Ideal Drag disk radius

Discussion in 'Propulsion' started by tgalx3, Jun 5, 2024.

  1. Anvil_x

    Anvil_x Well-Known Member

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    good!!!
     
  2. bsgkid117

    bsgkid117 Vendor

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    I would weight the stern slightly, what are you running at total weight wise? Generally cavitation on a large ship is because it's too light, but I also have no idea what weight youre at.
     
  3. Anvil_x

    Anvil_x Well-Known Member

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    yeah that's a good point @bsgkid117 . I didn't notice any cavitation with my boat during the blade count testing and it was likely due a lot to proper ballasting, especially considering how Nate G. had so much trouble with his WeeVee and cavitation at scale waterline
     
  4. tgalx3

    tgalx3 Well-Known Member

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    im running at 40lbs. When I say cavitation i meant the 2.25” drag props were causing just enough wake to not allow enough water to reach the prop.

    I was also a bit bow heavy today because the change in drive motor size threw off my trim.
     
  5. bsgkid117

    bsgkid117 Vendor

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    There's A lot of fine-tuning that can be done here. It's up to you to figure out how far down this rabbit hole you want to go. You definitely don't want to be nose heavy that will make any cavitation a lot worse. 40 lb is definitely not bad for a Bismarck. You can cut the discs to create a D shape if that would aid in flow to the main prop. Or cut them so that way you can move them farther forward away from the drive prop.
     
  6. tgalx3

    tgalx3 Well-Known Member

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    I can cut them into a "D" shape? I interpreted the rules to be that they had to circular disks.
     
  7. SnipeHunter

    SnipeHunter Well-Known Member

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    Yes, they have to be circular but then you're allowed one flat cut.
     
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  8. tgalx3

    tgalx3 Well-Known Member

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    cool. I didn't realize that.