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mookiesurfs

Cruising with a spade rudder

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A copy of Ocean Navigator has two 'Old Salts' going on and on about spade rudders being unseaworthy. Hmmmmmm. Personally, I LOVE my balanced spade; to me it is a technological leap forward like electric starters in cars instead of hand cranking. Maybe a small sacrifice to reliability, but a huge leap in performance, safety, and handling.

 

What says the collective SA wisdom? Would you, do you, cruise a spade?

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Wasn't this debate over sometime in the early-mid 1970s :huh:

Spade rudder boats, including my own, have crossed hundreds, thousands, or tens of thousands of open ocean.

How do you think all the Ben-Cat-Huns that charter in the Chesepeake/Maine/New England in the summer and the Islands in the winter get back and forth ;)

That said, a skeg or full keel boat is more damage resistant.

 

 

A copy of Ocean Navigator has two 'Old Salts' going on and on about spade rudders being unseaworthy. Hmmmmmm. Personally, I LOVE my balanced spade; to me it is a technological leap forward like electric starters in cars instead of hand cranking. Maybe a small sacrifice to reliability, but a huge leap in performance, safety, and handling.

 

What says the collective SA wisdom? Would you, do you, cruise a spade?

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On some shoal draft boats, the difference in draft between the keel and the rudder ain't much, and the chances of whacking the rudder on the bottom really increase. The S/D version of the 36.7 comes to mind. Going aground can ruin your entire day ...

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If I were buying a cruising boat, it would almost certainly have a spade rudder..., but:

 

spade rudders can fail from causes other than hitting something.., and,

 

loss of a rudder in the middle of the ocean - say 1000 miles from land - frequently (usually?) results in the boat being abandoned. Most boats do not have effective back-up rudder systems. what they typically have, won't go upwind, won't work in strong winds, and might not work at all. the end result, is that abandonment becomes nearly a necessity.

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Spade rudders are cheap to put on a boat. That is why they put them on cruising boats these days.

 

A skeg rudder steers just fine for a true cruising boat. My Valiant 42 had finger touch steering. It's attaching the hydraulic ram to the post that ruins the feel in a boat alot of the time. With the Alpha autopilot I had on the Valiant, you disconnected the ram when not in use with a plunger. The Sabre 402 that I sailed recently had terrible feel because of the drag of the ram back and forth that you have to fight against. Seems a little silly to perfect the design and feel in a boat, to later ruin it with an option.

 

Also you had to really steer that Sabre with it's hung rudder. Sensitive steering is great for around the bouys, but for passage making the vane or autopilot is steering, so sensitivity just makes the self steering work harder.

 

The skeg adds some directional stability and I like that. Long distance I like the boat to feel like a train on tracks, and I don't care if it tacks easily once every 4 days.

 

My friend hit a rock with his Valiant recently in S. America after missing a marker. As the boat pivoted off, the skeg rudder ground on the rocks for a while. The skeg took the beating and he was able to continue down the coast to a yard. Same thing happened to another friend on his Crealock 34 in the S. Pacific a few weeks ago. Put his rudder on a coral head. Both of these guys claim that a spade rudder would have broke, stranding them in a place far away from a boat yard with no way to steer their boats. Both of these guys are expert cruisers, and do their best to stay off the bottom. You know what they say..."there are only two kinds of sailors,,those who have gone aground, and those who are lying" Shit happens.

 

Another friend is buying a Hallberg Rassy 39 in a couple of weeks. That boat has a half skeg and strong connection points. Maybe that is a good compromise. You get the ballanced rudder with more support 1/4 way up if you crunch the bottom.

 

For dual purpose coastal cruisers, hung rudders are adequate I think. For serious passagemakers that are out in the middle of nowhere all the time, a protected rudder seems to make more since.

 

Offshore racing boats don't spend much time gunkholing and sticking their nose into every marginally shallow cove like cruisers do, so they are less likely to put their rudder on a rock.

 

For true offshore passagemaking and cruising, I think you get more then you give up by having a supported rudder.

 

That said, while out cruising I see every concievable contraption of a boat out there, and most all seem to be doing just fine with whatever style rudder or wierd boat they have. In the end, it's more about the Capt. then the boat.

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A partially balanced spade with a carbon stock and blade can be extremely strong. This would be my choice on a boat over 40'.

Under 40' where helm pressures are less you can do an unbalanced rudder on a skeg. The rudder will not work as well as a spade but you may at least feel safer. Skegs are hard to build in grp molded boats and not always strong. I have been doing a few partial skeg hung rudders where I think you get the best of both worlds, i.e. a lower bearing for strength and some balance area to offset helm presure. Remember, the stock for a spade ruder has to be engineered for both bending and twisting moments while a skeg hung rudder is engineered only for twisting moments. So, a spade rudder will have a much bigger stock than a rudder of roughly the same size with a skeg. It has always bothered me to have a critical bearing right at the bottom of the skeg where you would be most likely to bang it.

 

In the end I think it boils down to personal preference. Pick the rudder config you like then do it right and understand the trade offs.

Boats with spade rudders almost alwasy are easier to drive in reverse and will steer better at low speeds.

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Quote: "Both of these guys claim that a spade rudder would have broke, stranding them in a place far away from a boat yard with no way to steer their boats. Both of these guys are expert cruisers..."

 

If they were "expert cruisers", whatever that means, wouldn't they have a way to rig a jury rudder, know how to make the boat steer with only sails, or know how to heave to until they could figure something out? You need to be prepared to deal with these things no matter what your rudder configuration.

 

If you're limping into port, under power, using a jury rudder, you'll need less mechanical advantage to steer most spade-rudder boats.

 

The advantages of a spade rudder are worth it, to me, in exchange for a maybe bigger chance of having to deal with a failure.

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If you're limping into port, under power, using a jury rudder, you'll need less mechanical advantage to steer most spade-rudder boats.

 

If you're limping into port, under power, using a jury rudder, it's pretty likely that none of your jury rig will involve the spade rudder because all or a major part of the rudder will be at the bottom of the ocean. Many times when they fail, it's the rudder post that snaps and the entire rudder sinks into the blue. Hunters in particular have had a problem with this, sometimes without the benefit of even hitting anything.

 

Spade rudders can be built quite strong, but the fact is that spade rudders for many production boat rudders aren't. And I think this fact is the point of contention.

 

I don't think you can talk about spade rudders generically because the build strength varies so much. It's like saying masthead rigs are stronger. Makes no sense in the abstract because it's both true and false, depending.

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If you're limping into port, under power, using a jury rudder, you'll need less mechanical advantage to steer most spade-rudder boats.

 

If you're limping into port, under power, using a jury rudder, it's pretty likely that none of your jury rig will involve the spade rudder because all or a major part of the rudder will be at the bottom of the ocean. Many times when they fail, it's the rudder post that snaps and the entire rudder sinks into the blue. Hunters in particular have had a problem with this, sometimes without the benefit of even hitting anything.

 

Spade rudders can be built quite strong, but the fact is that spade rudders for many production boat rudders aren't. And I think this fact is the point of contention.

 

I don't think you can talk about spade rudders generically because the build strength varies so much. It's like saying masthead rigs are stronger. Makes no sense in the abstract because it's both true and false, depending.

 

 

That and how the rudder mount works - rudder fails in a big way are you at risk of having a large hole in your otherwise sealed hull? Back up rudder system thats tested - deployed and useable in less than ideal conditions is a must!

 

Reviewing your rudder set up so that you can either do preventitive work to prevent hull damage when rudder fails or isolate the rudder post area to eliminate the threat of sinking etc.

 

Remember a while back a well cruised J44 losts its rudder - crew struggled with it for quite some time but eventually gave up and abandonded the boat due to fatigue and the threat of weather etc. A case where a pretty good boat suffered the ultimate fate due to a rudder failure. Had they had a good alternate thought out they may have been just fine.

 

One of our SA sailors ID35 or something like that lost a rudder and had a hole to deal with they managed to save the boat with a nerf foot ball - great save and fast thinking! But cruiser you need to have more advanced plans for that.

