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Thread: Birdwing mast design to benefit from new sail track composite material

  1. #106
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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by kenjamin View Post
    Daniel,

    Thanks for your interest in my birdwing bicycle. It is very much a design in progress. I built a bowsprit for it but managed to break the bottle cage hardware that I was depending on to secure the bowsprit. The laminated mahogany and spruce "cube" worked well at stepping the mast and not inhibiting the free rotation of the mast. In truth, I have only tried the design once and was scared to death during the first initial flights but soon became comfortable with the somewhat abrupt gybes. At that time the conditions were not very favorable for testing. It was a strong north wind, but the sand was too wet and soft, and I was missing the power of the headsail. I've managed to fix the bottle cage hardware and only need to hem the edges of the headsail to go at the testing again. Ideally, in my area, a good stiff east wind or west wind and a low tide would allow me to broad reach all the way from St. Augustine to Daytona beach and back. I definitely am not finished exploring the birdwing bike design but it seems like I spend too much time blabbing about birdwing mast design to actually get anything done on it. In the meantime, here's a picture of what it should look like when it's finished.



    I can only guess where the bird wing and your imagination might go with this beauty! maybe camp/beach cruising!


  2. #107
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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by kenjamin View Post
    Daniel,

    Thanks for your interest in my birdwing bicycle. It is very much a design in progress. I built a bowsprit for it but managed to break the bottle cage hardware that I was depending on to secure the bowsprit. The laminated mahogany and spruce "cube" worked well at stepping the mast and not inhibiting the free rotation of the mast. In truth, I have only tried the design once and was scared to death during the first initial flights but soon became comfortable with the somewhat abrupt gybes. Wind gusts were not a problem but some of the gybes put new hair on my chest! At that time the conditions were not very favorable for testing. It was a strong north wind, but the sand was too wet and soft, and I was missing the power of the headsail. I've managed to fix the bottle cage hardware and only need to hem the edges of the headsail to go at the testing again. Ideally, in my area, a good stiff east wind or west wind and a low tide would allow me to broad reach all the way from St. Augustine to Daytona Beach and back. I definitely am not finished exploring the birdwing bike design but it seems like I spend too much time blabbing about birdwing mast design to actually get anything done on it. In the meantime, here's a picture of what it should look like when it's finished.





    Inspiration for the birdwing bicycle:


    You may enjoy this then:


  3. #108
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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by Clarkey View Post
    You may enjoy this then:

    Thanks Clarkey, that's awesome! I really liked the simplicity of Patterson's invention. I found more information about it here that you might want to check out:
    http://www.oldbike.eu/museum/1940s/1...cle-sail-bike/

  4. #109
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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by kenjamin View Post
    Thanks Clarkey, that's awesome! I really liked the simplicity of Patterson's invention. I found more information about it here that you might want to check out:
    http://www.oldbike.eu/museum/1940s/1...cle-sail-bike/
    I'm not sure about the sheeting method, I think your arm would get tired/ drain of blood held over your head on a multi mile reach...I like yor lines Ken, provided you can keep them out of the wheels and brakes. I wonder why the video never showed the clarkey bike sailing for a long distance straight line or on a speed run?

    looks very similar to the hotel ormond bike... looks like fun, I'll have to keep an eye out for big wheel bikes on "sail"

  5. #110
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    Default Re: Birdwing mast design to benefit from new sail track composite material

    a quick review of C list shows several "Fat Bikes" with the +++ size tires, disc brakes for 100-150$...

    I may have my first K.J. "Bird Bike" in my future. what's not to love with the colapsable rig you can ride the length of a beach, 2-8 miles locally then fold the rig, ride over a bridge and back on the beach, Cape Anne- York Maine is about 40 miles of beach... never mind the Cape!

  6. #111
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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Daniel, I certainly do not mind if you want to build a birdwing mast and put it on your bicycle as long as you do not bust your buttocks and blame me. The cube that I built is good for stepping the mast as well as storing it on the bike because of its open architecture. As for the lines, I'm glad you mentioned that. Maybe it would be a good idea to house all the lines with polyethylene PEX pipe to keep the lines out of the spokes because that could be some real trouble if you know what I mean. I would recommend using aircraft quality spruce scraps from Aircraft Spruce at $38 per bundle. Just don't start a business selling birdwing masts here in the good old USA or there might be a feeding frenzy of blood hungry shark lawyers and nobody wants that (except the lawyers). PM me if you want to pick my brain some more on birdwing mast construction.
    Last edited by kenjamin; 08-09-2017 at 08:19 AM.

  7. #112
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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Here's another vote for a continuously curving sail-setting spar from mother nature:







    Looks a lot like a birdwing mast to me!

  8. #113
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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by kenjamin View Post
    Daniel, I certainly do not mind if you want to build a birdwing mast and put it on your bicycle as long as you do not bust your buttocks and blame me. The cube that I built is good for stepping the mast as well as storing it on the bike because of its open architecture. As for the lines, I'm glad you mentioned that. Maybe it would be a good idea to house all the lines with polyethylene PEX pipe to keep the lines out of the spokes because that could be some real trouble if you know what I mean. I would recommend using aircraft quality spruce scraps from Aircraft Spruce at $38 per bundle. Just don't start a business selling birdwing masts here in the good old USA or there might be a feeding frenzy of blood hungry shark lawyers and nobody wants that (except the lawyers). PM me if you want to pick my brain some more on birdwing mast construction.
    Actually I believe Daniel can start selling them commercially tomorrow without any worries about either lawyers or sharks (just be careful riding on bridges with low railings). Your patent specifically covers sailboats and I quote from your patent.

    1.A sail supporting assembly for a sailing vessel having ahull with a keel and gunwales, comprising:

    It doesn't cover any other use of the birdwing mast. Not on a bicycle or a iceboat or a skateboard. And even on a sailboat, none of the examples you have built meet the requirements of the patent, so none of them or copies are protected by your patent and likely can be freely copied by anyone. This was outlined in my previous post, #69

    I looked at your patent and am a bit perplexed. You have a total of one claim:

    1. A sail supporting assembly for a sailing vessel having a
    hull with a keel and gunwales, comprising 14 elements a. through n. They are in the form of a list a and b and c......and n.


