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25-09-2018, 15:50
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#16
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Writing Full-Time Since 2014
Join Date: Nov 2008
Location: Deale, MD
Boat: PDQ Altair, 32/34
Posts: 9,569
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Re: Manufactured Emergency Rudders - are you in need of it?
Quote:
Originally Posted by Uplander
Sounds interesting Thinwater. Do you have a photo or sketch?
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The rigging goes something like this:
As Seabrake drogue looks like this. I've tested most brands. You can steer pretty well off the wind or motoring. Upwind is pretty limited, as you might guess, but you can sail up to about 70 degrees true wind; you just need to balance sails and pull the drogue in close to reduce drag.
A rudder is better.
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25-09-2018, 22:30
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#17
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Registered User
Join Date: Jul 2014
Location: Hawaii
Boat: Jeanneau SO DS 49
Posts: 356
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Re: Manufactured Emergency Rudders - are you in need of it?
Anchors will work, as will fenders, buckets, drouges, docklines, heads, etc.
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26-09-2018, 01:30
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#18
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Registered User
Join Date: Sep 2013
Posts: 104
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Re: Manufactured Emergency Rudders - are you in need of it?
Possible loss of my spade rudder was a major reason for buying a Hydrovane wind vane for self steering. I think anyone going Bluewater needs backup steering esp with unprotected rudders. There is a definite need for an emergency rudder for cruising yachts but it has to be very strong and suitable for a wide range of sizes and transom configurations. Difficult to achieve at a cost point that would make it widely attractive. However good luck with the project.
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26-09-2018, 03:20
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#19
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Registered User
Join Date: Jan 2017
Location: Narragansett Bay, RI
Boat: Beneteau Oceanis 523 (2005)
Posts: 117
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Re: Manufactured Emergency Rudders - are you in need of it?
Just received my Scanmar emergency rudder/tiller last week (not mounted yet). Lots of detailed measurements of transom in advance so they could custom bend the stainless to allow me to attach mounts to the transom.
For price to come down, which is a requirement to hit any sizable market, seems to me the custom manufacturing step must be eliminated.
Get the design right and perhaps some boat builders will consider an emergency rudder a superior alternative to an emergency tiller? If the USCG/ABYC would allow that replacement?? Could be a marketing benefit if cost right - but likely only for those boats marketed as blue water (doubt Beneteau, for example, wants to promote how they have a superior way to handle losing your rudder!)
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27-09-2018, 06:11
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#20
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Registered User
Join Date: Mar 2010
Location: Annapolis MD
Boat: Building a Max Cruise 44 hybrid electric cat
Posts: 3,194
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Re: Manufactured Emergency Rudders - are you in need of it?
Here is our emergency rudder set-up on our old Sabre. I ended up laminating a rudder blade and cassette, but never tried it out. We could have bolted together plywood from the boat's doors or something if I didn't have an actual rudder blade on board. The three mounts were permanently bolted to the transom and the triangle mount was stored below unless on passage when it was mounted before leaving.
Matt
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27-09-2018, 06:31
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#21
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Registered User
Join Date: Sep 2008
Location: On the boat, somewhere in Australia.
Boat: Swanson 42 & Kelly Peterson 44
Posts: 9,126
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Re: Manufactured Emergency Rudders - are you in need of it?
Quote:
Originally Posted by Paul L
A well executed design for a reasonable price would have a market. A couple of requirements:
1. mountable in rough conditions. Some sort of cassette slot, instead of pintles.
2. multiple sizes for boats say 28 to 46ft.
3. light weight
4. easy break down, easy storage
5. flexible tiller routing for different sterns
6. minimal holes in yacht for mounting hardware.
Not an easy design criteria
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Everything Paul said... but add a trim tab so that it can double as a windvane steering system.
__________________
Refitting… again.