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Dear Valued Hunter 450/456/460/466/46 Owner:

Seasoned offshore sailors understand and appreciate the fact that rudders are designed and

manufactured to protect the hull of the boat from serious under-water damage. Over the past several

years, we have received reports from some owners who have inadvertently lost their fiberglass

composite post rudders during boating activity. Our goal with this communication is to explain how this

loss might occur and to provide you with recommendations for enhanced maintenance options, plus

encourage ongoing safety education for captain and crew alike in the case of rudder loss.

 

By virtue of its design, whenever a boat runs aground, or when the rudder strikes or is struck by an

object, there is always a chance that the rudder post has been compromised or weakened to some

extent. This weakening may go undetected, and may only become evident after continued or extensive

use, possibly in adverse conditions.

 

While Hunter Marine’s limited warranty specifically does not warrant the rudder because of the

significant linkage to boat operation, it has always been Hunter Marine’s policy to examine rudder

stocks where there has been a rudder loss, whenever possible. Our goal in analyzing rudder loss is to

determine cause and continually seek methods of improvement in our approach to design and

manufacturing.

 

Specifically, Hunter Marine is aware of 16 rudders which have been lost on boats within your size

range, most of which had been in use for more than two years. We were able to review 13 of the

16 reported. Our research indicates that 11 were well within the design and manufacturing

tolerances. One rudder post may have had a manufacturing problem, while another was within the

design tolerance but did not meet Hunter’s internal tolerance specifications.

 

http://www.huntermarine.com/SafetyTuneUp/H...r2007TuneUp.pdf

 

The concern about spade rudders is no idle concern. If I understand Hunter correctly, most of these rudder failures were within their parameters and nothing was wrong with the rudder, other than the fact that they failed.

 

Further, I think in their first sentence above they said that the rudder is designed to fail in order to save the hull from damage. I know at one time Bruce Roberts, the steel boat designer, was advocating a similar design approach.

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Would you . . . cruise a spade?

 

Yes, depending on how well it was designed and built. Which translated means, no, quite a bit of the time.

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Has Bob chimed in yet? I suspect the ideal mix is a spad type ruder with some level of skeg factored in as being the nicest mix of performance and durablity for the worst case cenario. Thats what I always figured anway.

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Nearly 2000 Swans have been built since 1966. Pretty well every one built since 1979 (with the exception of the last S&S 57s, 47s and a few late 65s) has had a spade rudder. Figure 1500 boats. And they've done lots and lots and lots and lots of cruising miles. Sure there were some early rudder failures (Casse Tete in the 79 Fastnet for example), but modern failures are about as rare as rocking horse shit.

 

But then again, the rudders are built like a brick shithouse. But yours should be too.

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Has Bob chimed in yet? I suspect the ideal mix is a spad type ruder with some level of skeg factored in as being the nicest mix of performance and durablity for the worst case cenario. Thats what I always figured anway.

Spad???

post-25282-1224207163_thumb.jpg

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Quote: "Both of these guys claim that a spade rudder would have broke, stranding them in a place far away from a boat yard with no way to steer their boats. Both of these guys are expert cruisers..."

 

If they were "expert cruisers", whatever that means, wouldn't they have a way to rig a jury rudder, know how to make the boat steer with only sails, or know how to heave to until they could figure something out? You need to be prepared to deal with these things no matter what your rudder configuration.

 

If you're limping into port, under power, using a jury rudder, you'll need less mechanical advantage to steer most spade-rudder boats.

 

The advantages of a spade rudder are worth it, to me, in exchange for a maybe bigger chance of having to deal with a failure.

 

 

It turns out that by and large, the methods of jerry rigging a rudder, won't get you 1000 or 2000 miles - that's why the boats get abandoned.

 

Really, the only way to do this, is to have a "real" emergency rudder made up, and a strong pintle system mounted on the stern - but few poeple do this.

 

the situation is doubly bad for a spade rudder boat, because generally there is _nothing_ left at the stern to help the boat track. i've been on boats preparing for newport-bermuda, and similar races, where some sort of rube-goldberg system gets "tested". usually what they do, is first lock off the wheel - well, now the boat tracks great!!! any system will steer the boat in the flat water and light wind where this experiment is typically conducted. when theer is nothing there, it's going to be a different matter.

 

So, picture yourself 1000 miles into a 3000 mile atlantic crossing - it was work to steer the boat down the big waves even with the ruudder. now, it is completely gone. you might manage to jerry rig something, but it is barely working in nice weather at a boat speed of maybe 5kts, and the boat still gets turned broadside to the waves fairly frequently - not a huge problem, as long as there's not a storm, with breaking waves. but, you've got 2000 miles to go..., (no, you can't turn around and go upwind - you will never be able to steer on that point of sail) the chance of at least one storm is pretty good.

 

most people in this situation, elect to get off on to the first passing freighter.

 

there's no salvage in the middle of the ocean.

 

i would choose a spade rudder, with a very sturdy, purpose-built, emergency rudder - with a strong mounting system pre-installed on the transom.

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On some shoal draft boats, the difference in draft between the keel and the rudder ain't much, and the chances of whacking the rudder on the bottom really increase. The S/D version of the 36.7 comes to mind. Going aground can ruin your entire day ...

 

109 is like that too. Almost no depth difference between the rudder and the bottom of the SD keel.

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Rudder failure underway seems like less of a concern than rudder damage by grounding. Groundings are a reality while cruising, which is why we go offshore right? Spade rudders and some keg designs are very vulnerable to damage from even light/moderate groundings. Even if they are not sheared off, a sharp jolt upwards (like can happen when you pick a bad spot to anchor and the tide goes out or a swell rolls in) can damage the bearings and jam the rudder, or damage the quadrant with similar results. I have personally seen damage from groundings and known people that lost their rudders for a variety of reasons, none of which would have caused any trouble for a full keel or a properly constructed full skeg.

There are designs that I would consider, particularly those with a sacrificial lower portion of the rudder, but these are by far not the norm and certainly not found on any boat in my price range.

 

Jury rigs have been mentioned. I use the hydrovane and can testify to its ability to completely handle steerage if needed. I locked my rudder and sailed around in 20 knots and then docked under power just using the windvane rudder. Very stout and powerful gear! I can even use it it back my vessel when the main rudder is completely useless. Unlike Mrud and similar systems the hydrovane is a real auxiliary rudder 100% of the time, no extra parts needed. I would chose a system like this to serve as an emergency rudder.

 

Another benefit of a full keeler is there is virtually no chance of fouling the rudder and minimal chance of fouling the prop in kelp or from fishing gear. Can't say how many times I cut Pt. Loma short not giving a shit about the kelp beds! Its like a free hull cleaning :)

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Rudder failure underway seems like less of a concern than rudder damage by grounding. Groundings are a reality while cruising, which is why we go offshore right? Spade rudders and some keg designs are very vulnerable to damage from even light/moderate groundings. Even if they are not sheared off, a sharp jolt upwards (like can happen when you pick a bad spot to anchor and the tide goes out or a swell rolls in) can damage the bearings and jam the rudder, or damage the quadrant with similar results. I have personally seen damage from groundings and known people that lost their rudders for a variety of reasons, none of which would have caused any trouble for a full keel or a properly constructed full skeg.

There are designs that I would consider, particularly those with a sacrificial lower portion of the rudder, but these are by far not the norm and certainly not found on any boat in my price range.

 

Jury rigs have been mentioned. I use the hydrovane and can testify to its ability to completely handle steerage if needed. I locked my rudder and sailed around in 20 knots and then docked under power just using the windvane rudder. Very stout and powerful gear! I can even use it it back my vessel when the main rudder is completely useless. Unlike Mrud and similar systems the hydrovane is a real auxiliary rudder 100% of the time, no extra parts needed. I would chose a system like this to serve as an emergency rudder.

 

Another benefit of a full keeler is there is virtually no chance of fouling the rudder and minimal chance of fouling the prop in kelp or from fishing gear. Can't say how many times I cut Pt. Loma short not giving a shit about the kelp beds! Its like a free hull cleaning :)

 

Out of interest (not dissing it at all), do you know how it would handle your boat if there was no rudder? That's a very different situation from steering the boat with the rudder fixed centrally as its balancing the boat for you etc.