    If I understand patent claim construction correctly, the only invention covered must contain all of those 14 elements. So if I build one and it doesn't have a curved sliding mast extender as described in m. and n. there would be no infringement according to law. Or as b. states the rotating mast must be perpendicular to the keel, one could have the mast at a 2° angle to the keel.


    Here is a link to the patent https://patentimages.storage.googlea.../US8739720.pdf

    And in response to your previous post. FSU has nothing to do with this patent any longer, you own it and no, I don't really plan on suing you as that would be a colossal waste of my time as well as there is no basis for a lawsuit unless the Dutch boat designer wants to get involved and even then it is too late as he has shown his invention in public for way too long to warrant any patent protection.

    It is clear that you thought up the birdwing mast, but as the letter/picture from Iain Oughtred clearly shows, you were not the first to invent it (back then it was first to invent, not first to file) so likely your patent isn't valid based on that letter/picture (which you yourself posted). In either case you didn't disclose all known prior art to the patent office as required and that is grounds for revocation of the patent in itself.

    Perhaps you should submit the letter and picture to the USPTO and get their opinion. It would be interesting to see what response you get.

    This is the last time I will post on this thread as I it looks to me more and more like an exercise in self-promotion. You are looking for someone to fund the research you should have done years ago, but didn't. You are hoping for someone to infringe your patent and then find free legal help to sue them in order to get free publicity. And you are praying to find someone to manufacture/sell your 'invention' without putting up and risking any your own money. Good luck with all that.

    Alan
    https://sites.google.com/site/helium12sofsailboat/

  9. #114
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    Default Re: Birdwing mast design to benefit from new sail track composite material

    I stand guilty of being poor enough to know that, at the time, I did not have the four thousand dollars that Florida State University wanted to charge me for aerodynamic studies of the design for which they were granted a patent. I did not understand why the research institution known as FSU would not do the very basic simple aerodynamic research necessary to greatly increase the value of their patent, especially considering their great available resources of facilities and well-trained engineers. FSU made it very easy for a staff member to come forward with an idea that was worthy of a patent but they had very little mechanism in place to capitalize on a staff originated idea once its patent had been granted.

    As much more of an artist type than a businessman or lawyer, there is no doubt that I made mistakes in my exploration of the curved mast design that my long-time fishing buddy forced me to create. I’ve always thought that the catalyst for an invention should get more credit and financial reward for the part they may have played in the creation of a design but that is not the law or at least my understanding of the law. I never thought that another design which needed “expensive hardware” to work properly and displayed no “sickle shape” whatsoever (in the artwork to which I became aware) ever had any “basis” for consideration. In my mind, it was the sickle shape, the key element in my design, which cleanly separated the Dutch boat’s design from mine. But as I stated, I’m not a lawyer so I mostly relied on FSU’s patent lawyer for expertise. Even though I am not a lawyer, I am a human being and still allowed to have an opinion. It was my opinion that the Dutch boat’s masts had no sickle-shape to them at all and as Iain Oughtred stated they needed expensive hardware to work properly so my opinion was grounded in fact, not as it has been implied, a purposeful oversight.

    As for the charge of self-promotion, as an inventor, especially one without a lot of money with which to work, it is hard to separate one’s self from one’s invention. I doubt that Wilbur Wright worried about self-promotion when he made his now famous flight 20 miles up and down the Hudson River in 1909. According to Russell Freedman’s book, “THE WRIGHT BROTHERS How They Invented the Airplane,” the flight “was watched by an estimated one million New Yorkers, almost none of whom had ever seen an airplane in the air before.” Wilbur carried a red canoe on the undercarriage of the airplane in case of a landing in the river. Surely if he had been worried about self-promotion he would have painted it gray or blue or green – almost any color other than red! I rest my case.

    For the purpose of discussion, let’s just assume the patent is worthless so we can discuss the merits of the design itself rather than getting bogged down with details of law and the power or value of the associated patent. Also, for the record, I’ve never prayed about finding a manufacturer or seller for the birdwing mast invention but maybe I should start. Nothing else has worked.

    As an artist type, it’s not a lot of fun for me to have to put on my lawyer cap and defend myself on an international forum, but I do thank you, Alan, for wishing me luck in my endeavors with my invention. So far I’ve been pretty lucky, I haven’t killed myself or anyone else with it and for that I am grateful. Also it’s not everyday one gets the opportunity to buy a U.S. patent for one U.S. dollar. Yes, I’ve been lucky but that’s not a crime either – at least as far as I know.

  10. #115
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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by kenjamin View Post
    Here's another vote for a continuously curving sail-setting spar from mother nature:







    Looks a lot like a birdwing mast to me!
    But where's the slightest evidence that the forces and flow over a butterfly wing are similar to that affecting a boat rig? To what extent does the butterfly wing compromise aerodynamic efficiency because of other constraints, such as limits of root bending moment? Why use a butterfly's leading edge as a model instead of an albatross' straighter wing?

    Why assume that "natures shapes" are better for manmade uses? Cars don't have legs; airplanes don't flap their wings. There's nothing in nature that has a centreboard and a sail and can go upwind. Nature isn't always superior for the things man does.

    If the curved leading edge is superior in boat rigs why have they been tried so often and abandoned so often?

    Wilbur Wright started off by reading everything the experts had written before him. Surely if someone does come along with an interest in financially supporting the birdwing mast, there will be questions about the theory behind it. Why not read Tom Speer, Frank Bethwaite and the Smith lecture just so you can discuss the aerodynamics involved?
    Last edited by Chris249; 08-10-2017 at 07:11 PM.

