A modern take on the Yuloh / Sculling Oar - Would you be interested?

[GrowleyMonster]

A sculling oar or yuloh or similar device is not very efficient. Conventional rowing is much more efficient. The advantage of over the stern sculling type oars is you can maneuver in narrow passages between boats or piers or banks or retaining walls. Thats why the Venice gondoliers use them. Some of the canals can be kind of narrow and there is opposing traffic to deal with. Another advantage of an over the transom oar is it can be used just for steering, in an emergency. But I would hate to have to stem even a gentle current or wind with a sculling oar in a cruising sailboat. I think I would rather find a good spot to anchor, and wait for favorable wind or tide. Or beg for a tow. With regular oars I would maybe give it a go, if the transit were a short one. In fact, one of my upcoming projects is a pair of custom oars for GF's 20' Halman and maybe a pair for the Cal 2-27. And the oars will be long enough to use one as an emergency sweep, too.

[Pete7]

Originally Posted by SuW

I don't intend to sound whiny. It still beats doing almost anything else!

Same here, we burn 90 litres of fuel a year on average. Our favourite cruising grounds are 120 miles to windward. The strong tides really help but but after a long day and if a tide that has turned I don't have a problem turning the engine on and finishing off the trip or using it to ensure we catch a tidal gate. It also gives us hot water which we have no other way of generating.

We met a solo Dutch guy who had spent the whole summer sailing up and down the English Channel and clearly very happy with life. He sailed a little wooden 26ft yacht. Trapped in a harbour surrounded by other similar sized yachts we spent half an hour moving boats and ropes so he could leave. I was astonished when he cast off and pushed out into the harbour without even starting the engine. He then flicked a switch and turn a dial, next his yacht moved forward. He had an electric motor installation. However, with just a couple of small solar panels I guess it was for close quarter docking use only. Nice to be able to have the time to sit and wait for the conditions to change and suit your next move.

Some years ago I spent a weekend driving my rib acting as a safety boat for a group of novice ocean rowers. Given their 21ft boats are purposely designed to be rowed with long oars one person could average about 2 knots at sea. If I ever have to row I will use the dinghy and tow the yacht but it won't be further than across a small harbour.

[SuW]

Originally Posted by Pete7

We met a solo Dutch guy who had spent the whole summer sailing up and down the English Channel and clearly very happy with life...Nice to be able to have the time to sit and wait for the conditions to change and suit your next move.

What a great story! Sounds like a modern-day £200 millionaire!

Originally Posted by Pete7

Some years ago I spent a weekend driving my rib acting as a safety boat for a group of novice ocean rowers. Given their 21ft boats are purposely designed to be rowed with long oars one person could average about 2 knots at sea. If I ever have to row I will use the dinghy and tow the yacht but it won't be further than across a small harbour.

It's not just the long oars - most fast rowing boats have, as well a long waterline, a sliding seat and fixed foot stop which allows the big muscles of the legs (and buttocks, back and stomach) to be used to propel the boat. I think the records are about 6 knots for single rowers in flat water. I didn't discover this kind of rowing until I was 53 but it is a great all body workout and you can keep doing it into extreme old age...

There was an article in Cruising World magazine many years ago about a lady who had set up a sliding seat rig in her cruising boat's 8-10 foot hardshell dingy (I think using a Piantedosi drop-in unit). Of course, that and the longer oars are pretty pricey...

[john61ct]

Crew shell as dinghy, I love it.

[SuW]

Originally Posted by john61ct

Crew shell as dinghy, I love it.

I admit the idea has some drawbacks in practical terms, for example, pulling up alongside the mother ship and not being able to get the oars/oarlocks out of the way without falling in. You're still 3m away...