 

Worst situation I had with a rudder was on a very high tech old IOR boat on a delivery where the tiller pulled of the top of the stock, stock then sank down a few inches so the tiller could not be re-attached. It was absolutely impossible to use any emergency steerage with the rudder flopping around. The fix was to hammer a bunch of screwdrivers into the top of the stock and lash the tiller to them.

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Out of interest (not dissing it at all), do you know how it would handle your boat if there was no rudder? That's a very different situation from steering the boat with the rudder fixed centrally as its balancing the boat for you etc.

 

I think *my* boat would handle quite well since it is full keel. The hydrovane is powerful enough to completely override the main rudder if you hook it up backwards. Don't ask. Hydrovane claims that since the auxiliary blade is positioned so far aft that its power due to this extra leverage is more than adequate for most boats. Considering they sell the same model for all boats into the mid 40's (I bought mine used from an Endeavour 45) I have no doubt that this model self steering could satisfactorily steer a fin keel boat of a modest passage maker size. You won't be flying a kite, and you might be forced to pay a lot more attention to your sails but there isn't any good reason you couldn't get home. Only excuses like "I could only go 4 knots," "We had to hand steer all the time" or some other such silliness. I think this system is the next best thing to a real emergency auxiliary rudder that could be fitted to gudgeons. Of course with cruisers trending to modern electronic autopilots a $8,000 windvane probably isn't all that appealing for most people.

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A partially balanced spade with a carbon stock and blade can be extremely strong. This would be my choice on a boat over 40'.

Under 40' where helm pressures are less you can do an unbalanced rudder on a skeg. The rudder will not work as well as a spade but you may at least feel safer. Skegs are hard to build in grp molded boats and not always strong. I have been doing a few partial skeg hung rudders where I think you get the best of both worlds, i.e. a lower bearing for strength and some balance area to offset helm presure. Remember, the stock for a spade ruder has to be engineered for both bending and twisting moments while a skeg hung rudder is engineered only for twisting moments. So, a spade rudder will have a much bigger stock than a rudder of roughly the same size with a skeg. It has always bothered me to have a critical bearing right at the bottom of the skeg where you would be most likely to bang it.

 

In the end I think it boils down to personal preference. Pick the rudder config you like then do it right and understand the trade offs.

Boats with spade rudders almost alwasy are easier to drive in reverse and will steer better at low speeds.

 

A question to Mr. Perry if I may:-

 

My 4ksb (East Coast 31 designed by Peter Cole) has a skeg hung rudder, however the rudder shaft is raked aft at about 10 degrees. I've been told this is to lighten the helm. Does raking the rudder shaft really help with this?

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C28:

So by raked 10 degrees you mean the lower end of your stock is further aft than the upper end. Right?

Or, the other way around?

I don't know how that would effect helm pressure. But inquiring minds want to know.

So here is what I did:

I drew two indentical rudder/skeg combos.

I gave the rudder a strict rectangluar planform for simplicity.

I measured the distance from the center of the rectangle to the rudder stock, it came up 1.5 on the vertical stock ruddder.

I then raked one rudder aft 10 dgrees and measured the distance from the center of the blade to the stock again and this time it was 1.55.

So, at least with my example the "arm" increased with the ten degree rake and that would indicate to me you would have more helm pressure.If I raked the rudder the other way 10 degres there was a corresponding reduction in the arm. But in both cases the change was quite small.

This is no doubt an overly simplified 2D geometry test of a dynamic 3D situation so the value of it may not be much.

I generally rake my spade rudders about ten degrees or to an angle that would keep the rudder stock roughly perpendicular to the flow of the water at the rudder. At the same time, if you have relatively flat sections at the rudder stock the right rake angle can insure that the top of the rudder blade stays close to the hull as the rudder turns and this would help to keep the flow over the rudder attached. Most modern boats have their rudder stock approximately perpendicular to the hull profile at the stock.

 

Often pragmatic issues may dictate how the ruuder stock is raked. The designer may know where he wants the rudder but interior joinery (aft berth) or cockpit configuration (wheel position/ seat edge) may require the stock head to be moved. So in a case like this the designer may add rake to get the stock head where he wants it while keeping the bulk of the rudder blade where he wants it.

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C28:

So by raked 10 degrees you mean the lower end of your stock is further aft than the upper end. Right?

Or, the other way around?

I don't know how that would effect helm pressure. But inquiring minds want to know.

So here is what I did:

I drew two indentical rudder/skeg combos.

I gave the rudder a strict rectangluar planform for simplicity.

I measured the distance from the center of the rectangle to the rudder stock, it came up 1.5 on the vertical stock ruddder.

I then raked one rudder aft 10 dgrees and measured the distance from the center of the blade to the stock again and this time it was 1.55.

So, at least with my example the "arm" increased with the ten degree rake and that would indicate to me you would have more helm pressure.If I raked the rudder the other way 10 degres there was a corresponding reduction in the arm. But in both cases the change was quite small.

This is no doubt an overly simplified 2D geometry test of a dynamic 3D situation so the value of it may not be much.

I generally rake my spade rudders about ten degrees or to an angle that would keep the rudder stock roughly perpendicular to the flow of the water at the rudder. At the same time, if you have relatively flat sections at the rudder stock the right rake angle can insure that the top of the rudder blade stays close to the hull as the rudder turns and this would help to keep the flow over the rudder attached. Most modern boats have their rudder stock approximately perpendicular to the hull profile at the stock.

 

Often pragmatic issues may dictate how the ruuder stock is raked. The designer may know where he wants the rudder but interior joinery (aft berth) or cockpit configuration (wheel position/ seat edge) may require the stock head to be moved. So in a case like this the designer may add rake to get the stock head where he wants it while keeping the bulk of the rudder blade where he wants it.

 

Thanks for such a comprehensive reply.

Looking at the layout now I can see it's as you say. The stockhead comes through the cockpit floor at the very aft end, under a seat edge and out of the way.

There was no consideration on keeping the rudder blade near the hull on such a heavy old pintail half-tonner like this,

Thanks again for the response.

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Just saw this on yachtworld.. reminded me of this thread.

 

1864756_14.jpg

 

 

looks like fun :) My boat came with one of the wood floor Avons that had a floor panel with couple holes drilled in it. In one of the drawers I found a couple rusty u-bolts in a ziploc bag..

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Dear Valued Hunter 450/456/460/466/46 Owner:

Specifically, Hunter Marine is aware of 16 rudders which have been lost on boats within your size

range, most of which had been in use for more than two years.

 

I don't think the failure rate of Hunter rudders can be used as credible evidence that spade rudders are generally weak. Some might say it is strong evidence that Hunter rudders are weak.

 

As Bob says, you should really look at how a skeg hung rudder is made in a GRP hull. It is quite easy to laminate a very strong rudderstock, and quite difficult to laminate a very strong skeg. In steel or aluminum (or even wood) the skeg can be easily made as strong as desired.

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Just saw this on yachtworld.. reminded me of this thread.

 

1864756_14.jpg

 

 

looks like fun :) My boat came with one of the wood floor Avons that had a floor panel with couple holes drilled in it. In one of the drawers I found a couple rusty u-bolts in a ziploc bag..

 

 

I doubt these things would work for more than a few miles, and only in the best conditions.

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I think partial skegs offer the best of both worlds..My steering is finger light and balanced I have sailed in over 40 kt winds...albeit here in Puget sound with no swell to deal with but light and sensitive non the less.

 

Wanting to qualify to this years Swiftsure this topic is relevet to me as one of the many requirements I have to prove is some means of an adequate emergency rudder system.

 

I am leaning toward a copy of a version I saw once which mounts a box on pintals on the stern in which you would then later insert the rudder into if needed.. I believe it would even be possible to have stern penetrations for cabling to hook up to your existing quadrant or stering system...I will find out as I proceed with the design.

 

Other then the beefy pintles mounted to the stern everything is otherwise removable when not required for for a race or when crossing the blue.

post-25663-1224437107_thumb.jpg

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this is why sailboats need twin engines and props!

 

I hope you are kidding...I already spend way too much time maintaining one drive system that makes me VERY happy to shut down, let alone doubling it.

 

Dan

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I don't think the failure rate of Hunter rudders can be used as credible evidence that spade rudders are generally weak.

 

I agree.

 

I wasn't using the failure rate of Hunter's rudders to indict spade rudders in general, but rather to underscore my point that I don't think anyone can talk intelligently about spade rudders in the abstract because the design and build quality is all over the map.

