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  1. #1
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    Villain 1V - One motor > Twin outdrives !

    A little background first

    As we all know a stock villain uses 2 brushed motors, each powering a steerable outdrive. Many mods include either replacing the brushed with brushless - been there done that, it was VERY quick, too quick infact, and needed LOTS of water to get the best out of it, even then it became unstable at speed, and I have the distinction of flipping my Villain on flat water - must learn not to turn quickly at high speed!

    Other mods include stripping out all the stock drive stuff and replacing it with a single brushless driving a single prop, yes it makes a fast boat, but for me thats not a Villain - just a fast deep V.

    One of the characteristics of a Villain is the twin steerable outdrives, so how else can you mod it without upgrading either the brushd motors or creating a 'monster' with twin brushless - how about a gearbox and ONE motor driving the stock TWIN steerable outdrives !

    Based on many assumptions such as a brushed runs at about 20,000 RPM, and in a Villain is geared down 2:1 so a theoretical prop speed out of the water is about 10,000 rpm (these are guesstimates by the way), so in the water (under load) the actual prop speed is going to be less than 10,000 rpm, lets assume 7000 rpm for now. To get more speed. you need to either turn the props (in wate so under load) more than my theoretical 7000 rpm, or get motors to turn bigger props at 7000 rpm or more.

    Hence my idea of a single high torque brushless, (I used an eMax 960KV) coupled to a series of gears which would give 1:1 gearing and counter rotating props, in theory 960kv x 14.4v = 13824 RPM no load, and perhaps about 10,000 RPM in the water?

    It worked well, too much torque infact, what you don't see in the video is the on the spot repairs where it stripped a few grubscrews off the gear shafts, so I am going to dissassemble it and tap out the gears to take M4 grub screws, and I also want to try out bigger props - did I mention the test run in the video is using Villain stock props !

    Here is the gearbox :


    Here is a video of the boats first run :

    http://www.youtube.com/watch?v=hrR1tpfB7-U

    I am rather pleased with it, especially the neat bit of parking at the end
    Last edited by floaty; 08-25-2010 at 04:40 PM. Reason: typo's LOL

  2. #2
    Traxxas Marshal
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    That is brilliant! I love it! It looks as though it runs very well, too. Nice work... and nice docking at the end!

    Happy boating,


    -cooleo
    "Happiness depends upon ourselves." -Aristotle

  3. #3
    RC Champion
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    1,121
    thats the exact set up ive been thinking about! looks great, good job!
    I was anti-obama before it was cool!

  4. #4
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    ..................thanks,

    I used two x MOD 1 30 tooth gears, and three x MOD 1 20 tooth gears to give 1:1 counter rotating. Left and right shafts need to be 55mm apart which is your starting point, and the other shafts (all 4mm dia) have to be carefully positioned so you are not too tight (or loose) on the gears, then once done, make the motor mount so its shaft is inline with your center shaft - and it should work OK.

    As I have found, if not quite in line, it causes a little vibration, which loosens grub screws so you loose drive, or as I am thinking of doing - shorten the prop tubes (to bring the gearbox and motor more towards the stern) and use a short flex drive from the motor to the gearbox, so it doesn't matter too much if its not all lined up 100%, and it will help on start up also, as there is lots of initial torque.

    Also, you will notice the prop shafts extend beyond the back of the gearbox - thats so I can add back twin brushless, and just disconnect the center drive, so I have a choice of which motors to run, using twin brushless makes it VERY quick, too quick for a small lake LOL (I flipped mine a couple of times on flat water using twin brushless!)
    Last edited by floaty; 09-02-2010 at 02:30 AM.

  5. #5
    RC Qualifier
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    Apr 2010
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    top work, well done
    erevo, ubuntu.com

  6. #6
    RC Champion
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    Very cool. Excellant job!
    Land of the free?

  7. #7
    RC Racer
    Join Date
    Oct 2008
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    104
    Is the gearbox something you have buildt or something that one can buy, because it looks great!
    Powerhouse Sweden
    Villain IV with Octura 447

  8. #8
    RC poster
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    Jul 2010
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    Quote Originally Posted by Powerhouse View Post
    Is the gearbox something you have buildt or something that one can buy, because it looks great!
    ...................thanks, the gearbox was built from scratch, took a few attempts to get it right though

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