MPX-11 Very Small High Power Trimaran

Discussion in 'Multihulls' started by Doug Lord, Jul 13, 2010.

  1. Munter
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    Munter Amateur

    Doug - this is not so much a design in progress as an extended bout of self-delusion. You have no basis to make the claims that you repeatedly make and seem determined to ignore problems identified with your design. Harden up and acknowledge/fix the problems instead of denying their existence and you might have something called a design process. Until then you are just making bold claims based on imaginary performance.
     
  2. Gary Baigent
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    Gary Baigent Senior Member

    Doug, the amas just look wrong - and I'm not saying that because they look unlike any other ama designs around; keeping an open mind. If you want the lift and buoyancy well forward, why not angle the beams forward (and you could use one beam on this small tri, therefore saving weight) and shorten the ama length (less weight again). Also with he angled forward single beam you could run your flared cockpit, seat arrangement to link up with the beam - then you can put a track on the curve, killing two birds with one stone. With shortened amas you've got an immersed after foil; that will stop you worrying about pitching arse over backwards. The design is too fussy, needs to be simple. Just IMO. A 12 foot or so tri is really a model anyway - why not build it and try it out - easy enough to make changes, even radical ones on a tri that size.
     
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  3. Doug Lord
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    Doug Lord Flight Ready

    ==============
    Thanks for the comment Gary-but I disagree. I do agree about building it-seems like a good idea someday.
    PS-I want the static buoyancy aft a bit(compared to the planing lift) and the planing lift forward which is where it is. The lift from the planing hull is forward of the center of lift of the two hydrofoils and forward of the CG-as best I can tell it is in an ideal postion.
    In terms of surface area for low drag and light weight the ama hull is at the minimum where it can still work like it needs to.
     
  4. redreuben
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    redreuben redreuben

    Ha "someday" Doug Lord at his finest !
     
  5. cavalier mk2
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    cavalier mk2 Senior Member

    I think they will generate a lot of vortex drag, a smaller "wing" ? The shape is somewhat like a plow but intended to dig out not in. Why not fill up the bathtub and tow it around a bit as a early test, yes the scale/surface tension etc...is wrong but it might be a good early indicator. I like your suggestions Gary, very practical.
     
  6. cavalier mk2
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    cavalier mk2 Senior Member

    A farm plow also leaves a vortex of earth....I've watched them but around here we use tractors for the most part.....
     
  7. Eralnd44
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    Eralnd44 Wanderer

    tractors make down power with hydraulic. still must push down to dig dirt up.

    From search http://en.wikipedia.org/wiki/Plow

    "Modern ploughs
    Modern ploughs are usually multiple reversible ploughs, mounted on a tractor via a three-point linkage. These commonly have between two and as many as seven mouldboards – and semi-mounted ploughs (the lifting of which is supplemented by a wheel about half-way along their length) can have as many as eighteen mouldboards. The hydraulic system of the tractor is used to lift and reverse the implement, as well as to adjust furrow width and depth."

    ama for flashing tri digs down like plow as you say and keep with dig down until boat over on side. not good design also point shapes are the danger to sailor when tumbles. small boat to be fun and easy to make use. seat slaides pinch sailor legs and hand and also not good design. seat hard for build at factory unless great cost. small boat should cost little.

    flashing tri gets bigger every time. says first try not proper and comes to this talk before think time is done. claim at front of talk are big and boat also not done with think time says much about design. if also good why not build. if also easy for sailor why not build.
     
  8. Gary Baigent
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    Gary Baigent Senior Member

    Eraind44 - don't listen to Doug about your unique, descriptive and expressive English - it is a breath of fresh air ... and a distinct contrast to reading the usual boring cliches. Doug gets annoyed by criticism, although he must becoming immune to it by now, yet manfully plows on and on and on.
     
  9. Doug Lord
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    Doug Lord Flight Ready

    --------------
    I have NEVER made a comment about Eralnd44's language skills in any way whatsoever!!! I made a statement that, because of comments he made, that he might not have understood the concept, the theory behind it and/or the fact that it is a design in progress not a finished boat for which there is "proof"-not that he didn't understand the language I used. I'm convinced that he does not understand the concept-but the problem is NOT his language skills! There are numerous people for whom English is a first language, that don't understand the concept.
    As to criticism: I enjoy intelligent, well founded criticism but I have no patience for criticism that is embeded with a personal attack or presented with an ugly,offensive attitude or that shows that the material has not been read-I just ignore that kind of trash.
     