 

I don't think you can talk about spade rudders generically because the build strength varies so much. It's like saying masthead rigs are stronger. Makes no sense in the abstract because it's both true and false, depending.

 

Hunter's experiences with their rudders (and their ever so quiet recall they seem to have going) is a real counterbalance to those who say spade rudders are a closed issue, thousands of spade rudders have crossed thousands of oceans and therefore spade rudders are OK. It's just not that simple. Like most things in life the correct answer is, "It depends."

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If I extrapolated my experience aboard Hunters to boats in general, I would have to say never go offshore in a fiberglass boat with aluminum spars, dacron sails, batteries, and an engine :o:lol:

 

I don't think the failure rate of Hunter rudders can be used as credible evidence that spade rudders are generally weak.

 

I agree.

 

I wasn't using the failure rate of Hunter's rudders to indict spade rudders in general, but rather to underscore my point that I don't think anyone can talk intelligently about spade rudders in the abstract because the design and build quality is all over the map.

 

I don't think you can talk about spade rudders generically because the build strength varies so much. It's like saying masthead rigs are stronger. Makes no sense in the abstract because it's both true and false, depending.

 

Hunter's experiences with their rudders (and their ever so quiet recall they seem to have going) is a real counterbalance to those who say spade rudders are a closed issue, thousands of spade rudders have crossed thousands of oceans and therefore spade rudders are OK. It's just not that simple. Like most things in life the correct answer is, "It depends."

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Hunter's experiences with their rudders (and their ever so quiet recall they seem to have going) is a real counterbalance to those who say spade rudders are a closed issue, thousands of spade rudders have crossed thousands of oceans and therefore spade rudders are OK. It's just not that simple. Like most things in life the correct answer is, "It depends."

I think the bottom line is that if you travel to distant shores you should be reasonably prepared to handle emergencies. Loss of steering *might* be more probable, certainly more serious, with a spade than skeg or barn door rudders & their respective hull designs so your preparation should be adjusted accordingly. Specifically for spade rudders, account for more loss of control and the need for a stronger and more effective emergency steering device than more conventional designs might need. Also you need to account for the possible loss of the largerrudder stock with the potential for rather serious flooding. In all cases for God's sake be able to get home. This last years rash of hitting the eject button (EPIRB) for perfectly serviceable floating & sail-able boats was disturbing to say the least.

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Here's an interesting little rudder story . I was talking to a cruiser a couple of years ago and he was telling me about bringing a boat ( a south pacific 42? I don't know American boats too well) back from the US to here ,NZ. Out of Fiji on passage here they lost the skeg off the boat... noticed that the rudder was flexing and bad noises etc . On diving they discovered that the whole skeg had just dropped off... said something about it being bolted on and those bolts had sheared ,crevice corrosion or whatever.

Anyway, the bit I found interesting was that they had to drop the rudder out ( it couldn't live there ) which they did ,but no matter what configuration they came up with for jury steerage ,they just couldn't get the boat to steer. Thats because the skeg was part of the lateral plane and without it , the boat just kept rounding up.

Fortunately they were cruising with another boat so they towed it with all their chain etc out as the tow warp and sails set. That held the bow on course and they tow sailed it something like 400 odd miles back here( or was it from 400 out of Fiji) Long way anyway.

 

 

 

far out, I didn't write any of that in my profile. Not that I mind,,, I just didn't do it.

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South Pacific 42 is my design. I'm skeptical as to the reason they could not get the boat to steer. I'll tell another story.

NIGHT RUNNER was cruising of the coast of Mexico when the skeg "fell off". They continued on with the rudder hanging free.

I asked the owner how the boat steered without the skeg, "Much better" he said.

 

I don't doubt the SoPac owners had problems rigging effective jury steering but I don't think it had anything to do with the lateral area of the skeg. If that boat had a spade rudder it would have been just about as big as the skeg hung rudder.

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Hmm, thats what he told me anyway Bob. and maybe I've absorbed the SP42 name from your book. As far as I recall it he bought it from florida thereabouts.

He described the rudder and stock starting to slog around without the skeg support so they dropped it out the bottom and lashed it to the pushpit. I gather the whole stock location area had its own bulkhead and was safe.

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Ok Im a little confused here...My skeg is solidly glassed in as part of the hull..I dont see it just falling off...what am I missing here?

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He described the rudder and stock starting to slog around without the skeg support so they dropped it out the bottom and lashed it to the pushpit.

 

"pushpit"...can't one of Bob's.

 

Dan

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Ok Im a little confused here...My skeg is solidly glassed in as part of the hull..I dont see it just falling off...what am I missing here?

This is the problem. Just as you cannot say a spade rudder is good ("it depends") you cannot say a skeg rudder is good - it depends.

 

A skeg is a horrible thing to laminate in a female production mold. You are stuffing glass down there blind with a stick, slopping resin in hoping it is going in the right place. You are two feet down a hole 4 inches wide. Quality is not possible. A few boats are done in two halves, then glued together. Again very difficult to asses the glue joint created that deep in a hole, and the two halves by themselves are not particularly strong.

 

Not just a few boats with skegs have them molded separately and then glued on after the fact. At least you know what you have created then, but it is usually a secondary polyester bond in a production boat.

 

Contrast that with a properly built carbon rudderstock, which would be vacuum bagged and autoclaved, with fibers oriented the best way to resist the forces involved in the full light of day - not stuffed in with a stick blind.

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Ok Im a little confused here...My skeg is solidly glassed in as part of the hull..I dont see it just falling off...what am I missing here?

This is the problem. Just as you cannot say a spade rudder is good ("it depends") you cannot say a skeg rudder is good - it depends.

 

A skeg is a horrible thing to laminate in a female production mold. You are stuffing glass down there blind with a stick, slopping resin in hoping it is going in the right place. You are two feet down a hole 4 inches wide. Quality is not possible. A few boats are done in two halves, then glued together. Again very difficult to asses the glue joint created that deep in a hole, and the two halves by themselves are not particularly strong.

 

Not just a few boats with skegs have them molded separately and then glued on after the fact. At least you know what you have created then, but it is usually a secondary polyester bond in a production boat.

 

Contrast that with a properly built carbon rudderstock, which would be vacuum bagged and autoclaved, with fibers oriented the best way to resist the forces involved in the full light of day - not stuffed in with a stick blind.

 

 

 

Sometimes ignorance is/was truly bliss.............................Thanks.....I think....... ;)

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Interestingly, in Steve Dashew's latest post, he bags on a partial skeg, saying he much prefers a spade rudder - scroll down about 3/4 of the page:

 

Dashew on rudders

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He described the rudder and stock starting to slog around without the skeg support so they dropped it out the bottom and lashed it to the pushpit.

 

"pushpit"...can't one of Bob's.

 

Dan

 

What do you call em?

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A skeg is a horrible thing to laminate in a female production mold. You are stuffing glass down there blind with a stick, slopping resin in hoping it is going in the right place. You are two feet down a hole 4 inches wide. Quality is not possible. A few boats are done in two halves, then glued together. Again very difficult to asses the glue joint created that deep in a hole, and the two halves by themselves are not particularly strong.

 

I agree. This is why skegs should be welded on. :P

 

Seriously, execution is 70% of the answer. All steerage systems can be poorly implemented. All it takes is the goal of cost reduction.

 

Contrast that with a properly built carbon rudderstock, which would be vacuum bagged and autoclaved, with fibers oriented the best way to resist the forces involved in the full light of day - not stuffed in with a stick blind.

 

How many production boats have your mythical spade rudder set up? Not many. There's the rub.

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[slight hijack]

 

you know, I'd never heard the term 'pushpit' until I came to SA...I always called them 'stern pulpits' also :lol:

 

[/hijack]

 

Bob does monocoque mean one piece ?? Like the whole rudder & stock are a single structure?

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One of the most talented people at our club built a new rudder for his (racing) Express30...he incorperated a carbon shaft and I believe epoxy over foam for rudder itself. It was simply a work of art.

 

The weight difference was amazing but because it was so light, it always made me feel it was not as solid...guess I was wrong.

