SV "Follow Me Follow You" in difficulties in South Pacific

[Tranona]

I wonder about the use of these high teck materials for the huge spade rudders. Same also goes for the use of Aluminium stocks, as in Hanse yachts. The problems with Carbon composites, is that they don't bend or give warning of breakasge - if they are going to break, they break. Presumably they are much more prone to failing under a shock load as there is no give in the structure?

As for Aluminium, I think that this is asking for trouble, especially if marina based with stray currents. You won't know you have a problem, and there is an arguement for dropping the rudder out every year to inspect the area hidden inside the hull and bearings.

I would prefer an massively over engineered S/S stock.

.

You may care to read the MCIB report on the Hanse rudder that failed in the Irish Sea. Despite extensive testing of the rudder (it was recovered after the sinking) by a specialist firm they were unable to determine the cause of failure. The sinking was due to water ingress because the rudder dropped out, not because of damage to the hull but because it was not in an area separate from the rest of the hull.

The rudder was made by Jefa, a Danish company which is a major supplier to European boatbuilders and was designed to ABS standards. It was aluminium of an appropriate grade. Both aluminium and Stainless are commonly used in this application - the former being lighter and I guess cheaper. However, there is not a history of failure of either materials in spade rudders as is noted in the report. This faillure seems to be the only one that has been thouroughly investigated, perhaps because it resulted in a high profile rescue. As also noted in the report, aluminium stocks can suffer from corrosion where the stock goes into the tube, particularly if antifoul is applied in this area. There are frequent reports of build up of deposits and surface corrosion in this area on Bavaria rudders leading to stiff steering, but dropping the rudder and cleaning seems to resolve it. However, when I checked mine after 7 years - 9 months in the water each year it was clean.

As to composites. They do fail by shattering. However, although there have been cases of failure in racing boats it does not seem an issue in production boats such as some of the Firsts. Like many others here I am suspicious of GRP tubes as stocks, and if the number of failures reported by Hunter is true - then I think they should reconsider their policy!

Coming from a long keel attached rudder background I was sceptical about spade rudders, particularly as some of the early attempts at skeg hung and semi spade were poor. However over the last 20 years or so thousands of boats have used them in all sorts of environments without problems.

 

[@#$% boats]

also have a broken composite stock

Hi all.
my hunter 380 also has a broken glass stock. it sheared at the hull. Heres somethimng interesting, as the back of the boat comes down on a wave the water bubbles up through the emergency tiller slots. Nothing like quality manufacture eh? I wont be buying a replacement from the company that made it, That would be crazy. So I am builiding one with a S/S stock. Can anyone tell me what size tube they use and how they taper it to the top bearing and down the rudder? Id appreciate any help here. cheers

 

[sailinglegend420]

We spoke to a yard in La Coruna who were going to repair ours but we decided to have a new one built by Hunters approved manufacturer which was a big mistake!

To repair yours I imagine you would need to cut around the seam of the rudder and open up the two clam shells. Remove the foam from one of them and run a stainless steels shaft that is the diameter of the TOP bearing down into the rudder a weld shaped bracing struts across it which should be encassed in fibreglass to protect the s/s in case of any water ingress - and then glass this whole frame to one of the clam shells. Bring the two shells back together and glass over the seam and then fill with high density foam. The bottom 6" bearing - if you still have it - is held in place by epoxy, using the boat as a jig. You have to get the rudder hanging centrally about the post hole and mark its position. Then remove the rudder and add the bottom bearing and half fill with epoxy. Refit and secure in the pre-determined position and allow the epoxy to set. Check for smoth rotation before totally filling the bottom bearing with epoxy and cleaning up.

Our replacement rudder came with the bottom bearing 20 mm off centre so we had to go through this procedure and are still fighting the manufacturers for full compensation.

Some more info on when and were and how this happened would be appreciated as I am still fighting Hunter for some kind of redress. PM me if you want to.