  11. #116
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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Chris, inventors look to nature for answers because sometimes they find answers there. It is a proven formula for success in the world of invention. Even if you do not find an answer, you may find an insight. When I found a dead butterfly on the sidewalk the other day, I was struck by how similar the butterfly's continuously curving sail-setting spar was so similar to my birdwing mast. I wondered why that would be. Please understand that the following is only the opinion of an old retired graphics guy, not a claim of some kind by an inventor. I believe aerodynamics are involved because butterflies are creatures of flight. I have no idea how well they can get to windward but I strongly suspect they can. The other design element of their wing design is the strength of the leading edge (the spar) that supports their wing sail area. Even though I ended up getting an art degree at FSU, at Saint Johns River Junior College, I did fairly well in advanced physics with calculus. My opinion is that the design of the curvature of a butterfly's spar also has something to do with strength as well. Along a curved path there is greater length for sail supporting structure per unit of length as compared to a straight spar. The curvature also better supports balanced sail area in my opinion. I have no idea why that is important to a butterfly, but there it is. Look at it. However, I can clearly show why that is an advantage for a birdwing mast.

    In the bottom photo of the butterfly, the wings are folded up to a position of minimum drag for a butterfly (just my opinion). In the last couple of days, I received the latest 3D rendering from Bedard Yacht Design of Muri-Maru, my next boat build. I had requested the view of Muri-Maru as she would look motoring (or rowing) directly into a head wind. The masts would have self-rotated to a position of lowest aerodynamic drag and the front view would look like this.



    Most people do not realize that birdwing masts can present such a narrow straight line to the wind. (more opinion) But now witness what a birdwing rig can present to the airflow when being driven downwind by a tail wind.



    Quite a bit of difference, right? To me one of the beautiful aspects of my design is how the two masts actually overlap for downwind work (not opinion – fact!). That overlap certainly better stops the flow of air and provides added thrust for downwind runs and keep in mind that Muri-Maru is being built especially for the Texas 200 where a following wind is often the case. In my opinion, it is only very recently that it is possible to execute the correct taper for such masts as mine when rendered in carbon fiber. Without 3D computer printing, how in the world could you ever get the taper correct along the curved sweep of the birdwing mast in carbon fiber? In spruce, you can machine in the taper by making the side profile much thicker at the bottom of the mast while the thickness of the side profile can be much thinner at the top. With my set up in my backyard, I can precisely control the taper of my masts so that, at least in theory, I can design my curved mast to be exactly as strong and as thick as it needs to be at the bottom and also as thin and as light as it can be at the top. It is the taper that is so impossible for me to attain in carbon fiber. There is no argument from me about carbon fiber masts having better performance potential than laminated spruce. But a poor old retired illustrator for the State of Florida does not have the money to hire all the expertise that it would take to design and build the perfect carbon fiber birdwing mast. And worst, I simply do not have the time or the ability to learn all that expertise myself and even if I did, I still wouldn't have the money to computer optimize the design aerodynamically or to come up with the proper tooling to execute the optimum design of a carbon fiber birdwing mast. Where does that leave me? It leaves me blabbing about the design on a boat forum and paying for renderings that help people look beyond my crude laminated spruce prototypes and begin to see birdwing masts as state-of-the-art carbon fiber creations that definitely have some interesting design characteristics including the ability to set balanced sail are with a single spar, ability to self-rotate to take best advantage of wind direction when working to windward and the mentioned overlap of sail area working downwind.

    The other thing I think you are missing is that birdwing masts in carbon fiber do not have to be low aspect ratio rigs. In my opinion, they could have a similar profile of almost any outstretched bird wing on the planet including the albatross. To me, this means a very large range of birdwing mast designs to meet the required performance standards of any particular application. It's called versatility of design. In my view, there can be a birdwing mast for bicycles as well as one for sail-assisted container shipping. It's not what birdwing masts are today, it's what they can become in the future.
    Last edited by kenjamin; 08-11-2017 at 09:42 AM.

  12. #117
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    Default Re: Birdwing mast design to benefit from new sail track composite material

    That overlap certainly better stops the flow of air and provides added thrust for downwind runs...
    Ha ha ha! You still haven't looked up how lift works?! Or how fast sailboats can sail downwind faster than mere wind speed by using apparent wind to generate lift above and beyond mere drag?

    Good grief, Kenjamin! This isn't top-secret material or anything like that. They figured this stuff out way back in the 20th century. You could bother to do the tiniest possible amount of actual research into how sails and boats actually work, you know.

    I am going out dinghy sailing out of Changi Sailing Club with some friends tomorrow. I will be delighted if any of our competitors have as poor a grasp of basic sailing dynamics as you as to try to "stop the flow of air" on any point of sail. Crikey!


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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by kenjamin View Post
    I stand guilty of being poor enough to know that, at the time, I did not have the four thousand dollars that Florida State University wanted to charge me for aerodynamic studies of the design for which they were granted a patent. I did not understand why the research institution known as FSU would not do the very basic simple aerodynamic research necessary to greatly increase the value of their patent, especially considering their great available resources of facilities and well-trained engineers. FSU made it very easy for a staff member to come forward with an idea that was worthy of a patent but they had very little mechanism in place to capitalize on a staff originated idea once its patent had been granted.

    As much more of an artist type than a businessman or lawyer, there is no doubt that I made mistakes in my exploration of the curved mast design that my long-time fishing buddy forced me to create. I’ve always thought that the catalyst for an invention should get more credit and financial reward for the part they may have played in the creation of a design but that is not the law or at least my understanding of the law. I never thought that another design which needed “expensive hardware” to work properly and displayed no “sickle shape” whatsoever (in the artwork to which I became aware) ever had any “basis” for consideration. In my mind, it was the sickle shape, the key element in my design, which cleanly separated the Dutch boat’s design from mine. But as I stated, I’m not a lawyer so I mostly relied on FSU’s patent lawyer for expertise. Even though I am not a lawyer, I am a human being and still allowed to have an opinion. It was my opinion that the Dutch boat’s masts had no sickle-shape to them at all and as Iain Oughtred stated they needed expensive hardware to work properly so my opinion was grounded in fact, not as it has been implied, a purposeful oversight.