 

Dan

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Hike:

Yes. The stock is built up in a shape, thru the rudder blade , with flattened sides to comform to the foil shape of the rudder blade. Foam is added to the stock, aft of the stock only and the carbon is wrapped around the stock and the foam, bonding the aft portion of the blade to the stock. Then foam is added to define the area forward of the stock, the leading edge, and carbon is again wrapped around that and back onto the blade area, usually around the entire blade. In the end you have a one piece unit, stock and blade. The carbon skins add signifigantly to the strength of the stock but are, in my case, not included into the structural calculations for stock dimensions. In a case like for a AC boat you might include the strength added by the skins just so more weight can be reduced. But for cruising boats I think it makes sense to be very conservative with rudder and stock specs.

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Carbon rudders.. what is the world coming too? Sounds cool but I got a few questions.

How much would it cost if one introduced their carbon rudder blade to a coral head?? Could you fix it yourself? Are there any additional electrolysis issues with a carbon blade & stock?

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Hike:

Yes. The stock is built up in a shape, thru the rudder blade , with flattened sides to comform to the foil shape of the rudder blade. Foam is added to the stock, aft of the stock only and the carbon is wrapped around the stock and the foam, bonding the aft portion of the blade to the stock. Then foam is added to define the area forward of the stock, the leading edge, and carbon is again wrapped around that and back onto the blade area, usually around the entire blade. In the end you have a one piece unit, stock and blade.

 

This could be money well spent if one were planning to take a production boat like my Catalina offshore. Certainly some boat bucks spent on a custom rudder up front would be preferable to losing the rudder, endangering lives and the boat later on. Seems even if appropriately designed and built, production rudders can weaken over time due to water infiltration and corrosion.

 

Bob, if you had to make a wild guess, what might it cost to have such a replacement rudder engineered and built for your basic 35 to 40 foot production boat with spade rudder? Thanks.

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Thanks Bob, your regular english answers are always appreciated.

 

CJ, my only concern there (using a Catalina as an example since I have one myself) might be that the rudder is built so well, it might just rip a hole in the boat. :o

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Cruiser Jim:

I would guess around 7 to $9,000 but why guess when you could contact Phil's Foils (an SA advertiser) and ask them directly. They just did a new rudder for one of my Mirages.

 

Hike:

I hear you on that and if you were to take a direct hit to a well built carbon rudder there could be damage done to the surrounding area I suppose. But the area around the rudder port is usually well built up and reinforced with a series of gussets to spread the stock loads out. I also like to se the stock taken up to an upper bearing located at the cockpit sole or the cocpit seat level. his would further spread the impact load out. I have never heard of hull damage from a rudder hit.

 

Just for you: Ni bu fung shing. Mayo wentee. ( a non English answer)

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Here is an example of a carbon spade rudder design. I hope the details show up at this resolution.

Note in this example the ruder stock is round and not shaped to fit the rudder blade.

 

 

HAWKRUDDER_.pdf

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Bob

 

Is a gaiter the proper name for a steering shaft, stuffing box??

 

Dan

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Slow:

Do you have a spade rudder on that old Islander?

 

No.. inefficient and clumsy old barn door with an overly large aperture on an old Rawson.

 

rrwRun1.jpg

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He described the rudder and stock starting to slog around without the skeg support so they dropped it out the bottom and lashed it to the pushpit.

 

"pushpit"...can't one of Bob's.

 

Dan

 

I've always called it a pushpit.

 

[interesting fact of the day] The pulpit was invented by Austin "Clarance" Farrar in 1936, for the yacht Ortac. [/interesting fact of the day]

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I hear you on that and if you were to take a direct hit to a well built carbon rudder there could be damage done to the surrounding area I suppose. But the area around the rudder port is usually well built up and reinforced with a series of gussets to spread the stock loads out. I also like to se the stock taken up to an upper bearing located at the cockpit sole or the cocpit seat level. his would further spread the impact load out. I have never heard of hull damage from a rudder hit.

 

Thanks Bob. Yes I have 4 large gussets and an upper bearing at the cockpit sole, the weak link is definitely the rudder itself, especially as it gets older.

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Cruiser ( sorry Slow)

Nothing lasts forever. If you like I'd be happy to tell you what stock diameter to use but it may require a new tube and bearing.

You can send me a bottle of Scotch.

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Cruiser ( sorry Slow)

Nothing lasts forever. If you like I'd be happy to tell you what stock diameter to use but it may require a new tube and bearing.

You can send me a bottle of Scotch.

 

Bob

 

Our M33 has no upper bearing...can this be added at this time?? If so is it worth my effort knowing what Jill and I use her for.

 

Dan

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For more than 10 years, every time my boat was in the yard at Svendsen's, Carl Schumaker would walk out from his office, put his hand on my shoulder and ask "Why does such a fast boat have such a slow rudder?". Carl and I always talked about whacking the skeg off and building a high-performance spade but then ... he died.

 

Let's enumerate the advantages of a skeg-hung rudder:

None

 

Now, let's enumerate the disadvantages:

Adds wetted surface

Largely prevents steering when backing

Is unbalanced and so requires high steering effort from the helmsman or helmswoman

Is unbalanced and so requires high steering effort (read high energy demands) from the auto pilot

Generates lots of drag and nearly no lift

Reduces the boat's turning radius, which is a real drag (no pun) when mark rounding, in pre-start sparring and in tight quarters (i.e. turning into a slip)

Prevents removal of the prop shaft

 

I know of no qualified designer who believes that there is any merit to a skeg-hung rudder given the materials available today.

 

My skeg and rudder are both 36 years old and their time has come. I've got a designer working on a balanced blade design, which will be a carbon rudder stock with a carbon-over-foam blade. I'll haul the boat in New Zealand in March and personally take a chain saw to the old skeg. The new installation will likely use Jeffa bearings. It will be moved forward from the old position so that it's profile is approximately centered in the combined profile of the old rudder blade and the skeg.

 

Estimated costs are:

$1200 - design

$3000 - Bearings, seals, etc

$4000 - Blade construction

$6000 - Skeg removal, fairing, closing old rudder stock hole, installing new rudder stock tube, re-routing steering cables and repositioning auto pilot

 

All estimates are in US dollars, gotta love the current exchange rate on the Kiwi dollar.

 

Photos and updates as it happens.

 

Wish me luck!

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Mooner:

I hope you check back in with us and tell us how the boat feels with the new rudder.

Good on ya. I think you are going to love it.

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Mooner:

I hope you check back in with us and tell us how the boat feels with the new rudder.

Good on ya. I think you are going to love it.

 

 

For us relatively new what boat does he have?..it's not listed in his profile.

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Hike:

Yes. The stock is built up in a shape, thru the rudder blade , with flattened sides to comform to the foil shape of the rudder blade. Foam is added to the stock, aft of the stock only and the carbon is wrapped around the stock and the foam, bonding the aft portion of the blade to the stock. Then foam is added to define the area forward of the stock, the leading edge, and carbon is again wrapped around that and back onto the blade area, usually around the entire blade. In the end you have a one piece unit, stock and blade.

This is about how my rudder was built. Conventionally built (SS tube, welded on tabs, fiberglass skins) it was estimated to weigh 300 lbs. As built, 94 lbs and far stronger. Light enough that it floats and the thrust bearing must hold it down - not up.

 

Other than the post, which might be beyond the average DIY (but can be purchased commercially), the rest of it could be done in your garage. It isn't even that expensive - the real issue lies with the consumer who asks price first and almost never about the strength of the rudder.

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Wayne, when you build your new one, rebate the foam around the leading edge and fill it in with some white glass before you wrap the carbon skins. Makes the leading edge much tougher for whacking things without much additional cost or effort (weighs a little though, but won't matter considering all the stuff you are sawing off). On mine we added abut 1/4" all down the leading edge and around the tip. Also kept the post almost two feet off the bottom on the theory that in a really hard grounding that would break off first, sacrificing the tip but not the rest of the steering system.

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Let's enumerate the advantages of a skeg-hung rudder:

None

 

My last boat had a high aspect, balanced spade rudder. If the helm was thrown over in a "crash" avoidance maneuver it would TOTALLY stall and loose all effectiveness.

 

My current boat has a rudder with a full skeg and it seems to be impossible to stall the thing. Backs very well, too, which is a point that Bob made.