 

[JohannaMaria]

Claiming on your insurance

We have a Hunter 420 passage and broke our rudder in Biscay going into La Corruna. Only an 11 mile tow but it has cost us a fortune as the insusrance company said there was "no insured event". Which means the rudder wasn't damaged. We hadn't hit anything, the sun was shining with a gentle F4 and suddenly it broke.The failure appears to be due to poor layup of the GRP stock - not a composite or kevlar in sight. I cut the stock into several segments and there are clear folds and air pockets, and strands of glass that haven't been wetted properly. We have two surveyors who say it is faulty workmanship, but Hunter just say it's down to "abuse". The Cat A design of the boat means you should be able to fall of a 6 meter wave with no problems.

We have sent them sections of the stock which they said they would "burn test", but they have not done that. They are returning the bits to us, but it will cost about £700 to get the test done to prove that they layup is at fault. Is it worth it? We are still fighting them for some compensation, but they fall back on the "no warrantee" on rudders and keels clause.
I enclose a cross section of part of the stock showing the "voids". This was at least 8" from the part where the rudder broke - right at the narrowest part at the upper bearing.

Hi,
Re your insurers comments. Check whether you have latent Defect cover specified within the policy and if you do - pursue that line to support your claim. Worked for me with an electrical fire which the insurers claimed was not a an insured risk as there were no flames (!) Once they accepted that I could not of know about a defect and had not been negligent they 'coughed-up'. Worth a try?

 

[@#$% boats]

our friends at hunter

Hi sailing legend. I contacted hunter for a replacement, they sent me to their manufacturer. As i am in the middle of nowhere and the price quoted was laughable I asked for the stock size from both of them. I got no joy from either. Hunter has ignored me completely. I contacted the broker that sold me the boat and they asked hunter to help me with the rudder stock specs. They told me Don Martin from hunter will be contacting shortly. that was last week. No sign of him.
Amazingly some friends on a 30 year old Shannon rang Shannon to ask them to help me. They couldnt be more helpful and have offered to buy a rudder for me from hunter and send it over at their trade price cost. They also offered to make me one. Talk about customer service!! Something to be said for buying a boat based on the manufacturer not the boat.

My rudder sheared from a very light tap. I was surprised to see it floating away as I hadnt hit anything hard enough to break a normal rudder. The stock is very obviously flawed and hunter is crazy for continuing to use the same manufacturer.

 

[KellysEye]

>The Cat A design of the boat means you should be able to fall of a 6 meter wave with no problems.

The problem is the category system was hijacked by the (mainly French) AWB high volume manufacturers. It doesn't matter how lightly (or occasionally badly) something is built their getting Cat 1 is assured.

For what it's worth the American perspective on Hunters is they call them 'lake boats'. When you tell them they are Cat 1 in Europe they don't believe you.

 

[Bav34]

I don't really follow your logic when you say that you were ''staggered when they said they had a GRP rudder stock. Does anybody know if all Bavarias have that? '' but you don't follow it up with ... 'does anybody know if all Legends have that?'

Does your level of being staggered only relate to certain marques?

Do tell.

 

[sailinglegend420]

QUOTE: "The stock is very obviously flawed and hunter is crazy for continuing to use the same manufacturer. "

Hunter made the original in GRP, the replacements are with a s/s stock made by another supplier.

Try sectioning the stock to see if there are airgaps and layup faults. If so keep having a go at Hunters. When they changed over to s/s they offered all existing customers a discount on a new s/s if they wanted to upgrade, but they don't offer that now to those who have had to but a new one. They have had 19 failures so far, maybe now after several years of "abuse", ie sailing, they will be getting a lot more. Its a shame because the design is great and we love our 420 Passage.

QUOTE: "My rudder sheared from a very light tap."

What was it you actually hit?

 

[KellysEye]

>Does your level of being staggered only relate to certain marques?

I can't believe any keeled yacht builder would fit a GRP rudder stock, hence I was staggered. I can understand building to a price for the family weekend sailing market but that's lunacy.

 

[Bav34]

>Does your level of being staggered only relate to certain marques?

I can't believe any keeled yacht builder would fit a GRP rudder stock, hence I was staggered. I can understand building to a price for the family weekend sailing market but that's lunacy.