    As for the charge of self-promotion, as an inventor, especially one without a lot of money with which to work, it is hard to separate one’s self from one’s invention. I doubt that Wilbur Wright worried about self-promotion when he made his now famous flight 20 miles up and down the Hudson River in 1909. According to Russell Freedman’s book, “THE WRIGHT BROTHERS How They Invented the Airplane,” the flight “was watched by an estimated one million New Yorkers, almost none of whom had ever seen an airplane in the air before.” Wilbur carried a red canoe on the undercarriage of the airplane in case of a landing in the river. Surely if he had been worried about self-promotion he would have painted it gray or blue or green – almost any color other than red! I rest my case.

    For the purpose of discussion, let’s just assume the patent is worthless so we can discuss the merits of the design itself rather than getting bogged down with details of law and the power or value of the associated patent. Also, for the record, I’ve never prayed about finding a manufacturer or seller for the birdwing mast invention but maybe I should start. Nothing else has worked.

    As an artist type, it’s not a lot of fun for me to have to put on my lawyer cap and defend myself on an international forum, but I do thank you, Alan, for wishing me luck in my endeavors with my invention. So far I’ve been pretty lucky, I haven’t killed myself or anyone else with it and for that I am grateful. Also it’s not everyday one gets the opportunity to buy a U.S. patent for one U.S. dollar. Yes, I’ve been lucky but that’s not a crime either – at least as far as I know.
    I am fairly new and inexperienced with the forum, but I've been following along. It has been a very interesting discussion and I've learned a lot, but it does seem to be a bit of self promotion here, which isn't really bad, except the rules prohibit it, right?

    I am careful not to post or present my own work on this board in any way that could be framed as an advertisement or promotion.

    Perhaps that was where the self promotion comment came from? Not that self promotion is bad, per se, but isn't suppodsed to happen here, eh?

    I wish you luck, too. I'm not feeling it, but I can plainly see you are, and I hope you finally get to actualize the mast and rig you want some day.

    Peace,
    Robert

  14. #119
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    Default Re: Birdwing mast design to benefit from new sail track composite material

    So when John Welsford or Richard Woods start a thread on one of their designs, that is somehow not self-promotion? I think like those designers, WoodenBoat forum has granted me a little leeway in that area because I bring to the table an interesting design that I have been writing about on this forum for ten years now and at present there is much more money coming out of my pocket in regards to the design and no money coming in. There are no retail sales of my birdwing design at present.

    I also bring to the discussion table the inventor's perspective which many find interesting and like to talk about.

    When I discussed this with Scott, the forum referee, he said that I could talk about the patent when people asked about it. I waited eight months before someone asked the patent and let the cat out of the bag so I could talk about it.
    Last edited by kenjamin; 08-11-2017 at 09:36 AM.

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by kenjamin View Post
    So when John Welsford or Richard Woods start a thread on one of their designs, that is somehow not self-promotion? I think like those designers, WoodenBoat forum has granted me a little leeway in that area because I bring to the table an interesting design that I have been writing about on this forum for ten years now and at present there is much more money coming out of my pocket in regards to the design and no money coming in. There are no retail sales of my birdwing design at present.

    I also bring to the discussion table the inventor's perspective which many find interesting and like to talk about.

    When I discussed this with Scott, the forum referee, he said that I could talk about the patent when people asked about it. I waited eight months before someone asked the patent and let the cat out of the bag so I could talk about it.
    Sure.

    Do whatever.

    But, you seemed to get a little bent about a self promotion comment, and I simply offered a reason somebody may have mentioned it.

    You do whatever you want.

    Peace,
    Gone

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by amish rob View Post
    Sure.

    Do whatever.

    But, you seemed to get a little bent about a self promotion comment, and I simply offered a reason somebody may have mentioned it.

    You do whatever you want.

    Peace,
    Gone
    I'm not one to complain about self promotion, I've been on the forum for 10+- years and only gotten 1 job from it... which turned out to be a DUD... there are lots better places to go to "self promote"

    I'm very interested in what professionals have to say and don't want them to feel stifled about bring up and sharing their latest projects... as long as nothing is offered for sale... I'm very interested in whats for sail! asl long as its tasteful and it is not annoying, confined to primarily 1 thread or relevant posts in other threads I'm fine and would encourage talking about for profit projects.

    Kens well within those bounds as I see it.

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by Daniel Noyes View Post
    I'm not one to complain about self promotion, I've been on the forum for 10+- years and only gotten 1 job from it... which turned out to be a DUD... there are lots better places to go to "self promote"

    I'm very interested in what professionals have to say and don't want them to feel stifled about bring up and sharing their latest projects... as long as nothing is offered for sale... I'm very interested in whats for sail! asl long as its tasteful and it is not annoying, confined to primarily 1 thread or relevant posts in other threads I'm fine and would encourage talking about for profit projects.

    Kens well within those bounds as I see it.
    Yes. As is fairly typical here, I simply attempted to tie together logic from separate posts and explain stuff. People here seem to read past each other or skim posts quite often.

    Someone wrote about self promotion, so Ken defended the notion.

    I simply proposed one reason the notion of self promotion might have been raised.

    I have no dog in the fight.

    Peace,
    Robert

  18. #123
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    Default Re: Birdwing mast design to benefit from new sail track composite material

    How is 3D printing relevant for a carbon fiber mast?
    I believe a lot of moulds have been built even before CNC machines. A carbon mast in any form might get vacuum laminated over some machines foam or into 2 separate molds...
    Normally they get CNC wound.



    Manufacturing a mast like yours would be a nightmare.

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by amish rob View Post
    Sure.

    Do whatever.

    But, you seemed to get a little bent about a self promotion comment, and I simply offered a reason somebody may have mentioned it.

    You do whatever you want.

    Peace,
    Gone
    Blabbing about my birdwing mast design on this forum is my hobby. Sure I dream about getting money out of the patent someday and if you had a U.S. patent, you would too. But what I really enjoy is talking with other folks about the birdwing mast design and trying to learn what other peoples' take is on it. By labeling me as a self-promoter, you are threatening an enjoyable hobby of mine. Of course I'm going to be upset.

