4 Meter mono foiler project

Discussion in 'Sailboats' started by wind_apparent, Apr 27, 2008.

  1. wind_apparent
    Joined: Apr 2008
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    Location: boulder colorado

    wind_apparent wind driven speed addict

    I knew Sailing anarchy would screw me, who would have known it would be by going offline for a couple of days sending people to my thread to act like 5th graders. (but it has been great fun, and I see it going back to boat building as usual in the near future)

    Chris, can I get a pair of your foiling teva's (10.5 + gantry, or if your going for a longer no gantry design I'll take an 11) :D

    ****It seems like SA's server is working again, see you all there. :p
  2. Paul B

    Paul B Previous Member

    Just like you were going to have a foiling 20 foot sportboat available to race and beat a modified 18 footer 4 or 5 years ago?

    Time to pony up people. I will put up $100.00 US hard cash (yes, worthless around the world) against the first person who will take the Doug Lord vs WA in the following contest:

    First person to complete their foiler design/build and prove they can foil on it for 200 meters without dropping back off.

    I've never met either person, I'm taking WA, and I will immediately send my money to a 3rd party to hold if anyone takes this challenge within the next week.
  3. foilman24
    Joined: Aug 2008
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    Location: home

    foilman24 Junior Member

    This could get interesting. good luck finding someone that dumb. :D (i think you might want to stipulate the boat being full size and sailed by the builder, so No models, and no ringer helms.)
  4. Doug Halsey
    Joined: Feb 2007
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    Location: California, USA

    Doug Halsey Senior Member


    Since we're already way off topic, I can't resist pointing out that the "bouyancy pods" on your monofoiler have more volume than the amas on my trimaran.
  5. wind_apparent
    Joined: Apr 2008
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    Location: boulder colorado

    wind_apparent wind driven speed addict

    Back to the main topic.


    So I've been fairly productive here on the computer today, spent the morning making the Sr-71 blog, so here it is, (so you can all stop PMing me asking when its going online :p) it's not anything you haven't seen before but stop by and have a look. Feel free to subscribe. It would be great to see my Boatdesign.net friends on there every once in a while ;). I will still be posting here on my thread so I can still get some "Interaction", but thought it would be good to have a proper blog as well. (it will be a lot easier to keep on topic :p )

  6. Doug Lord

    Doug Lord Guest

    Really? Doesn't look like it to me. But those pods are bigger than the final version though the beauty of removable pods is that they
    can be changed to any volume that does the job for the individual skipper.
    Also:"5) Buoyancy pods approx 1.56 cu' per side; larger optional pods available for training.(see approx 3 cu. ft. pods illustrated in the sketches in post #15)"

    Great blog Sam!

    Kotaro Horiuchi's bi-foiler: (multihull version)

    Attached Files:

  7. Paul B

    Paul B Previous Member

    I doubt anyone will jump in, especially considering the **** **** himself has not, even though he has been on the site again posting photos of a boat he didn't design. I guess that means we won't see his pile-o'-parts assembled and foiling before next summer. I would guess it will be a LOT longer than that.

    I would have bet $10K on this, but some smart guy would have taken it on himself to actually design and build the thing for ******, then with a few weeks to coach him (hopefully it wouldn't take longer than that) on how to sail the thing the smart guy would have his own foiler paid for with my wager.
  8. wind_apparent
    Joined: Apr 2008
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    Location: boulder colorado

    wind_apparent wind driven speed addict

    MDF dust

    Well, I finally got around to working on something today. During my lunch break I found some time to get over to our woodshop to finish cutting all support frames for my moulds (Thanks to Scott Murphy for all his help). I'm using a mould building technique I adapted from Bill Beaver, Its a braced and framed MDF mould with slotted L brackets on the outside to hold all the stanchions in place, and a T bracket strongback to hold them down the middle), I hope to get those glued up tomorrow, and who knows, maybe have pics. As far as hull construction goes, I'm making a ply skinned male mould that I can vac press to. I also have a foredeck mould and a deck mould in the works. Can't wait to get back to it, See you tomorrow...... (I might have some foil pics as well, I'm thinking of just using some standard foils from Ardvarkracing, Mike is suppose to send some pics of the new foils he's building, if he does I'll post em)
  9. Doug Lord

