course.
gwiz


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 Post subject:
PostPosted: Mon Oct 15, 2007 6:18 am 
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Location: Phuket, Thailand
I had a good long look at the assembly this afternoon, I am not an engineer but seems to me like there's no way your going to keep the rudder down when the lock screw is so far away from the max area of stress which is way down below the waterline, the leverage is going to be so great..its bound to pop. then I looked at your rudder, this is the upgraded balanced rudder, yet, still you have done everything you can to keep it down, you have put wings on it, drilled a hole thru it and secured it with a stainless bolt till the hole blew..now your obliged to sail with a bungee cord thru the rudder and as you said one always goes to the next weak point which is probably going to be steering cable and handle. Whats worse is that I am probably going to go the same route.

I love to kayak (I have a perception Sea Lion, unlike the AI its weakest link is ME) I've owned two Hobies and windsurfing is a passion, so I have been caught out plenty often due to my own incompetence... one hopes one learns.

When my rudder popped up I was sailing upwind towards a darkening horizon, so it was OK, I just ran downwind for home...no loading on the rudder. I beached well before the line squall hit. A line squall in the tropics is a short lived but nasty event.

We have a second AI on island, the owner is a good guy but with little sailing experience....had the wind been behind him and the rudder failed he would have faced an upwwind leg into the teeth of this thing, if he had been on mine the first gust would have popped the rudder and he would probably have rounded up beam ends to the wind. I am wary these days to talk of wind speed but here when a line squall aproaches thers nothing ahead other than a rash of whitecaps, the wind inside is particularly vicious.

So tommorow I will tighten the drum tension and when the rudder pops I will clamp the locking nut to the rudder and hope not to hit a snag, when the next decent breeze kicks in I can see the clamp flying off then I will move to the bungees. next will come an increase in the tension on the rudder steering lines plus the drag of the bungees in the water. What a sad indictment on the original design.


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 Post subject:
PostPosted: Mon Oct 15, 2007 9:10 am 
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Joined: Fri Mar 23, 2007 8:12 am
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Location: Florida
Philip.

Take care not to over tighten the rudder steering lines. They may cause premature failure of your rudder pin. I had tightenen mine up and they stretched the nylon pin.

I had a rudder sheer off from the T&S also and I wasn't even out in that much wind, maybe 15mph with some intracoastal chop.

I now have 7 bolts holding on my rudder to the T&S and have added a small stainless steel flat metal brace using 2 of those bolts. The brace has 2 extra holes for adding bungie which I have not had to use yet.

Will get soms pics eventually.

Image

All 6 bolts and nuts are installed as normal with the rear most 2 bolts .75" longer and have the standard nuts below the brace. The brace is from hardware store (door hardware) and fits the 2 holes w/o drilling. 2 more SS nuts added to hold brace in place.

The 7th bolt goes thu the diagonal section of the rudder & T&S - it is the phillips screw head seen in the middle.

My rudder blade will now not likely ever shear from the T&S. Rudder has less ability to twist or warp at speed. Plus the hole in bracket is left there for bungie if needed.

Looks ugly but does not stop normal up/down use of the rudder. Bracket is above the water line (mostly) - so as not to add drag.


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 Post subject:
PostPosted: Mon Oct 15, 2007 10:58 pm 
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Location: Phuket, Thailand
[quote="Yakaholic"]Philip.

Take care not to over tighten the rudder steering lines.

Thanks for the tip actually its not the rudder steering lines I want to tighten, its the drum, its a bit TOO easy to drop the rudder at present, I read a little resistance is no bad thing and should go at least part way to alleviating the rudder kick up problem.

Though I have not yet tried it, I'm worried the bungee idea will only exacerbate the problem by allowing the rudder to partialy lift up out of the water when the wind picks up and put a load on my steering lines that they are not designed to take. Lot of ex Hobie sailers on the forum probably experienced this when launching thru onshore winds, couldn't lock the rudders down in the shallows, had to get out thru the mush into deeper water first...remember how the tiller felt close hauled with those rudders trailing behind half cocked??? Pretty heavy!!! Thats whats going to happen when the bungee stretches. Just try snapping the rudder off its lock down pin in the shallows or on a tressle...it takes quite a force to snap it free, yet those forces are acting on that rudder in about 10 knots of wind, thats about the wind speed the rudders going to start pulling against the bungee on my boat.

I had a rudder sheer off from the T&S also and I wasn't even out in that much wind, maybe 15mph with some intracoastal chop.

Well maybe the rudders too flexible and this is always going to be a problem. Make the rudders out of a less flexible material (carbon, and slap it on the bill!) and WHY have a rudder that automatically kicks up anyway??? seems like when you want it to kick out of the water it doesnt and the rudder pin gets busted and when you need it to stay down it wont!!!!! :? Windsurf fins are fixed, we do bust them but not often. Why not a gudgeon ring lower down the transom a bracket on the rudder and a second nylon rudder pin through both. you would have to remove the pin when you came in but then, if its deployed, you already have to unscrew the lock down screw. Not something we could do as theres no clearance between the rudder and the hull at this point but maybe an idea for future craft.

I now have 7 bolts holding on my rudder to the T&S and have added a small stainless steel flat metal brace using 2 of those bolts. The brace has 2 extra holes for adding bungie which I have not had to use yet.

Well the more holes you drill through the rudder and housing.........

Will get soms pics eventually.

Please, yak, some more pics and if you have time one of the bungee coming out of the steel plate.

For now I am going to try this afternoon with the most basic fix a 2" cast G clamp!!! Its bloomin' heavy and looks rather 'agricultural' but it will clamp the rudder to the housing, whether or not it will survive the rigours of the ocean for more than 2 minutes and not get washed off I have yet to see (somehow have my doubts its going top hang in there long!) Hey, if it does maybe on the merits of its weight alone it will keep the darned rudder down and Hobie can put it in their catalogue!!!!!!!

P

Image


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