1/4 scale model

Discussion in 'Sailboats' started by Howlandwoodworks, Jun 11, 2019.

  1. Earl Boebert
    Joined: Dec 2005
    Posts: 370
    Likes: 45, Points: 28, Legacy Rep: 302
    Location: Albuquerque NM USA

    Earl Boebert Senior Member

    Yes. It's like the "stand off scale" idea in model airplanes. From twenty feet away your model looks like a P-38. Up close a P-38 expert can find a hundred things wrong with it: bigger elevator, wings forward, whatever you did to make it fly well.

    The average scale sailboat builder just wants to make a model that looks right and sails well. That's what John Black did with Yankee Jr. If you want to use the model to learn something about a proposed full-size boat, you're in a different problem domain.


  2. Howlandwoodworks
    Joined: Sep 2018
    Posts: 51
    Likes: 12, Points: 18
    Location: Columbia MO

    Howlandwoodworks John Howland

    I checked the center of buoyancy CB yesterday in a tank of water. It was on the water line.
    I though about putting a Dragon type keel on but if I build and can't sell it I will be sailing on inland lakes. The keels overall depth is a little deeper than an outboard motor. And finding boat ramps that will accommodate a deep keel are hard to find around here.
    I am going to fasten the keel and put some kind of transparent finish on the hull after grind off a bone headed idea I had. I add on to the keel making it proud from the hull, a division in between starboard and port, like a power boat. Well it's only a 1/4 scale mistake.

  3. Howlandwoodworks
    Joined: Sep 2018
    Posts: 51
    Likes: 12, Points: 18
    Location: Columbia MO

    Howlandwoodworks John Howland

    My first line above should have read.
    I checked the center of buoyancy with water yesterday, filed the hull with water to the water line and then took half out. Then with a dry bilge I set the 1/4 scale model in a tank of water, it sat on its waterline.
    I know that the VBC will take the Simpson's rule. I have the Table of Offsets in 8" sections in Excel now and have started to divide them into 2" sections of the below the waterline area for the Simpson's rule. After I have the COB I can start on the Dellenbaugh angle.
    I have acquired some of the easer numbers for my little boat such as the SA/D, D/LWL, BN, Sw, Aw, Ax, etc... There are a couple of pages of other numbers that I haven't acquired yet. After I calculator the more important numbers I will redesign the Wetted surface, keels root and tip of my little sailboat.
    Is this a viral or a mental issue that I have acquired about boats?
    Last edited: Sep 6, 2019
    Dolfiman and Doug Lord like this.
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