[Don C L]

Well, as I have reported with my experiences with my oars, they are another option, as a yuloh would be for those boats with a low enough freeboard onthe transom and a good place to stand, and a good place to stow the yuloh. For river boats the issue of stowage is moot since the yuloh probably lives back on its mount/oarlock. As far as oars being in the way, I can ship mine easily and quickly, and can continue with one oar on one side if needed, as a gondola is usually propelled. BUT I'll be the first to admit I am not going too fast. With one oar, and steering the tiller with my legs, it's doable, and in fact sometimes I actually prefer it for comfort.. it just seems easier to wrestle one oar in two hands when moving a heavy mass.. as with a gondola or a yuloh

https://www.youtube.com/watch?v=NFlqqoSmi9k

The yuloh's thrust is more continuous than oars since it is providing propulsion on both the pull and push. And I am no engineer, but I suspect it is not as inefficient as it may seem, but I'd sure like to see someone do the math. And then there is the shape of the blade. It may seem intuitively that a short wide blade would be best, but if you search for sculling oars and rowing oars, many folks prefer a longer narrower blade. In fact, my whitewater rafting oars have a fairly wide short blade and I would prefer the longer narrower blades I have on my dory (but can't find (or afford) the longer ones I'd need from a nearby source) When I set my blades in, being so wide they get a big bite. Now that would be fine if I were going fast in a shell, but for getting a heavy mass moving I'd rather have the narrower blade that can be dragged through the water on the pull while the boat is slowly getting its mass moving, if that makes sense.
BTW, have you all seen this page on Atomvoyages? He has a brief discussion of sculling and rowing and a shot of his sculling oar.
Atom Voyages - Cruising FAQ

[Sparx]

Responding to the original post ...

I have used a yuloh with some success on a 20 foot sailboat. The yuloh propelled the boat gracefully at maybe 2 to 3 knots, and with some technique I found I could keep this up for extended periods of time. The yukoh was an enjoyable method for moving the boat when there was insufficient wind, and much less tiring than rowing.

The yuloh was built from a combination of my engineering and wood working skills. I made several prototypes to resolve engineering details. Perhaps you could do some modeling to optimize the yuloh geometry. I suggest also modeling the yuloh for a variety of boat mass and transom heights to find sweet spot combinations. Then design yuloh models using these sweet spots for boats in your target range.

In my experience the yuloh ends up being a significant fraction of the boat length. Figuring out how to store a yuloh is part of the solution. I would strongly prefer a one piece yuloh for robustness and convenient deployment without much fuss. See what you can do with that boundary condition.

It is tempting to imagine a strong lightweight yuloh made of carbon fiber. However I encourage you to experiment with yuloh weight as it seems that some mass in the yuloh makes for smoother operation, a better human interface.

Given that the yuloh performance seems to be highly dependent on being matched to the specific parameters of an individual boat it might be worth considering connecting a modeling algorithm to a 3d printer to efficiently produce yulohs custom fitted to individual boats.

As you can see from prior comments there will be marketing challenges to selling yulohs. However your concept makes a reasonable engineering project that might fill a niche in the boating world.

I found the yuloh very asthetically pleasing to use. It was great to not be dependent on energy sources other than the wind and my own strength.

PM me if you would like to discuss further.

[Don C L]

Originally Posted by Sparx

Responding to the original post ...

I have used a yuloh with some success on a 20 foot sailboat. The yuloh propelled the boat gracefully at maybe 2 to 3 knots, and with some technique I found I could keep this up for extended periods of time. The yukoh was an enjoyable method for moving the boat when there was insufficient wind, and much less tiring than rowing.

The yuloh was built from a combination of my engineering and wood working skills. I made several prototypes to resolve engineering details. Perhaps you could do some modeling to optimize the yuloh geometry. I suggest also modeling the yuloh for a variety of boat mass and transom heights to find sweet spot combinations. Then design yuloh models using these sweet spots for boats in your target range.

In my experience the yuloh ends up being a significant fraction of the boat length. Figuring out how to store a yuloh is part of the solution. I would strongly prefer a one piece yuloh for robustness and convenient deployment without much fuss. See what you can do with that boundary condition.