  10. Doug Lord
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    Doug Lord Flight Ready

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    1) I've done extensive work on the design of this thing so far and have backed up my work with comparisons to existing boats providing comparative ratios for several boats. I have many years of design, building and sailing experience and the numbers presented here back up my belief that this boat
    uses new technology on a small trimaran for the first time in history and that this new technology stands a real good chance of working. Only building and testing will PROVE that I'm right (or wrong) but at this stage the results are extremely encouraging.
    I completely disagree with your assertion that the "points" on the aft end of the ama present any danger whatsoever to a crew sailing this boat. I can't think of a single event that could bring the crew in contact with the aft end of the planing surface in any way that could cause injury.
    On this boat the shrouds aren't even in way of the crew! You mentioned someplace about the sliding seat injuring a crews hand: how could you possibly make a statement like that in good faith when I haven't even shown how that system will work!!! (see below)
    ---
    2) I never made any comment whatsoever about your ability to understand the English language-I think you do a great job! I don't think you understand this concept very well but it is not a language problem. I think that when you are willing to make a blanket statement like in 1 above your objectivity is seriously called in to question. See post:#59
    ---
    3) You spoke of arrogance earlier: this comment is the essence of arrogance.
    It is an obnoxious description of work that I care deeply about and I don't appreciate it one bit!


     
  11. Eralnd44
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    Eralnd44 Wanderer

    i see no points for aft on ama. i see large points for bow and is large danger for sailor when boat will crash. small boat will crash many times. flashing tri now large danger for sailor when made this way.

    i make hazard comment to sliding seat as model picture you show us. you say also it is slide seat when show the pictures . is person to think pictures and words are untruth. even simple zipper for pant is to catch important parts. sailor will find way to damage a body

    mr. doug lord i understand this boat. i work in technicle and mechanicle area. i also am owner of small trimran. i think you maybe do not understand own project as it is crazy with extra things to have no purpose. first make a simple boat. then maybe make one more thing as important. look to find new boat is to work good then can add more if also imortant. boat is to much now and not knowing of any result to make it good says is very hard to have all things correct. must start simple
     
  12. Doug Lord
    Joined: May 2009
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    Doug Lord Flight Ready

    =============
    1) are you talking about the skipper being hit by the bow?? If so I'm afraid you're way off base. See the pictures below-I know the guys that designed and built those boats and I personally have sailed the Rave many times and have never heard anything so preposterous as the crew being hit by the bow of an ama-much less by a knife sharp hydrofoil!
    --
    2) No, I don't think you do.
    --
    As I said earlier I appreciate well reasoned, informed constructive criticism and am modifying the model(and the design) now because of just such criticism that I became convinced was right. But #1 above is not like that....


    scary ama bows-with something coming up fast just behind them:
    (click on image)
     

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  13. Eralnd44
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    Eralnd44 Wanderer

    mr. doug

    pictures you show are with three foil boats that are different to flashing tri. you say boat is only with two foils to have tiny lift. talk is not same point. why use bad argument to making point.

    maybe you see picture from sailing anarchy with weta crash and sailor falling. is common on the small boats when gust comes as strong. sailor is now in water and boat moves around so wind and wave make it bounce.

    this happens to foil moth also so keep talk to point and not given away with small flick. you can see many photo of crashing moth on google

    sharp point on small boat on hard condition is dangerous. sharp point should not be on small craft and to make so is bad design. this flashing tri is not good design. truth is worse when children is who would be sailor.

    find other way to solve problem before to drive big hole in young sailor. words you say now are good food for lawyer that is maybe soon to visit.
     

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  14. Munter
    Joined: Jul 2007
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    Munter Amateur

    Eralnd - fear not. The safety factor in Doug's design is that it will never be built so the risk to real living humans is very low (presuming you can resist the strong urge that this thread gives sane readers, to poke a pencil in their eye).
     

  15. Paul B

    Paul B Previous Member

    You would not ask this question if you have read about all the great "designs" by The Lord of All Foiling and Canting over the past 8 years or so.
     
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