tag:blogger.com,1999:blog-3580987459140037495.post7760449823541972197..comments2024-03-18T10:29:20.125-08:00Comments on TriloBoat Talk: A First Look at Vertical Sculling OarsDave Zhttp://www.blogger.com/profile/13241033623115158564noreply@blogger.comBlogger25125tag:blogger.com,1999:blog-3580987459140037495.post-88001736004608360252024-02-17T18:50:20.476-09:002024-02-17T18:50:20.476-09:00How much of the overall length of your sculling oa...How much of the overall length of your sculling oar is blade? Is it the same proportion as the Mockingull diagram, above?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-9938387379549768822023-11-12T15:59:40.793-09:002023-11-12T15:59:40.793-09:00I await with hot interest a lot more about the con...I await with hot interest a lot more about the construction, dimensions and implementation of your big boat sculling oar.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-68951409001691616632023-08-27T05:30:28.676-08:002023-08-27T05:30:28.676-08:00Hi,
I don't at the moment... once I'm bac...Hi,<br /><br />I don't at the moment... once I'm back in the USA I intend to update this post as we now have a lot of experience with the Martin oar.<br /><br />The blade we're using is 5ft long by about 10in deep in the belly. The total length with loom is (I think) 16ft. We set it up like a yuloh (deck lanyard and and a lanyard to position it outboard).<br /><br />More to come!<br /><br />Dave ZDave Zhttps://www.blogger.com/profile/13241033623115158564noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-74461199027066748152023-08-25T19:29:53.264-08:002023-08-25T19:29:53.264-08:00Do you have some dimensions, photos or design sket...Do you have some dimensions, photos or design sketches of your particular sculling oar?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-59303666234284502092020-03-06T13:35:39.866-09:002020-03-06T13:35:39.866-09:00Hi Peter,
We used a straight loom / no handle ver...Hi Peter,<br /><br />We used a straight loom / no handle version of the Martin MOCKINGJAY approach.<br /><br />It has been working very well... a significant improvement over our yuloh.<br /><br />Given our implementation (less blade area), we don't seem to reach quite the same top speed on a sprint(judging by wake). 16ft overall, it powers our T32x8 hull.<br /><br />But we maintain very nearly top speed with noticeably less effort. We can scull continuously for much longer periods without pause to rest. I think our overall (average) speed is higher.<br /><br />The hook definitely reduces the forearm effort for orienting the blade between strokes.<br /><br />More soon in a full post.<br /><br />Dave Z<br /><br />Dave Zhttps://www.blogger.com/profile/13241033623115158564noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-11952209285665229332020-03-05T19:39:43.495-09:002020-03-05T19:39:43.495-09:00How has yours been working with the Wayward?How has yours been working with the Wayward?Peterhttps://www.blogger.com/profile/09074125801234414010noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-67530733510160698252018-10-30T09:38:37.306-08:002018-10-30T09:38:37.306-08:00Hi Charlie,
Yes, it's important for the hook ...Hi Charlie,<br /><br />Yes, it's important for the hook to be on the upper edge. <br /><br />It's function is to twist the blade as you stroke side to side by dragging that upper edge behind the leading edge this orients the leading edge downward. <br /><br />Oriented thus, the whole blade wants to dive and thrust is forward. This tensions and is prevented by the lanyard at the forward end. As long as the operator doesn't fight the effect, things stay taut and efficient. <br /><br />If the hook were on the downside edge, the leading edge would twist UPward and thrust is backward, and the whole blade would want to skip to the surface. You'd need a strut (rather than a rope lanyard) to resist. <br /><br />It may help to picture the blade as one of a variable pitch propeller... It functions like a screw, screwing its way through the water. <br /><br />In theory, you could overpower the geometries of the oar (or yuloh) and scull backwards. I've tried it but without mastery. It's awkward and strenuous, but possible. Might even be worth practicing, <br /><br />Have fun!<br /><br />Dave ZDave Zhttps://www.blogger.com/profile/13241033623115158564noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-16935506864398730932018-10-29T19:21:27.698-08:002018-10-29T19:21:27.698-08:00Hi. I'm just beginning to research yulohs/scul...Hi. I'm just beginning to research yulohs/sculling oars as a means of propulsion. Is there a reason the vertical oars pictured here kick up at the inboard end, as opposed to down? In both cases, the intent of the kick (as I understand it) is to set the angle of the blade through the water, and either set up will do that, but an upwards kick means either a much longer oar is needed, or that the oar by necessity will sit much more shallow in the water. No doubt Mr Atsushi has done his homework and come up with the most effective design, but I struggle to understand the mechanics behind it.Charliehttps://www.blogger.com/profile/04300302571612280107noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-60822047488983668262017-03-14T22:06:22.960-08:002017-03-14T22:06:22.960-08:00Hi Tim,