 

So I don't agree that skegs lack any merits.

 

Owen

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Owen:

All spade rudders are not created equal. Your skeg hung rudder probably was limited to 30 to 40 degrees each side of centerline. Your spade did not have that limit so the difference was not in the rudder iself but how yu drove the boat. Does that make sense?

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Owen:

All spade rudders are not created equal. Your skeg hung rudder probably was limited to 30 to 40 degrees each side of centerline. Your spade did not have that limit so the difference was not in the rudder iself but how yu drove the boat. Does that make sense?

 

Bob,

 

If you don't mind, I've watched guys build rudders with low drag NACA sections and I think they are crazy. Those are high lift, low drag foils, but only if you are generating lift. Otherwise, they are very fat and draggy with a lot of camber. It seems that in a well balanced boat the rudder spends a lot of time more or less streamlined in neutral, and those big fat ass cambered NACA sections would then be very draggy if they are not generating lift. Do yacht designers have a formula for the tradeoffs? Or is it more art than science? Is there anything published on this that I could look through?

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I'm no Bruce Farr and I'd love to hear his answer, but I'll answer this from my own modest experience. Yes there are trade offs, just like in keel design. You want low frontal area, low drag and low wetted surface but the foil needs to wrap around a rudder stock diameter that is usually bigger than you would like so you are limited in foil thickness. This is where carbon stocks have been a huge help. In the past the foil thickness was always a function of stock diameter on spade rudders. I use NACA foil 0012, 12% thickness at 30% of chord for all my spade rudders. In the past I have often had to go as thick as 15% to get the stock into the foil. If someone knows a better rudder foil I'd be interested in learning about it. Some design offices may have a formula for the rudder area or amount of lift they want the rudder to generate at certain angles but I have never seen one or heard of one. I do it by eye and I favor large rudders. Nobody complains when the rudder is too big. But draw one too small and your phone will ring first thing Monday morning.

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I'm no Bruce Farr and I'd love to hear his answer, but I'll answer this from my own modest experience. Yes there are trade offs, just like in keel design. You want low frontal area, low drag and low wetted surface but the foil needs to wrap around a rudder stock diameter that is usually bigger than you would like so you are limited in foil thickness. This is where carbon stocks have been a huge help. In the past the foil thickness was always a function of stock diameter on spade rudders. I use NACA foil 0012, 12% thickness at 30% of chord for all my spade rudders. In the past I have often had to go as thick as 15% to get the stock into the foil. If someone knows a better rudder foil I'd be interested in learning about it. Some design offices may have a formula for the rudder area or amount of lift they want the rudder to generate at certain angles but I have never seen one or heard of one. I do it by eye and I favor large rudders. Nobody complains when the rudder is too big. But draw one too small and your phone will ring first thing Monday morning.

 

Thank you, Maestro

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Farr does custom sections for all their rudders. In the case of say a GP IMS racer, you would assume that the crew knows what they are doing and foils will be in perfect shape. They will adjust sail trim to keep the weather helm minimal. So you can draw a low drag laminar flow (though not necessarily one with a drag bucket - and it will have the max section thickness pushed forward to help in positioning the rudder stock in the thick part of the blade). It also helps to use somewhat rectangular shaped carbon stocks so you can use a thinner section than trying to wrap a section around a tube.

 

Cruising boat shapes will be way more forgiving and these will resemble NACA 0012 shapes

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Three comments:

 

First, if possible I'll get a photo of the spade rudder modification done to Chorus, a Ketenburg-38 that is owned by Peter English. I have sailed K-38s with keel hung rudders and also sailed Chorus, it's a MUCH MUCH MUCH better boat. I know that's slightly off topic, but anyone with a keel hung rudder, who isn't in a one design like I am with my IOD, should build a spade - full stop. My feeling about skegs, having owned a number of boats that had them are similar. The skeg makes the boat sail less well for no gain. The comments about greater reliability are simply wrong and the facts at sea actually prove it, if anyone cares to gather then rather than pontificate on a board.

 

Second, if possible, try to build a rudder that will go all the way around 360 degrees. I know this sounds a little nuts, but if the rudder can't hit anything then it won't when you screw up and let go of the tiller while sailing or powering backwards. (Those of you who have a wheel are in trouble - but I don't think you should have a wheel anyway.) Moreover, when going backwards you can flip the rudder around and steer wonderfully well, particularly useful when doing a Med-tie against a mole or when anchoring. A lot of the Santa Cruz boats from the '70s and '80s do this - like the Moore-24, Olson-30, Express-27 and it is really a great trick. Those boats are small enough to scull them with the rudder, so it's great sculling backwards.

 

Finally, early in this thread folks were talking about abandoning a boat at sea because they couldn't sail home 1,000 miles without a rudder. That's simply unacceptable. If you own a boat that can't be sailed without a rudder, you need a better boat. If you don't know how to sail without using the rudder, learn. It will make you a much better sailor all around. Both my Moore-24 (an ultra light race boat) and my IOD (a 1936 designed lead mine) can be sailed on almost all points of sail without the rudder, except dead down wind. In teaching sailing I always have the kids sail their lasers around without using the rudder - it takes them 10 minutes to learn how. It is simply unacceptable to abandon one's boat because one hasn't learned how to sail without a rudder. Geeesh!

 

B

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For more than 10 years, every time my boat was in the yard at Svendsen's, Carl Schumaker would walk out from his office, put his hand on my shoulder and ask "Why does such a fast boat have such a slow rudder?". Carl and I always talked about whacking the skeg off and building a high-performance spade but then ... he died.

 

 

My boat's on the hard at the moment...never get tired of seeing Carl's foils! B)

 

This has developed into a very kuul thread! Thanks for sharing, Bob!

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Both my Moore-24 (an ultra light race boat) and my IOD (a 1936 designed lead mine) can be sailed on almost all points of sail without the rudder, except dead down wind. In teaching sailing I always have the kids sail their lasers around without using the rudder - it takes them 10 minutes to learn how. It is simply unacceptable to abandon one's boat because one hasn't learned how to sail without a rudder. Geeesh!

 

B

 

 

Howdy..

 

in the case of the laser I can see the ability to remove the rudder to prove and practice this... but have you really actually done so on the other boats you mentioned....This is where I disagree with the real viability of steering with sails..if there is absolutely nothing in the stern of the boat to facilitate tracking can it still be done?..my gut tells me yest you can sail but not where you may want to go..by that I mean if you miss an Island by 500 miles its not much help right? even if your going in say the general direction.

 

I just dont believe it will be anything close to the same experience IMHO

 

My gut has been wrong on many occasions though so again I have no experience to draw on here..OK

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Are we talking about the same thing, a rudder that is completely gone versus one that there but is inoperable?

 

Aren't some of these rudder-rescue problems related to the fact that the rudder was not just inoperable, but completely MIA?

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Both my Moore-24 (an ultra light race boat) and my IOD (a 1936 designed lead mine) can be sailed on almost all points of sail without the rudder, except dead down wind.

 

You sailed these boats with the rudders on the boat, but not using them?

 

Or did you sail these boats with no rudder affixed to the boat at all?

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Both my Moore-24 (an ultra light race boat) and my IOD (a 1936 designed lead mine) can be sailed on almost all points of sail without the rudder, except dead down wind.

 

You sailed these boats with the rudders on the boat, but not using them?

 

Or did you sail these boats with no rudder affixed to the boat at all?

 

 

In the case of the Moore-24 and the IOD the tiller was free to wander but the rudder was in place. In the case of the Laser and 420, when I'm teaching kids to sail, I take the rudder off all together and put it in the chase boat. They kids, within minutes, figure out how to gybe, tack and sail on every point of sail. Just as I can do with my larger boats, but I haven't really tried it without a rudder all together.

 

I don't think there is much difference at all between no rudder and a free-to-move rudder. BobP might weigh in here. It takes very little effort to turn either boat's rudder so there isn't any lateral stability being provided by it, I don't think. If the stern wants to go sideways, the rudder turns and the boat's stern goes sideways. Note, the tiller is NOT tied down - that's a way of sailing with out a self steering gear, but not what we're talking about.