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27-09-2018, 10:21
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#22
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֍֎֍֎֍֎֍֎֍֎
Join Date: Apr 2006
Posts: 15,136
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Re: Manufactured Emergency Rudders - are you in need of it?
"1. mountable in rough conditions."
Which makes any pintle or cassette on the transom approach a non-starter. While Matt's fixture certainly looks like a robust and reasonable design, what happens if you are on a 34' boat, where you might want five feet of rudder clear below the waterline, and that's four or five feet "down" from the pushpit or rear lifeline?
You've got to fight something like eight feet of lever arm, getting the weight out and down and positioned, and hopefully there will be a mechanism to lock it into position, so you don't have to hang upside down to tighten bolts. Now do this again in moderate ocean conditions, four foot waves to eight foot waves. Bearing in mind that heavier seas and winds are often what break rudders.
The steering board was used by the Vikings to cross oceans. It has worked for a couple of thousand years. Bulky, yes. Cumbersome, yes. Autopilot friendly, no. Easy to stow, no. But I think that for a highly effective emergency rudder, an old style steering board still has merit. I know that used to be recommended by many of the cruising authors pre-internet, often around the concept of making up the board and attachments and using a spinnaker pole or other spar specifically for that purpose if needed.
Pole cost? Free, if it is on the boat. Balance of cost? A hundred bucks for a heavy piece of plywood and some u-bolts? Not elegant, but that's basically what steered Kon-Tiki, too.
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27-09-2018, 12:56
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#23
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Registered User
Join Date: Jul 2005
Location: Bellingham
Boat: Outbound 44
Posts: 9,319
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Re: Manufactured Emergency Rudders - are you in need of it?
A cassette style mount can be used in rough conditions. It doesn't require the precise alignment of a pintle.
To be practical for many boats the emergency rudder has to be storage friendly.
__________________
Paul
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27-09-2018, 13:19
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#24
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Writing Full-Time Since 2014
Join Date: Nov 2008
Location: Deale, MD
Boat: PDQ Altair, 32/34
Posts: 9,569
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Re: Manufactured Emergency Rudders - are you in need of it?
Interesting thread. I'm not trying to solve anything, only to interject two thoughts:
- Stabilize the boat first with a drogue. They make a HUGE difference when trying to work; a slow down wind drift vs. lying ahull, rolling and bucking unpredictably. Additionally, for those of you that have never been on a boat with no rudder, simply missing that aft lateral plane make the motion just insane. Deploy a drogue, even if only to stabilize the boat while you work. It really helps.
- I'm not sure heavy weather gets most rudders. Flotsam is far more likely and the weather is generally reasonable... though probably with enough wind that you were sailing fast.
- If it was really heavy weather, you may want to set the drogue and wait a day. Unless there is a lee shore, someone could get hurt frogging around. If there are waves hitting the emergency rudder while you are installing it, this is not going to work, no matter how elegant the design. Remember, waves broke the first one!!
So I would still argue you should either have some manner of drogue or have practiced deploying a good makeshift drogue. Not just warps; that is not NEARLY enough force with the rudder gone.
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27-09-2018, 13:22
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#25
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Marine Service Provider
Join Date: Sep 2011
Location: California
Boat: Alerion Express 38 Yawl (former)
Posts: 468
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Re: Manufactured Emergency Rudders - are you in need of it?
I've had to prepare a number of boats for Category 1 racing, and figuring out the emergency steering solution has been one of the biggest challenges of that effort. Despite my work on finding solutions, I was never sure that my rudder designs would last the required distance to a safe port, nor would they steer the boat in all conditions.
I think Jim Antrim, NA, has done a lot of good work on e-rudder designs. You may want to look at his website for his ideas. Several themes seem to be common to all designs: - Small surface area so it doesn't create enormous forces.
- Enough depth of immersion so it doesn't ventilate.
- It has to be able to be steered, despite the pushpit, backstay, running backstays, GPS antenna, davits, etc.
- It has to be able to be shipped at sea, even if the boat is out of control at the time.
