Graf Spee Motors

Discussion in 'Propulsion' started by tgalx3, Jun 20, 2022.

  1. tgalx3

    tgalx3 Well-Known Member

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    I’ve never built a ship this small what kind/size of motors are recommended for the drive and ideally the pump?
     
    Last edited: Jun 21, 2022
  2. Boatmeister

    Boatmeister Active Member

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    550's are are the best all around motors, but twin 380's would work if you're battling big gun. Depends on your internal layout
     
  3. tgalx3

    tgalx3 Well-Known Member

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    Yea I'm building 1/144. So I would do two 550s then.

    On my old Bismarck I had a single giant motor(don't remember the size) so I would do 3 smaller motors instead? Also, am I correct in understanding that the rules say the Bismarck would need a drag disk?
     
  4. darkapollo

    darkapollo Well-Known Member

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    It depends on the rule set. Fast gun, you would just need to have a dummy prop or drag disk for each unpowered shaft.
     
  5. Bob

    Bob Well-Known Member

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    What size props are you using. For 1.25” a 390 motor works well direct drive. For 1.5” and larger a geared system with 550 works well. Or there are also lots of brushless choices.
    On my Graf Spee I used 550 and a gear box.
     
  6. tgalx3

    tgalx3 Well-Known Member

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    Im not opposed to gear boxes. I do like direct drives better.
     
  7. Bob

    Bob Well-Known Member

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    Gear boxes make a huge difference in your acceleration and deceleration. Once you get into a ship that’s more that 10lbs you really should use them.
     
  8. tgalx3

    tgalx3 Well-Known Member

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    How do gear boxes help acceleration and deceleration?
     
  9. Commodore

    Commodore Well-Known Member

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    Think of it like your car. Imagine if you didn't have 1st, 2nd or 3rd gear, but only 4th +. Accelerating from a stop would be kind of hard, right?
    Electric motors are happiest at higher RPMs. Props are happiest at lower RPMs. Gearboxes give you the best efficiency, and low end torque for when the light turns green.