Propeller Cocnulation for power boat.

Discussion in 'Powerboats' started by Touralis, Jun 30, 2013.

  1. Touralis
    Joined: Jun 2013
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    Location: Greece

    Touralis Junior Member

    Hello, i have a boat 10 meters long, 7 meters in the water with 2 meters 30 with,depth 40 santemeters, made out of aluminium. The weight of the boad fully loaded is 2000kilos. I have yanmar 315 horsepower,3800 rpm.I have custom surface drive non trinable,the prop of transom is 75 santemetres and the length of shaft is 1.10m . Thickness of axon is 50mm. Please let me know what size of the propella i need,gearation and how long the delivery from the day of order, the prize,and also the maximum speed of the boat.
    With regards Toyralis.
     
  2. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    The weight of the engine without gears is 408 kg. If you add the gears, drive, fuel and crew, there is no way the boat can be 2000 kg fully loaded. Also, it is very underpowered. If this is a boat that is already built, you should weigh the boat and then make proper calculations. What are you trying to accomplish with this kind of setup with so little power?
     
  3. Touralis
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    Touralis Junior Member

    .

    Good evening..It's has been caclulated 2 times and its 2000 kilos..what the performance u belieave will be?
     
  4. gonzo
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    gonzo Senior Member

    I think you have this and another thread asking for surface propeller calculations. I believe your calculation is very wrong. Please post your weights to justify the claim of 2000 kg.
     
  5. Touralis
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    Touralis Junior Member

    with passengers is 2.200kg
     
  6. gonzo
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    gonzo Senior Member

    Can you give the breakdown of weights? That is the spreadsheet where the weight of everything is included and then added up. You will see that there are many things either missing or not calculated properly. The fuel and machinery is at least 1000 kg. When you make a claim of "fully loaded", that includes crew and everything else that may have to be onboard, including safety gear.
     
  7. Touralis
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    Touralis Junior Member

    2367 kilos is the final weight of the boat.
     

  8. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    Touralis: Unless you can justify that, it is just a random number. Can you post your calculations?
     
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