It is tempting to imagine a strong lightweight yuloh made of carbon fiber. However I encourage you to experiment with yuloh weight as it seems that some mass in the yuloh makes for smoother operation, a better human interface.

Given that the yuloh performance seems to be highly dependent on being matched to the specific parameters of an individual boat it might be worth considering connecting a modeling algorithm to a 3d printer to efficiently produce yulohs custom fitted to individual boats.

As you can see from prior comments there will be marketing challenges to selling yulohs. However your concept makes a reasonable engineering project that might fill a niche in the boating world.

I found the yuloh very asthetically pleasing to use. It was great to not be dependent on energy sources other than the wind and my own strength.

PM me if you would like to discuss further.

Don't hold us in suspense! Got any photos of your set-up? (For the 4 or 5 of us who entertain such crazy notions!)

[Sparx]

Don, thanks for asking. I am afraid I don't have any photos. I used the yuloh for several years more than a decade ago.

My prototypes were a framing lumber 2x4 with an angles cut for mounting the blade, which could be a 1x6 or a piece of plywood. After trying several blade geometries I went with a long and narrow blade with curved forward face hand carved from a 10 or 12 foot length of 1x6 ash as I recall. The handle was laminated from cedar and ash strips into a pleasant and useful curve. The total yuloh length was around 16 feet.

The key to the yuloh, and what makes it different from a scull oar is the line running from handle to deck in front of the user. This line bears the weight of the yuloh and much of the propelling force. The yuloh woyld be quite tiring without this.

Here is some info to get started on design considerations

http://junkrigassociation.org/Resour...efficiency.pdf

[pcmm]

Originally Posted by Don C L

Oh I don't know, when you see those videos of folks sculling sampans around in southeast Asian ports... they don't look too burly

A sculling oar doesn't require a lot of strength to operate, just enough to push it side to side. The secret is in the lanyard. Attach a line from the handle of the oar and run is vertically down to a point on deck/cockpit. Now all you need to focus on is tilt and pull, then tilt and push. the lanyard does the work of controlling the vertical position of the handle.

[Breffni]

Everything is possible, even your request which I really appreciate !!
https://www.shawandtenney.com/produc...SAAEgK3zvD_BwE

[arcticmonkey]

Hate getting piqued in the morning
What the heck.... Yuloh... found page ... geocities.ws/nelstromlinson/boat/sculls.and yulohs... wow ! interesting

[Ken Sutherland]

Maybe have a look at something like this. Haven't tried one but the reviews are quite favorable.
Good luck and keep us posted as to what you come up with!

Ken


https://www.duckworksbbs.com/product-p/dw-sc.htm

[Daiku]

The Japanese military is using the yuloh.

'Tsunami tuchman boat rescues cnn 2011' has some really good shots of this yuloh in action:

https://www.youtube.com/watch?v=DIPP9B1fnes

[Snowpetrel]

Originally Posted by Daiku

The Japanese military is using the yuloh.

'Tsunami tuchman boat rescues cnn 2011' has some really good shots of this yuloh in action:

Thanks, Good footage at 4:57 and 5:42. Seems like the light flat bottom boats aren't perfect as they get a fair bit of tailwag happening, but it shows the potential.

I used an old lifeboat sweep for years on my 26 footer. Mostly it was used as a stern thruster for manoeuvring under sail, but I could also scull her at about 1.5-2 knots for short bursts. For longer runs it was more efficient for me to set it up as an oar on one side of the boat.

I made it into a crude Yuloh a few times by rigging a lanyard to take the thrust. This made for a huge improvement in thrust to effort over sculling without the lanyard, but by that stage I had a small outboard so I didn't refine it any further, but the few times I used it this way convinced me that it's a good concept.

I like some of the work Sven Yrvind has done on his modern versions.

http://www.yrvind.com/yrvinds-yuloh/

And this looks like a pretty heavy boat being moved around via yuloh.
https://youtu.be/dceYiJDQoNo