  20. #125
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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by Daniel Noyes View Post
    I'm not one to complain about self promotion, I've been on the forum for 10+- years and only gotten 1 job from it... which turned out to be a DUD... there are lots better places to go to "self promote"

    I'm very interested in what professionals have to say and don't want them to feel stifled about bring up and sharing their latest projects... as long as nothing is offered for sale... I'm very interested in whats for sail! asl long as its tasteful and it is not annoying, confined to primarily 1 thread or relevant posts in other threads I'm fine and would encourage talking about for profit projects.

    Kens well within those bounds as I see it.
    Here's that photo of the extra flotation Sea Pearl I've been meaning to send you. From one human being to another, thanks!


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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by James McMullen View Post


    Ha ha ha! You still haven't looked up how lift works?! Or how fast sailboats can sail downwind faster than mere wind speed by using apparent wind to generate lift above and beyond mere drag?

    Good grief, Kenjamin! This isn't top-secret material or anything like that. They figured this stuff out way back in the 20th century. You could bother to do the tiniest possible amount of actual research into how sails and boats actually work, you know.

    I am going out dinghy sailing out of Changi Sailing Club with some friends tomorrow. I will be delighted if any of our competitors have as poor a grasp of basic sailing dynamics as you as to try to "stop the flow of air" on any point of sail. Crikey!

    Thanks for the downwind sailing tip. However sometimes the seaway is too narrow and commercial barge or freighter traffic is too heavy. In the Texas Intercoastal Waterway people who tack back and forth in front of the commercial traffic run the risk of being run over by a 300' barge being pushed by a tugboat. If the tugboat captain happens to notice he ran over someone, they might be able to retrieve your body. If not, a guy could also get chopped up by the tug's propellors into bite-sized chunks for the bull sharks. Whatever is left over after the sharks will surely be eaten by the crabs, stingrays and catfish. So tacking downwind is not always a good idea. Plus, in Texas in the middle of summer any body motion sailing just means you are going to burn more calories and get even hotter. The Texas 200 is much less about speed and much more about survival.
    Last edited by kenjamin; 08-12-2017 at 08:21 AM.

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by heavyweather View Post
    ...
    Manufacturing a mast like yours would be a nightmare.
    My hope is that what some people might see as a nightmare, others could see as challenging once-in-a-lifetime opportunity.

    3D carbon fiber printing means that any shape defined by a computer is possible to be printed out. My mast design has already been defined by Bedard Yacht Design.
    Last edited by kenjamin; 08-12-2017 at 08:27 AM.

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by kenjamin View Post
    Blabbing about my birdwing mast design on this forum is my hobby. Sure I dream about getting money out of the patent someday and if you had a U.S. patent, you would too. But what I really enjoy is talking with other folks about the birdwing mast design and trying to learn what other peoples' take is on it. By labeling me as a self-promoter, you are threatening an enjoyable hobby of mine. Of course I'm going to be upset.
    Perhaps reading posts carefully should become part of your hobby...

    I simply attempted to create a logical bridge. Remember, you were wringing your hands about Wilbur Wright before I, stupidly, I admit, tried to intervene and provide some logic to the self promotion discussion.

    I already said you should do what you want. My entire reasoning was to help you maybe be able to keep this going here, because, as I clearly explained, I am fairly new to the forum and how it works. I didn't want the thread to go away because it tread on some toes.

    You have to just go into defensive attack mode, I guess? I don't know.

    But, keep jabbing at me. Let me know more how I ruined your day and attacked your whole world by expressing my opinion. Sheesh.

    Peace,
    Robert

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by kenjamin View Post
    Thanks for the downwind sailing tip. However sometimes the seaway is too narrow and commercial barge or freighter traffic is too heavy. In the Texas Intercoastal Waterway people who tack back and forth in front of the commercial traffic run the risk of being run over by a 300' barge being pushed by a tugboat. If the tugboat captain happens to notice he ran over someone, they might be able to retrieve your body. If not, a guy could also get chopped up by the tug's propellors into bite-sized chunks for the bull sharks. Whatever is left over after the sharks will surely be eaten by the crabs, stingrays and catfish. So tacking downwind is not always a good idea. Plus, in Texas in the middle of summer any body motion sailing just means you are going to burn more calories and get even hotter. The Texas 200 is much less about speed and much more about survival.
    it's not about tacking downwind. As James said, even in a boat that runs square, you don't want to "stop the flow of air". That's why in Lasers, for example, you always try to trim the sail to have flow even when running square; it's why we run by the lee with leach-to-luff flow and then head up to get luff-to-leach flow, rather than going in a straight line with the flow of air stopped. It's why on a symmetrical spinnaker boat running square like a J/24, you ease the sheet until the luff starts folding - because that means the sail is eased as far as possible and the wind is flowing from the luff to the leach.

    This is sailing 101.

    In my town the average high temp in the hottest month is 81, compared to 90 at Magnolia Island when the Texas 200 is on. No one goes to survival mode when racing, even on days that are over the century. Most of the serious sailors still throw their boats through roll tacks, the windsurfers still pump flat out when racing, even when there's no wind to cool things down.
    Last edited by Chris249; 08-13-2017 at 05:52 AM.

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by kenjamin View Post
    Chris, inventors look to nature for answers because sometimes they find answers there. It is a proven formula for success in the world of invention. Even if you do not find an answer, you may find an insight. When I found a dead butterfly on the sidewalk the other day, I was struck by how similar the butterfly's continuously curving sail-setting spar was so similar to my birdwing mast. I wondered why that would be. Please understand that the following is only the opinion of an old retired graphics guy, not a claim of some kind by an inventor. I believe aerodynamics are involved because butterflies are creatures of flight. I have no idea how well they can get to windward but I strongly suspect they can.