He sure has an OPUS! So many good ideas, ...Hi Tim,<br /><br />He sure has an OPUS! So many good ideas, so little time.<br /><br />Those fish tail oars look very good to me, too. Once we're sailing again, I'd love to play with them.<br /><br />Dave ZDave Zhttps://www.blogger.com/profile/13241033623115158564noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-75266949395365935862017-03-14T14:47:07.983-08:002017-03-14T14:47:07.983-08:00l always liked the many contributions Atsashi Doi ...l always liked the many contributions Atsashi Doi has contributed to alternative boat design and simple drive units..<br />Here is another concept l find admirable, simple and portable..<br />https://www.youtube.com/watch?v=uW8MWFvT-EgAnonymoushttps://www.blogger.com/profile/17595981220646062661noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-33929157151141292982017-03-10T18:03:37.460-09:002017-03-10T18:03:37.460-09:00Hi MD,
From what I can tell, the downward vector ...Hi MD,<br /><br />From what I can tell, the downward vector may not be as different between the two as might be imagined. <br /><br />In many cases, the loom/blade for the AD oar and yulohs are at the same profile angles... once settled into the cross sweep, the transverse angle for both is about 45deg.<br /><br />However, my guess is that the AD will 'stand up' toward vertical easier than a yuloh... about the same as a ryo.<br /><br />Dave ZDave Zhttps://www.blogger.com/profile/13241033623115158564noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-38514200911044398832017-03-10T17:57:21.610-09:002017-03-10T17:57:21.610-09:00Hi Hans,
Big muscle groups are great to bring onl...Hi Hans,<br /><br />Big muscle groups are great to bring online! Especially if oaring over the long haul. 8\<br /><br />Dave ZDave Zhttps://www.blogger.com/profile/13241033623115158564noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-68220639805454096382017-03-09T16:21:54.129-09:002017-03-09T16:21:54.129-09:00I can't help thinking this would require less ...I can't help thinking this would require less exertion than an ordinary yuloh since most it would go to push. Alternately with a yuloh, push is a vector drive since a portion of the sculler's exertion goes to compelling the stern down on each scope. That would be squandered vitality I would think.Thanks for sharing this nice info expect some more in near future. educeviri of very nice information.<br /><a href="http://tjlug.org/" rel="nofollow">sailing cruises in san blas islands</a>md ashraful alamhttps://www.blogger.com/profile/16092135132596005782noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-62961647924970978192017-03-07T23:50:09.217-09:002017-03-07T23:50:09.217-09:00Hello Dave,
I use my oar on a small multihull, so...Hello Dave,<br /><br />I use my oar on a small multihull, so unfortunately I have no experience of a setup on a big boat. I wrote an article with some drawings of my setup. You can find it here : http://smalltrimarans.com/blog/how-to-scull-a-multihull/<br /><br />In my setup, the oarlock halfway the CE of the blade and the spot where you grab the oar sounds about right. <br />But you could experiment with "gearing" - change length of levers / area of the blade / frequency of the stroke.<br /><br />For bigger boats I would think it is important to be able to use more muscles than only you arm i.e. legs/upper body. The human power available is not very big so you might need all the muscles that can help to move a heavy boat.<br /><br />Good Luck, greetings from Amsterdam, HansHanshttps://www.blogger.com/profile/03880608136992580120noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-13921977980249409312017-03-07T21:28:17.276-09:002017-03-07T21:28:17.276-09:00Hi Hans,
You could be right that more force can b...Hi Hans,<br /><br />You could be right that more force can be applied to a shallow angled oar, and that would reduce any advantage. Atsushi Doi's Power Fin achieves a fully vertical blade with a horizontal loom, but at the cost of a much less stowable setup.<br /><br />Yulohs that angle high are worked primarily via the lanyard... did you try that?<br /><br />I'm thinking that the oarlock should be halfway between the point of lanyard attachment and the center of lateral resistance of the blade... does that seem about right?<br /><br />What size boat are using the oar on?<br /><br />Great to have some actual experience weighing in... thanks for writing!<br /><br />Dave Z Dave Zhttps://www.blogger.com/profile/13241033623115158564noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-69860735118764011152017-03-07T09:59:22.801-09:002017-03-07T09:59:22.801-09:00Hello Alan and Dave,