Hmmm.

Just seemed to me that when you thought it was a Bavaria the question from you was '' Does anybody know if all Bavarias have that? '' but when corrected you didn't seem staggered enough to ask about the marque in question.

Having just dropped the rudder out ouf my boat for it's 10 year service you can rest easy that the only GRP evident is the rudder itself.

 

[Heckler]

>Does your level of being staggered only relate to certain marques?

I can't believe any keeled yacht builder would fit a GRP rudder stock, hence I was staggered. I can understand building to a price for the family weekend sailing market but that's lunacy.

My 2 benes have figlass stocks
Stu

 

[KellysEye]

>Does anybody know if all Bavarias have that

Sorry, that was a mistake, meant to say Hunter but brain wasn't in gear. Bajansailor did point it out. What would worry me most is what Hunter said:

>Hunter says the use of composites ensured that in a collision, the rudder shaft would fail before the stronger S/S shaft would potentially tear up the bottom of the hull

From what I've read the early rudders didn't have composites. However, with or without composites they are saying they are fitting sacrificial rudders to stop boat damage. Wouldn't it be better to fit a proven SS rudder and strengthen the boat? If people like the boats surely they would pay a bit more for peace of mind.

 

[oldsaltoz]

>
>Hunter says the use of composites ensured that in a collision, the rudder shaft would fail before the stronger S/S shaft would potentially tear up the bottom of the hull

From what I've read the early rudders didn't have composites. However, with or without composites they are saying they are fitting sacrificial rudders to stop boat damage. Wouldn't it be better to fit a proven SS rudder and strengthen the boat? If people like the boats surely they would pay a bit more for peace of mind.

What Hunter are not saying is that a s/steel shaft and extra strengthening will weigh a BIT more, and cost a LOT more.

I'll stick with stainless for now.

Avagoodweekend......

 

[charles_reed]

What Levels of Concern

about rudders - it's probably true to say that all naval architects underestimate the wringing loads on rudders - apart from the produced-down-to-a-price US and European boats, I know of at least 2 Westerlys which suffered rudder breakage, apart from other more expensive boats.

My rudder-blade broke in surf on the Dovey bar (the only MayDay I've ever issued) and in the 23nm sail back to Pwllheli I was able to try out 5 different ways of steering the boat (twin drogues were best and downwind sailing nigh impossible).

The RNLI inshore RIB accompanying me kept on asking me to slow down...

I'd suggest that rudder-loss is a fairly common fault in many boats with spade-rudders and competent seamen should be prepared for it.

 

[KellysEye]

>I'd suggest that rudder-loss is a fairly common fault in many boats with spade-rudders

I think you are right.

I remember being in ten to twelve foot following seas with a three to four foot swell from the north and a two to three foot swell from the south east. When the three met, which was often, the boat wasn't rolling it was a violent corkscrew motion. I dread to think what the rudder loading was. Fortunately our rudder is keel mounted.

Does anybody know if yacht manufacturers publish maximum rudder load? Or has anyone got a copy of the book 'Marine Rudders and Control Surfaces' which might help?

The reason I ask is that knowing the loading for one boat wouldn't mean anything. But a comparison of loadings by boat manufacturer and size would be useful.

 

[@#$% boats]

having a go at hunter

QUOTE: "The stock is very obviously flawed and hunter is crazy for continuing to use the same manufacturer. "

Hunter made the original in GRP, the replacements are with a s/s stock made by another supplier.

Try sectioning the stock to see if there are airgaps and layup faults. If so keep having a go at Hunters. When they changed over to s/s they offered all existing customers a discount on a new s/s if they wanted to upgrade, but they don't offer that now to those who have had to but a new one. They have had 19 failures so far, maybe now after several years of "abuse", ie sailing, they will be getting a lot more. Its a shame because the design is great and we love our 420 Passage.

QUOTE: "My rudder sheared from a very light tap."

What was it you actually hit?