    Yes, inventors find inspiration in nature. The point is that some of them do not apply to what humans do. Secondly, why refer only to some examples in nature rather than the examples that do not, such as straight-winged birds? It appears that you are highlighting examples that "support" your case and ignore the ones that don't. Why not look at both types and learn why they differ and how those principles apply to sailing rigs?

    The other design element of their wing design is the strength of the leading edge (the spar) that supports their wing sail area. Even though I ended up getting an art degree at FSU, at Saint Johns River Junior College, I did fairly well in advanced physics with calculus. My opinion is that the design of the curvature of a butterfly's spar also has something to do with strength as well. Along a curved path there is greater length for sail supporting structure per unit of length as compared to a straight spar. The curvature also better supports balanced sail area in my opinion. I have no idea why that is important to a butterfly, but there it is. Look at it. However, I can clearly show why that is an advantage for a birdwing mast.

    If getting want more sail for a certain luff length is important, why not choose the lighter, more gust efficient and structurally superior round mast and just add a couple of inches more on the boom or sail chord?

    In the bottom photo of the butterfly, the wings are folded up to a position of minimum drag for a butterfly (just my opinion). In the last couple of days, I received the latest 3D rendering from Bedard Yacht Design of Muri-Maru, my next boat build. I had requested the view of Muri-Maru as she would look motoring (or rowing) directly into a head wind. The masts would have self-rotated to a position of lowest aerodynamic drag and the front view would look like this.



    Most people do not realize that birdwing masts can present such a narrow straight line to the wind. (more opinion) But now witness what a birdwing rig can present to the airflow when being driven downwind by a tail wind.



    Quite a bit of difference, right? To me one of the beautiful aspects of my design is how the two masts actually overlap for downwind work (not opinion – fact!). That overlap certainly better stops the flow of air and provides added thrust for downwind runs and keep in mind that Muri-Maru is being built especially for the Texas 200 where a following wind is often the case. In my opinion, it is only very recently that it is possible to execute the correct taper for such masts as mine when rendered in carbon fiber. Without 3D computer printing, how in the world could you ever get the taper correct along the curved sweep of the birdwing mast in carbon fiber?

    People have been building carbon wing masts with curved edges for decades. It is a fact that you do not need 3d printing to do it. Even a "sacrificial" lighweight former with carbon laid on it will work well as a "low tech" method.

    In spruce, you can machine in the taper by making the side profile much thicker at the bottom of the mast while the thickness of the side profile can be much thinner at the top. With my set up in my backyard, I can precisely control the taper of my masts so that, at least in theory, I can design my curved mast to be exactly as strong and as thick as it needs to be at the bottom and also as thin and as light as it can be at the top. It is the taper that is so impossible for me to attain in carbon fiber. There is no argument from me about carbon fiber masts having better performance potential than laminated spruce. But a poor old retired illustrator for the State of Florida does not have the money to hire all the expertise that it would take to design and build the perfect carbon fiber birdwing mast. And worst, I simply do not have the time or the ability to learn all that expertise myself and even if I did, I still wouldn't have the money to computer optimize the design aerodynamically or to come up with the proper tooling to execute the optimum design of a carbon fiber birdwing mast. Where does that leave me? It leaves me blabbing about the design on a boat forum and paying for renderings that help people look beyond my crude laminated spruce prototypes and begin to see birdwing masts as state-of-the-art carbon fiber creations that definitely have some interesting design characteristics including the ability to set balanced sail are with a single spar, ability to self-rotate to take best advantage of wind direction when working to windward and the mentioned overlap of sail area working downwind.

    The other thing I think you are missing is that birdwing masts in carbon fiber do not have to be low aspect ratio rigs. In my opinion, they could have a similar profile of almost any outstretched bird wing on the planet including the albatross. To me, this means a very large range of birdwing mast designs to meet the required performance standards of any particular application. It's called versatility of design. In my view, there can be a birdwing mast for bicycles as well as one for sail-assisted container shipping. It's not what birdwing masts are today, it's what they can become in the future.
    Why you think the ability to self rotate when working to windward is a feature of birdwing masts? It's a feature of every wing mast and lots of other masts. The first boat I had as a kid had a self rotating mast. So does an Olympic Finn, designed in the 1940s and which used rig concepts that were even older. There are literally thousands of boats out there with self-rotating wingmasts.

    Out of interest, have you read Tom Speer's pieces on wingmast aerodynamics yet? He's a top man in the field and he can explain things to laypeople. Why not take the time to read his information?
    Last edited by Chris249; 08-13-2017 at 05:54 AM.

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    First of all, do not try to tell me about the conditions I faced in the first day of the 2016 Texas 200. I was there. You were not, right? I'm a Florida boy. I know what 90° F feels like. South Texas at Port Isabel was a whole new level of misery for me. The weather report said to expect 100° temperatures and 20 to 30 knot winds. It was like trying to survive in the nozzle of a hairdryer on high. I tried to do as the pros of the event do and cover up all body skin with loose lightweight breathable clothing but I got so hot I started getting heat stroke. When one is solo on his boat and getting dizzy, it is a survival situation.

    Secondly, when it comes to a carbon fiber, state-of-the-art, birdwing ketch rig, both you and I are arguing from a point of ignorance. Nobody knows how good it will work with its overlapping sails for downwind work. That's the whole point of the exercise! To explore a new design and see what it has to offer. It's called experimentation. If you want to be content with the status quo, that is your right but don't waste your time telling me what to do.

    Thirdly, the amount of time the average bird spends presenting a straight leading edge to the airflow is extremely small. Most birds do not even have that ability. If you were an old retired guy who rides his bicycle almost every day and studies birds, you would know that. Even the buzzards that daily climb the updraft from the hospital's parking lot (next to my house) DO NOT PRESENT a straight edge to the leading edge of their wings to the airflow! It is actually reverse curvature with the ends of their wings curved forward from the rest of the length of their wings. If you watched them climbing everyday, you would know that. Also if you think that albatrosses have straight wings, you sir, need a new straight edge!