 

The trick to sailing this way is control of the angle of heel and what sails you have up. For example, on the Moore, you must reef the main, even in light winds, if you want to sail downwind without the rudder. There's just too much pressure turning the boat into the wind if you don't. You also have to wing out the jib sometimes. On a laser you do this by heeling the boat to windward to keep it from turning up wind, but the Moore is too heavy for this - or I'm not heavy enough. There are times when I have to sail downwind with only the chute up, or only a headsail, to accomplish this. But, there has never been a time when I couldn't go anywhere and would consider giving up my boat.

 

The only time I could consider giving up is if the rudder were jammed and there was no way to get rid of the thing at all. But, that's pretty darned unlikely. You can always cut things off a boat and let 'em sink.

 

I'm happy to provide more details on how it's done if anyone's interested, but it's pretty well described in most dingy sailing books. BTW, I'd strongly suggest that anyone who really wants to go long distance cruising should spend a lot of time in a nice conservative two person dingy like a 420. If you can do what the High School kids do, you'll be a much better sailor than most I've run across out there cruising.

 

B

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Both my Moore-24 (an ultra light race boat) and my IOD (a 1936 designed lead mine) can be sailed on almost all points of sail without the rudder, except dead down wind.

 

You sailed these boats with the rudders on the boat, but not using them?

 

Or did you sail these boats with no rudder affixed to the boat at all?

 

[...]

The trick to sailing this way is control of the angle of heel and what sails you have up. For example, on the Moore, you must reef the main, even in light winds, if you want to sail downwind without the rudder. There's just too much pressure turning the boat into the wind if you don't. You also have to wing out the jib sometimes. On a laser you do this by heeling the boat to windward to keep it from turning up wind, but the Moore is too heavy for this - or I'm not heavy enough. There are times when I have to sail downwind with only the chute up, or only a headsail, to accomplish this. But, there has never been a time when I couldn't go anywhere and would consider giving up my boat.

 

The only time I could consider giving up is if the rudder were jammed and there was no way to get rid of the thing at all. But, that's pretty darned unlikely. You can always cut things off a boat and let 'em sink.

 

I'm happy to provide more details on how it's done if anyone's interested, but it's pretty well described in most dingy sailing books. BTW, I'd strongly suggest that anyone who really wants to go long distance cruising should spend a lot of time in a nice conservative two person dingy like a 420. If you can do what the High School kids do, you'll be a much better sailor than most I've run across out there cruising.

 

B

 

No offense intended, and I'm not defending the people who abandon ship without even attempting to jury-rig some method of steering, but have you done this "steering by heeling" trick on a heavier boat, in big seas and strong winds? What works on a dinghy in flat water may not be adequate in other circumstances. As for cutting away a damaged rudder, I know for sure I wouldn't want to be diving under my boat in big seas with nothing but a hacksaw and a lungfull of air.

 

But I've never had to deal with any of this, other than practicing in benign conditions, so what do I know anyway???

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Finally, early in this thread folks were talking about abandoning a boat at sea because they couldn't sail home 1,000 miles without a rudder. That's simply unacceptable. If you own a boat that can't be sailed without a rudder, you need a better boat. If you don't know how to sail without using the rudder, learn. It will make you a much better sailor all around. Both my Moore-24 (an ultra light race boat) and my IOD (a 1936 designed lead mine) can be sailed on almost all points of sail without the rudder, except dead down wind. In teaching sailing I always have the kids sail their lasers around without using the rudder - it takes them 10 minutes to learn how. It is simply unacceptable to abandon one's boat because one hasn't learned how to sail without a rudder. Geeesh!

 

B

 

 

the problem is the waves..., in the middle of the ocean, they can be pretty big.

 

without a rudder, you are basically limited to some sort of downwind course. once the waves get big - say ~12ft and up, it can be a lot of work to steer downwind, even with the rudder! The winds might be 20-30, and there is basically no way you are go steer without a really good emergency rudder. 90% of boats on the ocean don't have one.

 

It's absolutely nothing like sailing a dinghy, or even a small keel boat, without the rudder in protected waters with smaller waves.

 

The problem is that as the waves get bigger and bigger, you won't be able to stop the boat from turning broadside - this can happen even with a rudder - and - if the waves are big enough, the boat will roll, and you will loose the mast..., and so on.

 

If the boat is going broadside to waves, on the open ocean, you are in a _very_ dangerous situation when the inevitable storm comes up.

 

Most people will get off on the first passing freighter, rather than risk the lives of their family or crew. That's probably what I would do.

 

the people who abandon these boats aren't idiots..., they are faced with a very difficult situation - they've lost their rudder, have maybe a few thousand miles to go, at maybe 4kts, they have a boat that they can't steer safely in big seas, and they may not get another chance to get off. I've done a few ocean crossings, and it's not like there are lot's of freighters out there waiting to pick you up.

 

when faced with risking lives of friends or loved ones for a big hunk of plastic, most people will opt to save the lives.

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Finally, early in this thread folks were talking about abandoning a boat at sea because they couldn't sail home 1,000 miles without a rudder. That's simply unacceptable. If you own a boat that can't be sailed without a rudder, you need a better boat. If you don't know how to sail without using the rudder, learn. It will make you a much better sailor all around. Both my Moore-24 (an ultra light race boat) and my IOD (a 1936 designed lead mine) can be sailed on almost all points of sail without the rudder, except dead down wind. In teaching sailing I always have the kids sail their lasers around without using the rudder - it takes them 10 minutes to learn how. It is simply unacceptable to abandon one's boat because one hasn't learned how to sail without a rudder. Geeesh!

 

B

 

 

the problem is the waves..., in the middle of the ocean, they can be pretty big.

 

without a rudder, you are basically limited to some sort of downwind course. once the waves get big - say ~12ft and up, it can be a lot of work to steer downwind, even with the rudder! The winds might be 20-30, and there is basically no way you are go steer without a really good emergency rudder. 90% of boats on the ocean don't have one.

 

It's absolutely nothing like sailing a dinghy, or even a small keel boat, without the rudder in protected waters with smaller waves.

 

The problem is that as the waves get bigger and bigger, you won't be able to stop the boat from turning broadside - this can happen even with a rudder - and - if the waves are big enough, the boat will roll, and you will loose the mast..., and so on.

 

If the boat is going broadside to waves, on the open ocean, you are in a _very_ dangerous situation when the inevitable storm comes up.

 

Most people will get off on the first passing freighter, rather than risk the lives of their family or crew. That's probably what I would do.

 

the people who abandon these boats aren't idiots..., they are faced with a very difficult situation - they've lost their rudder, have maybe a few thousand miles to go, at maybe 4kts, they have a boat that they can't steer safely in big seas, and they may not get another chance to get off. I've done a few ocean crossings, and it's not like there are lot's of freighters out there waiting to pick you up.

 

when faced with risking lives of friends or loved ones for a big hunk of plastic, most people will opt to save the lives.

 

 

Look, I'm not claiming that the folks who abandoned their boats are idiots - not at all. They have a certain set of skills and they were the one there, not me. They made their decision and it's theirs to make. I was simply expressing what I probably would or wouldn't do.

 

As to waves, I'm VERY well acquainted with large waves and the effect they have on boats. In my humble opinion, if a boat is actually At Risk in 12 foot waves, it has no business being out cruising around. There are LOTS of places that regularly get twenty foot waves or more. Look, I live in San Francisco, have sailed to Panama and back and to New Zealand and back. I've cruised all over the place and raced in gigantic waves. Indeed, there are plenty of times when the waves reach over 12 feet on a spring series race here around the Farallons, it's not considered dangerous at all. Once, traveling from Samoa to Tonga, I spent three days aboard a Wylie-65 with 30 to 40 foot and winds of 60 knots plus. 'Nuff said, I know what waves do to a boat.

 

Now, as to sailing a boat without a rudder in waves. There certainly will be times when the boat changes course, and if it's really a boat that is poorly designed enough to capsize and loose the rig on a 12 foot, or even a 20 foot wave, then you shouldn't be aboard it. (A lot of boats are built that you shouldn't be aboard IMHO.) However, there are also a lot of boats that are just fine in really big waves without a rudder. The Moore is perfectly happy sailing her self down wind with a headsail up in 35 knots and 20 foot seas. I did a while back coming back from Drakes Bay in April during a big blow. I was tired, I don't have an autopilot, so I just put up the #3 and let her sail along on a broad reach. She was fine. She's a 2000 pound ULDB sloop, 24 feet long. Similarly, I've done the same thing on a Wylie-65, Kettenburg-50 and a Cal-40. The waves do turn the boat a bit, but it's no where near as violent as you're imagining. Of course, if you're trying to steer to a course and hold it within 5 degrees, you'll be using the rudder a lot. But, try not steering and watch what happens - especially if you do NOT have the main up. It's a piece of cake. Try it, just leave the mainsail down.