- A vertical axis so you're not trying to lift the stern or depress the stern when you steer.
I did see a proposed design of a carbon fiber e-rudder at the boat show in Richmond, CA about two years ago. Interesting, versatile design, and quite light. I don't know what happened to the company.
If race organizing authorities were more demanding in what they would accept for an e-rudder, you'd have a better chance of selling them...
Chuck Hawley
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27-09-2018, 13:44
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#26
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Moderator
Join Date: Aug 2009
Location: Solent, England
Boat: Moody 31
Posts: 18,423
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Re: Manufactured Emergency Rudders - are you in need of it?
Quote:
Originally Posted by hellosailor
Pole cost? Free, if it is on the boat. Balance of cost? A hundred bucks for a heavy piece of plywood and some u-bolts? Not elegant, but that's basically what steered Kon-Tiki, too.
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I thought this was quite a clever variation on the pole theme which I haven't seen before. We have a transom step probably just the right place for the pole to attach if it will fit. Need to check next time I am down the boat.
Interesting article backing up Thinwaters posts about a drogue.
https://www.pbo.co.uk/gear/which-dro...-you-buy-25543
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27-09-2018, 14:10
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#27
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Writing Full-Time Since 2014
Join Date: Nov 2008
Location: Deale, MD
Boat: PDQ Altair, 32/34
Posts: 9,569
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Re: Manufactured Emergency Rudders - are you in need of it?
Common sense, and to add to Chuck's comments...
When steering with a drogue or emergency rudder, you adjust the sail plan for balance. This might mean striking the main, reefing earlier, and trimming more for balance than power.
Also, a jammed rudder is different from a missing rudder. In the first case it is fighting you. In the second case the back of the boat is all swirly because of no lateral plane. The latter issue makes me wonder if a fixed blade, just for stability, might allow the rudder to be much smaller. I'm pretty sure this is true.
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27-09-2018, 15:02
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#28
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Registered User
Join Date: Dec 2012
Location: New Orleans
Boat: Bruce Roberts 44 Ofshore
Posts: 2,842
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Re: Manufactured Emergency Rudders - are you in need of it?
You guys are making this more complicated than it needs to be. Make yourself a sweep oar. On a bigger boat it might have to be very long. On a small boat, maybe only 10' to 12'. A blade with a socket on it that you could pin onto a whisker pole might work. Anyway just lash it between the stern cleats or other hardware. Rig a handy billy for steering if required. You would be surprised how well this works. It's how the Vikings steered and it worked well enough for them, apparently, on bigger boats than the typical sailboat today.
__________________
GrowleyMonster
1979 Bruce Roberts Offshore 44, BRUTE FORCE
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27-09-2018, 15:25
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#29
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Registered User
Join Date: Jul 2012
Location: Hobart
Boat: Alloy Peterson 40
Posts: 3,919
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Re: Manufactured Emergency Rudders - are you in need of it?
I really like the look of the soft sail type emergency rudder systems. They are compact, light, cheap to produce and distribute, and I don't think anyone is making them commercially. Designed cleverly they could also double as a riding sail, storm jib, fothering sail and man overboard recovery system.
The sail would probably need full length battens, and a system of brackets or lashings to support the struts somehow.
Prehaps a trim tab could be used to rotate the soft rudder/sail. Other random thoughts are using an upside down A frame support system, and twin rudder sails on the A frame struts. Or even twin rudders on a ladder style girder like a biplane rig for bigger boats.
Soft Emergency Rudder
http://sfbaysss.org/resource/doc/kam...ncy-rudder.pdf
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05-10-2018, 23:41
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#30
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Registered User
Join Date: Oct 2013
Location: Fremantle, Western Australia
Posts: 77
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Re: Manufactured Emergency Rudders - are you in need of it?
To the student team:Commercial adaptable solution already exists in Western Australia (not owned by me). Contact me for details.
Kim Klaka
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