    And lastly, what has been so impossibly difficult up to now is not the curvature of a carbon fiber, state-of-the-art birdwing mast – it's the perfect taper of a mast with extremely efficient airfoil cross sections set along a continuously curved path that is so darn difficult to achieve. It is my opinion (not a claim) that such a perfect taper for a birdwing mast with super efficient aerodynamic cross sections can best be described, defined, and designed using the latest most powerful software, top of the line computers and a knowledgable, well-trained human being that knows how to take best advantage of his facilities. That is what I would like to buy and try next. Why would I not want to take advantage of the latest technology to perfect a design for which I already have a patent?
    Last edited by kenjamin; 08-13-2017 at 07:42 AM.

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Since when was I telling you what to do? All I'm doing is asking questions and pointing out some facts, such as the basic one that you don't want to stop the flow of air over a rig.

    No one has to be ignorant about downwind aerodynamics, whether we're talking one mast or two or wing-style masts or conventional ones. There is an enormous amount of information about rig aerodynamics that is available. There is CFD work, and wind tunnel photographs and results, and basic aerodynamics theories that are explained by experts. There are speed record sailors who run wind tunnels, America's Cup winning sailmakers and sail trimmmers, and world champion sailmakers who you can talk to. None of this shows any reason why two small-chord masts will perform particularly well downwind.

    Thousands of people have many hundreds of hours experience with small-chord and other wing-type masts downwind. This is not an area of ignorance.

    I am a fairly old semi-retired guy. I do ride by bicycle most days. I do watch birds, and I've rescued seabirds on more than one occasion. The most recent was a shearwater we saved over Easter. Like many birds that fly vast distances it does not have a swept, highly curved and low-aspect wing; the shearwater, gannet,albatross etc have high aspect wings with very little sweep. So the question - and sentences that end with a "?" are questions - is why concentrate on butterflies and not soaring birds?

    The query about why we allegedly need 3D printing to "get the taper correct along the curved sweep of the birdwing mast in carbon fiber?" remains unanswered. The simple fact is that people have been building tapered and curved-edge wingspars in carbon fibre for decades. There's no reason why one needs to 3d print such a spar.

    Lots of knowledgeable well trained humans have already used modern powerful software and design facilities to design aerodynamic masts. They've been doing it for decades. You can read some of this information on line, should you choose to.

    Oh and yes, I was not there at the T200. You have not been racing with me when temperatures top the century. Despite what you said, people in such conditions do not have to stop moving. Whether you had to stop moving wasn't relevant anyway - what James was pointing out was not the issue of tacking downwind, but that sailing 101 says that you don't want to stop the wind flow.

    There has still not been a single piece of evidence, or any explanation using the abundant scientific and practical knowledge that is available, to indicate that the birdwing mast has any aerodynamic advantage over existing spars or that it has any potential advantage.

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    "There has still not been a single piece of evidence, or any explanation using the abundant scientific and practical knowledge that is available, to indicate that the birdwing mast has any aerodynamic advantage over existing spars or that it has any potential advantage."

    Thank you, that is exactly the point I'm trying to make. I would like to see some! I want higher aspect ratio birdwing masts made and in carbon fiber too! It's only fair that they use stays as well! I'm not at all afraid of the truth. Nobody knows what the "ultimate birdwing mast" can do until one is built and tested. The evidence in the case of the birdwing mast design is worth exploring. It presents a simple one-piece design with a very complex sickle shape. How aerodynamically slick it can become with computer optimization is unknown. It's like practical human powered flight. Just because it has yet to be achieved is a terrible excuse not to try at all.

    I've explained before how the sickle shaped mast can present balanced sail area with a single spar. I've explained how it can present curvature along the full length of the mast in the airflow. I've explained how the curvature of the mast can store well along the gunwale of the average boat. And by the way, a tall high aspect ratio birdwing mast can store very nicely along the gunwale of a long and skinny boat. I have a hunch about it being capable of some very low drag coefficient numbers when optimized with the latest technology and expertise. How advantageous that can be in a sickle shaped mast is also unknown. I will pursue ultimate birdwing mast research no matter what you say or do so if you want to waste your time, go for it dude!
    Last edited by kenjamin; 08-13-2017 at 10:57 AM.

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    If you want to see some theory to explore whether the birdwing could have any potential advantage then why not read some of the enormous amount of information that is available? Why not read Tom Speer's exploration of wingmast aerodynamics, for example?

    There are thousands of wingmasts that present curvature along the full length of the airflow. Plenty of us use them every weekend. The curvature is, in itself, of no advantage and those who respect the sailmakers and world champions who use such rigs know it. The practical advantage of "properly balanced sail area" have not been explained as you claim - you just keep on claiming that it exists.

    You mention human powered flight. The current leader in that area is MIT professor Mark Drela, who has also designed wingmasts. At no stage did he or Rutan or other people ignore the scientific knowledge that was available to them. If reading the available scientific knowledge in the area is good enough for Drela, Rutan and Wilbur Wright, why don't you?

    Anyway, if you're not going to bother to read what America's Cup winning aerodynamicists and MIT aerodynamic professors say about wingmasts, and if you think that "stopping the flow" is actually a good thing then it's obvious my time is indeed being wasted.

    I can't find the copy of the article by David Thomas in Yachting World magazine for around 1965 where I seem to recall him sketching a balanced wing mast with a curved leading edge. The article is called, I believe, "Now is the time to experiment" and deals with the upcoming IYRU singlehander trials. A later design for the trials, the dinghy Spy, used a cranked curved mast. There appears to be significant prior art in this area. Next time I'm in the right library I'll take another photocopy of the David Thomas piece and put it on the 'net, since it interests me for other reasons.

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    At the risk of self-promotion, the fact that I already have a U.S. patent on a design with at least twelve years of possible patent protection left on it so, selfishly, my main interest is building more prototypes and trying to improve on each and every one of them in order to add value to the patent. However, being an old retired guy who really enjoys being retired, I tend to not do anything that isn't fun to do during my retirement. I ride my bicycle, I photograph birds, I study birds, I do a little oil painting and I boat build but only when it is cool enough and the bugs are not bad. For me boatbuilding is only for late fall, winter and early spring.

