Cowl vent patterns?

Discussion in 'Ship & Watercraft Models' started by OhioMike, Aug 20, 2007.

  1. OhioMike

    OhioMike Member

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    I wonder if someone could help me with a pattern that i could resize of a cowl vent? The curves of these things have me all screwed up! Thanks in advance.
    Mike:cry:
  2. Stev0

    Stev0 Active Member

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    Like slats stamped into steel that allow warm air to escape????

    I need a little more info on this ... pics could help.
  3. OhioMike

    OhioMike Member

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    No, the classic ship board deck vents. Like these.:cool:

    Attached Files:

  4. Stev0

    Stev0 Active Member

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    I would say cheat.

    - Get a drinking straw of like size.
    - Flare one end of the straw to match the bell shape.
    - Cut a V shaped section from the side out of it but make sure there is enough straw left to retain it's shape and not splay open.
    - Fold the straw at the cut apex and glue with crazy glue.

    I think this would only work with VERY small scaled vents.

    The narrower the V cuts and the more you have to complete the 90* angle the smoother the curve.

    [​IMG]

    I'm not a ship modeller but it's how I would do it. Plastic straw could be substituted for paper if you create the cylinder from paper first.
  5. dansls1

    dansls1 Member

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    The air intake on the BF109-G8 I'm building right now is very similar to this - and if you imagine the step 3 piece cut on the right side and laid out flat that's the design they use.
  6. Bernhard

    Bernhard Member

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    Hi Ohio Mike
    The curves of these things are compound curves and cannot be unrolled in a geometrically exact way - no matter how hard you try.
    You can only approximate the shape. A coarse approximation results in few parts which can be easily assembled. A close approximation requires a large number of parts which may be difficult to glue together.
    It depends a little bit on how small a vent you want to build and how simple a shape you find acceptable.
    What size of vent do you need?
    I designed two patterns in Rhino one simple (3 parts) for small vents and a more complicated one (5 parts, if memory serves me right) for vents with an opening of about 1cm (and more).

    Bernhard