As far as I am aware as hunter pointed me in the direction of their OEM,manufacturer, hunter didnt make the stock.
As I pointed out. I had water coming up through the stock after the rudder had gone. That means water was bubbling up through near two feet of supposedly solid glass. Does that suggest there may be some voids in the stock? Perhaps a manufacturing defect?
Hunter still wont return my emails, The wont even respond to me after emails from my broker who until recently was their dealer.

 

[misterg]

You may care to read the MCIB report on the Hanse rudder that failed in the Irish Sea. Despite extensive testing of the rudder (it was recovered after the sinking) by a specialist firm they were unable to determine the cause of failure.

Sorry late reply, but if you look at one of the letters in the annexe / appendix to the MCIB report, there's a very plausible explanation related to the fitting of the autopilot quadrant roughly mid way between the rudder bearings and at a change in section of the shaft - the bending moment that this induced eventually resulted in a fatigue failure (compounded by a roughly machined shaft) - IMHO.

Andy

 

[charles_reed]

On the subject of steering axes failure

in the '70s I was sales director of a specialist FLT manufacturer, during the start of the narrow-aisle pallet-stacking revolution. We produced and sold, very successfully, a 3-wheel, rotating mast counterbalance truck.

All was well for the 1st 3 years, until there were a spate of rear wheel units overtaking surprised drivers.
Now, as the rear wheel contained the drive motor as well as being the steering wheel and only support for the rear of the truck, it was an indispensable part.

All the fractures had occurred at the end of the machined portion of the 80mm shaft, where the wheel-fork started and the trunnion went into the bearing, just under the steering sprocket.
Typical fatigue fractures, though the machining had been drawn with a radiussed finish to prevent the problem, the machine shop had tightened the radius to get the sprocket to fit.

None of the failures occurred before the trucks had done about 15,000 hours!!!

Which brings me back to the point - everyone with a spade rudder should be prepared for it to fall off, somewhere, sometime, perhaps never (not many boats do 15,000 hrs in rough seas).

 

[Tranona]

Sorry late reply, but if you look at one of the letters in the annexe / appendix to the MCIB report, there's a very plausible explanation related to the fitting of the autopilot quadrant roughly mid way between the rudder bearings and at a change in section of the shaft - the bending moment that this induced eventually resulted in a fatigue failure (compounded by a roughly machined shaft) - IMHO.

Andy

Yes, whilst it seemed a plausible explanation, that was not the finding of the enquiry which did not state a definitive cause.

In some ways, if that were the cause that provides some re-assurance for the integrity of the shafts of spade rudders as the failure was not the result of a design or manufacturing fault.

 

[Tranona]

>

Does anybody know if yacht manufacturers publish maximum rudder load? Or has anyone got a copy of the book 'Marine Rudders and Control Surfaces' which might help?

The reason I ask is that knowing the loading for one boat wouldn't mean anything. But a comparison of loadings by boat manufacturer and size would be useful.

The Irish report on the sinking of the Hanse 371 (which had an aluminium rudder stock, the same as Bavarias). The rudder was designed and manufactured to ABS rules by Jefa a well known supplier to the yacht industry.There was no suggestion the failure was due to design. It failed above the bearings and the rudder and stock fell out. The failure was above the waterline so water entered and slowly sank the boat.

The maths in the ABS standard are a bit beyond me but they do of course take into account forces applied to the rudder. The boat was a sailing school and charter boat and had crossed the Atlantic more than once and the owner expressed complete confidence in its performance.

The natural assumption is that such rudders will fail where the stock exits the hull, either because that is the point of highest load, or as Charles points out a stress point at a machined radius - a potential issue in the Hanse rudder. However this was not the case, although it does seem to be the possible location of failures of Hunter rudders.

One of the difficulties with this subject is that there is very little clear independent information available. The reports I have seen of the Hunter rudders, including photos seem to show failure due to twisting and perhaps failure of the laminate rather than a clean break. The number of failures does seem high, and the apparent change in specification suggests the builder recognises this. On the other hand, once you get away from race boats there seems to be little evidence that spade rudders fail in the way one intuitively thinks they ought to.