    I appreciate that you want to add to the conversation regarding the birdwing mast. I want you to know that I do appreciate speed in sailing. I recently asked JF at Bedard Yacht Design how much it would cost for him to design me a 22' two person crewed, high aspect ratio, birdwinged ketch proa. He gave me an attractive estimate on such a boat and I hope to have it designed and build it someday. However, I have some unfinished business in Texas in regard to the Texas 200 that I would like to address first. It will be fun for me to bring Muri-Maru, my 17' 5" version of Captain Short's Yangtze Pelican, to real life rather than being content to just marvel at the 3D renderings of her by JF Bedard. I am very curious to know how well the overlap of the birdwing ketch sails translates into downwind performance even though you are not.



    I would love to somewhat spark interest in the research that I think needs to be done in regard to a top-notch, state-of-the-art fabricated, aerodynamically computer-optimized carbon fiber birdwing mast prototype with a computer created perfect taper to it. Such an animal will be expensive to create although a miniature one should be sufficient for testing especially since 3D printing is now available for such a complex shape. In the meantime, I will continue with my affordable spruce prototypes that lately are performing quite well for laminated spruce and they look pretty too which has got to count for something. In a way, the patent ties me down to it's definition because following its design is probably the one that is most potentially profitable for me. On the other hand, it's somewhat freeing in that the design part is already done, I just have to figure out how to optimize it virtually and build it physically in carbon fiber where its best performance potential lies.

    I will search for Tom Speer's exploration of wingmast aerodynamics as you suggest but it will not affect who I'm bringing to the research prom (so to speak), my patented birdwing mast design.

    Muri-Maru, my choice for dealing with the high winds, high humidity and high heat of the Texas 200:

    Last edited by kenjamin; 08-13-2017 at 08:31 PM.

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Quote Originally Posted by kenjamin View Post
    Guys don’t hate me but after giving it more thought, I misspoke with all those statements about “most” of my birdwing masts not really being birdwing masts. Much closer to the truth is that the expression “birdwing mast” actually applies more accurately to all of my prototypes rather than to the design described in U.S. patent #8,739,720.

    In a court of law it would soon be discovered that “birdwing mast” is actually the slang term that the inventor of U.S. patent #8,739,720 has been using to name all of his prototypes of his invention for the last ten years or so. As a matter of fact the term “birdwing mast” is never even mentioned anywhere in the language of U.S. patent #8,739,720. (More about this later)

    In regards to the guy in charge of the wind tunnel at FSU (at the time I wanted to use it), he was most certainly no aerodynamicist. He also most certainly was not a sailor either. He was a mechanical engineer but what he didn’t know about aerodynamics and sailboat mast construction, he more than made up for with arrogance. He thought that a strong central core was the way to go with soft lightweight add-ons to the central core to accommodate aerodynamic concerns. When I told him that was pretty much the opposite of the way sailboat masts were actually made, he started telling me about all his years of training and of course his doctorate degree in mechanical engineering. The funny part was that when I told him that he was not going to be redesigning my mast, he got so mad that he threw me out of his office saying that I did not respect his expertise enough and that was the one thing that he had gotten correct!

    Getting back to the definition of a birdwing mast, what I should have said is that most of my birdwing mast prototypes do not meet the aerodynamic description of a storable sickle-shaped sailboat mast as described in U.S. patent #8,739,20. It is only the last one or two of my prototypes that have utilized an “aerodynamically efficient” cross section along the curved part of their curved sections (and therefore might very well be able to meet the description of the invention found in U.S. patent #8,739,720).

    The point I was trying to make was that if a mast design is to have any chance of patent protection from U.S. patent #8,739,720, it would have to utilize an “aerodynamically efficient” cross section, an aerodynamically favorable, swept-back, over-all sickle shape and the ability to self-rotate to take best advantage of wind direction. So in addition to patent protection, it should also be good aerodynamically. That’s my opinion. I will leave all claims of aerodynamic efficiency to the company or corporation brave enough to test the design (at least virtually) and put it into commercial carbon fiber production. If I find that I can afford computer aerodynamic analysis of my design on my own, I will probably pursue that in the future in order to be able to show some evidence of aerodynamic efficiency.

    Sorry about the confusion, I should have given the subject more thought and chosen my words better.

    This is my latest birdwing mast prototype that I think has an "efficient" enough aerodynamically efficient cross section and could possibly qualify for patent protection under U.S. patent #8,739,720.





    This is the same mast stepped on my present boat in my front yard in St. Augustine, FL.
    Sounds like a lot of gobbledegook to me, and call me old fashioned but that has got to be the worst sail shape I've seen on an "efficient design" in quite some time
    whatever rocks your boat

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    I will add, you dont need a reason to muck around in boats and if a sickle is your thing then thats marvellous!
    whatever rocks your boat

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    As a profile template for a high aspect version of a sickle-shaped birdwing mast, there's something I really like about these Swallow-tailed Kite wings.



    Last edited by kenjamin; 08-14-2017 at 07:56 AM.

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Hmm. . .well, since you just won't bother to review or study the history of sailing technology at all, how about studying some aeronautical history at least? For example, what about the lovely Etrich Taube airplane of 1913?



    Here's a modern replica. What a beauty! Why don't they still make 'em that way?



    Oh, that's right, maybe because it was within just a few months completely outclassed and literally shot out of the skies by planes like this Morane Saulnier L with wings looking like this:



    And for some reason, as the war went on for the next couple of years and aviation tech progressed at a lightning rate, nobody seemed to want to go back to the utterly obvious aerodynamic awesomeness of that birdwingy shape. Weird, right? Those poor, know-nothing hacks. They musta wanted to get shot down with those terrible straight wings.

    Last edited by James McMullen; 08-14-2017 at 08:45 AM.

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    Default Re: Birdwing mast design to benefit from new sail track composite material

    Ugh! Trust a Belgian to resort to such shameful propaganda as this lying postcard of the era:


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