 

On the question of boats that will not do this, I would include any of the boats with extremely wide sterns (typically the ones with two double berths aft) and shallow keels. There are a lot of these used in the charter business, and those boats are simply not safe in large waves generally. I'm not going to name names. But, you all know that there are lots of boats that will nearly tack themselves in a puff, can't hold a course on a reach, and are terribly hard to sail in high winds. Those are NOT good cruising boats, and I personally won't set foot aboard them anymore.

 

With respect to cutting away a rudder. I haven't done that. But, twice I've had the rudder simply disappear. Once was a soling, during a regatta. That was fun - 50 boats around and no way to steer. It fell off. The other was a Jeaneau in Tonga where the thing just dropped out the bottom. I don't think it would be possible to cut away a rudder with a lower bearing like a skeg or a traditional stern hung rudder. But, a spade rudder is actually easier to get rid of. You take the tiller off and drive the thing down through the boat with an oar or something long and slender. It's how we get the rudders out of boats when we want to work on them. In high seas, sure it'd be hard. But, you've got a lot of time, you're not going anywhere.

 

Over the years I've fixed all sorts of things, from cracks in hulls, parted shrouds, broken prop shafts, to broken masthead sheeves. It's hard in a storm, so some times you wait three days or a week for the wind and sea to die down and then you go fix it. So long as there isn't any real chance of the boat sinking, it's just uncomfortable, not dangerous. I have had people get pretty upset when they realize that they'll be rolling around in their berth for three or four days, just waiting for the storm to blow itself out.

 

I am sure that many people are really afraid of rolling over. But, there are really very few boats that will actually do this if the waves aren't really breaking. I am also sure that most folks don't want to learn if their boats are the sort that roll over while they're in a storm. This is the reason that it's important to have a really good naval architect design your boat and to know what it's point of zero stability is. How far will it tip before it goes all the way over?? Beamy boats are comfortable in harbor but at sea, they like to float upside down almost as much as right side up. BobP can help with what's an acceptable point of zero stability, but I like it really really big. You can google "Point of Zero Stability" or go here for some interesting reading on this topic at:

 

http://books.google.com/books?id=GliCdk2ex...result#PPT98,M1

 

I've blathered on long enough. Again, I wasn't calling anyone and idiot. I would say, however, that more experience (particularly in selecting a boat that is truly seaworth) would have probably lead them to stick with the boat and sail it home.

 

B

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Bob,

 

If you don't mind, I've watched guys build rudders with low drag NACA sections and I think they are crazy. Those are high lift, low drag foils, but only if you are generating lift. Otherwise, they are very fat and draggy with a lot of camber. It seems that in a well balanced boat the rudder spends a lot of time more or less streamlined in neutral, and those big fat ass cambered NACA sections would then be very draggy if they are not generating lift. Do yacht designers have a formula for the tradeoffs? Or is it more art than science? Is there anything published on this that I could look through?

Low drag (laminar flow) sections have low profile drag while in the drag bucket and operating at the Re that suits them. It makes no difference if they are generating lift. In fact if the are operating at too high a lift coefficient most of them are out of their low drag bucket. They look fat because the pressure gradients required to achieve laminar flow requires a certain profile. The thickness is generally determined by structural and stall considerations and will be nearly the same whether the section is laminar flow or not.

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Here's an interesting little rudder story . I was talking to a cruiser a couple of years ago and he was telling me about bringing a boat ( a south pacific 42? I don't know American boats too well) back from the US to here ,NZ. Out of Fiji on passage here they lost the skeg off the boat... noticed that the rudder was flexing and bad noises etc . On diving they discovered that the whole skeg had just dropped off... said something about it being bolted on and those bolts had sheared ,crevice corrosion or whatever.

Anyway, the bit I found interesting was that they had to drop the rudder out ( it couldn't live there ) which they did ,but no matter what configuration they came up with for jury steerage ,they just couldn't get the boat to steer. Thats because the skeg was part of the lateral plane and without it , the boat just kept rounding up.

Fortunately they were cruising with another boat so they towed it with all their chain etc out as the tow warp and sails set. That held the bow on course and they tow sailed it something like 400 odd miles back here( or was it from 400 out of Fiji) Long way anyway.

 

 

 

far out, I didn't write any of that in my profile. Not that I mind,,, I just didn't do it.

 

Been racking my less than it used to be brain for what type of boat this actually was and chatting to some mates over a rum the other day we think it was actually a Gulfstar.... maybe bigger at 44? We recall a Florida link ( is that where they were built?) and it had a centre cockpit with a massive closed in dodger/ bimini thing with clears all around.

Why I thought it was a South Pacific 42.. not sure maybe just association after reading Bobs book recently? or the fact we've been talking about one thats for sale here recently.( looks like a steal)

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Owen:

All spade rudders are not created equal. Your skeg hung rudder probably was limited to 30 to 40 degrees each side of centerline. Your spade did not have that limit so the difference was not in the rudder iself but how yu drove the boat. Does that make sense?

 

Bob,

 

My spade rudder is not quite that constrained; it can travel 45 deg. off centerline. And yes, the spade rudder does have a wider range of motion available, but in operation we never use much more than 45 deg. of deflection. But the spade can quite easily be made to totally stall, at which point it becomes completely useless. On the other hand, I have never been able to get the skeg-hung rudder to stall at all, no matter how quickly and fully I fling it over. Perhaps those few extra degrees of attack angle make all the difference and the skeg is not really involved.

 

Is John Vigor disagreeing with you here?

 

"A skeg-hung rudder will not stall as readily as a spade rudder, and tends to hold a stedier course because it will center itself when left alone, rather than take a small "lead" to port or starboard as a semibalanced spade rudder will do." -- p. 277, The Practical Encyclopedia of Boating (2004)

 

Owen

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Dear Valued Hunter 450/456/460/466/46 Owner:

Seasoned offshore sailors understand and appreciate the fact that rudders are designed and

manufactured to protect the hull of the boat from serious under-water damage. Over the past several

years, we have received reports from some owners who have inadvertently lost their fiberglass

composite post rudders during boating activity. Our goal with this communication is to explain how this

loss might occur and to provide you with recommendations for enhanced maintenance options, plus

encourage ongoing safety education for captain and crew alike in the case of rudder loss.

 

By virtue of its design, whenever a boat runs aground, or when the rudder strikes or is struck by an

object, there is always a chance that the rudder post has been compromised or weakened to some

extent. This weakening may go undetected, and may only become evident after continued or extensive

use, possibly in adverse conditions.

 

While Hunter Marine’s limited warranty specifically does not warrant the rudder because of the

significant linkage to boat operation, it has always been Hunter Marine’s policy to examine rudder

stocks where there has been a rudder loss, whenever possible. Our goal in analyzing rudder loss is to

determine cause and continually seek methods of improvement in our approach to design and

manufacturing.

 

Specifically, Hunter Marine is aware of 16 rudders which have been lost on boats within your size

range, most of which had been in use for more than two years. We were able to review 13 of the

16 reported. Our research indicates that 11 were well within the design and manufacturing

tolerances. One rudder post may have had a manufacturing problem, while another was within the

design tolerance but did not meet Hunter’s internal tolerance specifications.

 

http://www.huntermarine.com/SafetyTuneUp/H...r2007TuneUp.pdf

 

The concern about spade rudders is no idle concern. If I understand Hunter correctly, most of these rudder failures were within their parameters and nothing was wrong with the rudder, other than the fact that they failed.

 

Further, I think in their first sentence above they said that the rudder is designed to fail in order to save the hull from damage. I know at one time Bruce Roberts, the steel boat designer, was advocating a similar design approach.

 

No, that is why some of us would never buy a Hunter.

pos engineering

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