I use an AD sculling oar, an...Hello Alan and Dave,<br /><br />I use an AD sculling oar, and have had the same thought about the direction of the force. Therefor I use the oar with a lot steeper angle in the water than most of the other users I can find on the net (judging from videos/pictures). The difference in speed seems to be less then I expected though. It could be that easier handling of a shallower angled oar makes up for the loss in efficiency ?<br /><br />BTW the end of the stick from which the lanyard comes should be at the rotational axys of the oar/oarlock. (difficult to explain in English - hope it's clear).<br />Greetings, Hans Hanshttps://www.blogger.com/profile/03880608136992580120noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-80805727063963007992017-03-07T09:58:47.008-09:002017-03-07T09:58:47.008-09:00This comment has been removed by the author.Hanshttps://www.blogger.com/profile/03880608136992580120noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-88903607776024879282017-03-07T09:56:29.407-09:002017-03-07T09:56:29.407-09:00This comment has been removed by the author.Hanshttps://www.blogger.com/profile/03880608136992580120noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-38473462194327453892017-03-01T16:48:19.778-09:002017-03-01T16:48:19.778-09:00Yeah, huge like long. I dont remember now, but it ...Yeah, huge like long. I dont remember now, but it would have had to break down in at least two if not three bits. Davidhttps://www.blogger.com/profile/15888319075167956385noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-52072659184528181182017-02-27T17:15:50.897-09:002017-02-27T17:15:50.897-09:00Hi David,
Huge in what ways? E.g., length of oar,...Hi David,<br /><br />Huge in what ways? E.g., length of oar, length and/or depth of blade?<br /><br />Definitely may be the fatal flaw for larger boats. Some of that may be fudgeable, but we'll see!<br /><br />Dave ZDave Zhttps://www.blogger.com/profile/13241033623115158564noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-16405086726410468342017-02-27T10:23:51.255-09:002017-02-27T10:23:51.255-09:00I was looking into making an I-scull for my old bo...I was looking into making an I-scull for my old boat last year. I never did it, but I did get into contact with Mr. Atsushi for some advice and I found him very helpful and just a fine man all around. One thing he stressed to me was that while the basic shape is expressed in the patent drawings, the proportions must be adjusted to transom height and that of the oarsman. What I needed for a 22 foot sailboat was huge!Davidhttps://www.blogger.com/profile/15888319075167956385noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-81005746402686168162017-02-23T18:54:14.615-09:002017-02-23T18:54:14.615-09:00Yes, but did you ask in Japanese? -- DZ
Yes, but did you ask in Japanese? -- DZ<br /><br />Dave Zhttps://www.blogger.com/profile/13241033623115158564noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-51616361402095211022017-02-23T18:51:50.719-09:002017-02-23T18:51:50.719-09:00Hi Alan,
It may be similar... both make most of t...Hi Alan,<br /><br />It may be similar... both make most of their lateral pass at about the same angle, as far as I can tell, so both will tend to depress the stern (inboard lanyard counters the dive, so we don't have to).<br /><br />Hope to try one out, soon!<br /><br />WAYWARD's poking along. We've nearly finished the OCBs (almost a leeboard), and are picking away at the electrical system. Should go faster now that some cramped mountings are in place.<br /><br />Emptor Lux!<br /><br />Dave ZDave Zhttps://www.blogger.com/profile/13241033623115158564noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-13136206309859033022017-02-23T16:39:49.439-09:002017-02-23T16:39:49.439-09:00I distinctly asked that my sculling efforts on tha...I distinctly asked that my sculling efforts on that video not be published!!!Robertohttps://www.blogger.com/profile/18320063715736110902noreply@blogger.comtag:blogger.com,1999:blog-3580987459140037495.post-66588960871120712042017-02-23T06:07:12.073-09:002017-02-23T06:07:12.073-09:00It seems to me that this would require less effort...It seems to me that this would require less effort than a conventional yuloh since most it would go to thrust. Conversely with a yuloh, thrust is a vector force since some of the sculler's effort goes to forcing the stern down on each sweep. That would be wasted energy I would think. However, I don't KNOW. Your thoughts on that Dave? How's Wayward?Alan Joneshttps://www.blogger.com/profile/17633386901505182550noreply@blogger.com