Planing Float Keel Design?

Discussion in 'Boat Design' started by BulBob, Dec 30, 2005.

  1. BulBob
    Joined: Dec 2005
    Posts: 34
    Likes: 1, Points: 0, Legacy Rep: 17
    Location: Norton, OH 44203

    BulBob Paul

    I invented the BulletBobber but could use some help with design improvements. To see the ones I'm making now go to www.bulletbobber.com and watch the video and note the shape. The one problem I have with the present design is that they will dive. I would like to make the keel more stream lined.
    I am considering making changes to the design as shown below.

    Does anyone have any comments or suggestions from observations? need more info?

    Thanks
     

    Attached Files:

  2. Deering
    Joined: Feb 2005
    Posts: 481
    Likes: 25, Points: 18, Legacy Rep: 44
    Location: Juneau, Alaska

    Deering Senior Member

    Cool little device!

    Hard to tell from the videos what's going on, but two ideas that maybe would help:

    Where the line exits the bobber (on the hook end) rather than having a tube running through the bobber, why not a vertical slot? The downward force of the line would be lower on the 'hull' and not cause quite so much 'heeling' force. Maybe squash one end of the through tube to produce the slot.

    Second idea - angle the through tube back so the exit end (hook side) is located about amidships - that should center the downward force a bit more rather than pulling the 'bow' downwards.

    Hope that makes sense - if you use my ideas successfully I expect to receive 5 bobbers as payment!
     
  3. Kiteship
    Joined: May 2004
    Posts: 143
    Likes: 7, Points: 0, Legacy Rep: 81
    Location: SF Bay area

    Kiteship Senior Member

    This one is very interesting to me; not as a fishing lure (though that's certainly where the money is!), but as a "hapa" for creating side force for sailboats. You may know hapas; they are "underwater kites" which have been proposed as replacements for keels on sailboats. the thing is, nobody has yet built one which will reliably run on both tacks...

    Unfortunately, the best info on hapas isn't available on the internet--consider buying "Ultimate Sailboats" I through IV and also "Transport Sailcraft", all from the Amateur Yacht Research Society. These originally sold at about UK 5 pounds apiece, but you should be able to get all 5 of them for 10-12 UK pounds, these days (maybe even less if you'll join AYRS--I'm a director, you see!) www.ayrs.org.

    Why will your change prevent diving? It will make the device asymetrical, on either tack. What effect will this have? Please explain to us whether Deering's ideas will work or not--and why? May I have access to your patent, or are you holding that to yourself for now?

    Thanks,

    Dave Culp
     

  4. BulBob
    Joined: Dec 2005
    Posts: 34
    Likes: 1, Points: 0, Legacy Rep: 17
    Location: Norton, OH 44203

    BulBob Paul

    More Info

    The opening where the line goes in is set to get the widest planing angle.
    The opening where the line comes out is then established to make it flip when given a little tug.
    The front is taller now to provide more buoyancy and hopefully prevent diving.
    The 2 halves must be opposites to flip and plane one way as well as the other.
    The keel was hollow but I'm making it solid/thinner so it is more stream lined.
    My main question is what shape keel would work the best.
    The specific gravity of the plastic is the same as water and it needs to be at least half out of the water to work.
    There is 50% more air space volume inside then total plastic volume.
    I do not know if this design will flip and will need yet another SLA made to test it.

    I got a utility patent because there are 250 million bobbers sold each year in the US.
    There are only about 10 bobber manufacturers and over a100 lure makers.
    Making a line of fishing lures is my next project.
     

    Attached Files:

    Last edited: Jan 1, 2006
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