    Doug Lord Guest

    Would they be the standard Moth foils he makes? If so not a good idea. Any way he can increase the area?
  10. wind_apparent
    Joined: Apr 2008
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    Location: boulder colorado

    wind_apparent wind driven speed addict

    Mike is sending me the pics of the new moth foils, then if I like the build quality I was hoping to discuss with him the possibility of designing some for me based off them but with a larger lift area for this project. Then I would just take the drawings and make my own mold to build some here at home.

    MAIN = .1m2
    RUDDER = .75m2

    I want to see what he thinks would be a good extra amount to add given his design specs.

    we'll see what they look like.
  11. Doug Lord

    Doug Lord Guest

    Good plan.
  12. Doug Lord

    Doug Lord Guest

    Foil Loading

    A) Based on a vealmoth(66+154=220lb.all up):
    1) moth mainfoil area you posted=1.076 sq.ft.. Foil loading (at 220 X .8=176lb)
    with the main foil supporting 80% of the load=(176/1.076)=163.6lb per sq. ft..
    2) early Ilett foil that I have=1.19 sq.ft.. Foil loading@ 80%=147.9 lb. per sq. ft.
    B) Your boat (90lb ready to sail+ 190 crew=280lb ):
    1) Foil area based on 163.6lb Moth loading:280 X .8=224; 224/163.6=1.35 sq.ft. mainfoil area.
    2) Foil area based on 147.9lb Moth(Ilett) loading: 224/147.9=1.51 sq. ft. main foil area.
    =============== ========
    I'd suggest trying to get the exact Bladerider and Prowler Zero foil areas and go with the one with lower loading and convert to your weight as above. Maybe Bora would help with that.
    As per my PM read this-you WILL get a kick out of it: This is from the Aussie Moth forum under "hydrofoils", page 2 "hydrofoil options". Same bs.
    Famous Phil S quote: "So I see the proposed 50kg narrow International Canoe without foils as the best option for those people who are too big to race a foiling moth. Foils would not work well enough in a wide range of winds." yeah,right!
  13. wind_apparent
    Joined: Apr 2008
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    Location: boulder colorado

    wind_apparent wind driven speed addict

    yup, about the same number I came up with, but I used 185 skipper weight, (actually 1.3594 but after rounding its pretty much the same)

    I will ask Bora, but I don't know, when I asked him about midship wands a while ago he just laughed at me. :D
  14. Doug Lord

    Doug Lord Guest

    midship wand

    For Gods sake don't even consider a midship wand wand! That is just a ridiculous fantasy some non-foiler dreamed up while out of his head-its pure rubbish-ask SimonN, Phil S and many other champions of the highest tech in the Moth class.
    In fact, I bet "Paul B" could tell you how terrible such a wand is. Or maybe Bistros,or Chris Ostlind,or........

  15. bistros

    bistros Previous Member

    I'm betting they look like a couple upside down capital letter T's. Some people use an upside down lower case "t" for the rudder foil.

    Increasing the font size of your "T's" provides more lift for your foiler!


    I've indicated clearly in this thread that Wind Apparent should research his own control systems, and make his own informed decisions. I pointed out that the largest body of evidence to date indicated a bow wand may possibly be of benefit. I also clearly indicated the technology was in it's infancy and other options may prove to be of value. If you were objective you would take the same position, unless you were prepared to create a test environment, run sufficient experiments to collect a body of evidence and prove or disprove your theories.

    Certainly, the largest collection of data and testing to date has been done by Fastacraft and Bladerider - not only experimental testing, but volume production use of the wands in racing environments up to and including Worlds level. If you wished to truly contest their conclusions, you should build/buy a Moth, configure it with a wand of your design, and race it competitively over a couple seasons. If you are right the truth will be known. I have no dogs in this hunt, so I'd be just as happy if your theories were proven right and everyone else wrong.
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