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Conference vmszoo::rc

Title:Welcome To The Radio Control Conference
Notice:dir's in 11, who's who in 4, sales in 6, auctions 19
Moderator:VMSSG::FRIEDRICHS
Created:Tue Jan 13 1987
Last Modified:Thu Jun 05 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:1706
Total number of notes:27193

1279.0. "Some boat questions" by DEPOT::BROWN () Wed Jan 02 1991 14:16

    My first question is:  Is it possible to use a liquid fuel engine
    			   in a plastic hull? The engine would be enclosed
    			   by the hull and deck with some ventilation.
    
    Second question is:  I've seen one electric motor driving two screws,
    			 is this possible for a liquid fuel motor at high
    			 RPM's?
    
    -Kendall
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1279.1Yes and yes...BTOVT::VTLAKE::WHITE_RWed Jan 02 1991 15:256
    The answer to both questions is yes.  Use a liquid (water) cooled
    engine and you can fully enclose it in a plastic hull with no problem.
    With the proper gearing you can turn two or more screws with one
    engine.  I've seen a K&B 7.5 turn 3 with no problem.  Hope this helps.
    
    Robert
1279.2DEPOT::BROWNWed Jan 02 1991 16:436
    
    Thank you for the reply Robert, thats just what I wanted to hear.
    What (roughly) would be the expected speed out of a V hull that fully
    loaded weighed 3-5 lbs. with whatever motor?
    
    -Kendall
1279.3Depends upon the whatever...BTOVT::VTLAKE::WHITE_RThu Jan 03 1991 15:556
    The whatever motor will determine your top speed.  The 7.5 K&B was
    salvaged from a V hull that weighed 4 1/2 lbs. before it sank after
    hitting the dock at about 13 knots (and she wasn't full throttle
    according to the captain).
    
    Robert
1279.4AMTRAK::BROWNThu Jan 03 1991 18:3910
    
    Thanks for the information Robert.  I'm sending off for a Tower catalog
    to browse through for specs and prices.  I'm making a scale patrol
    boat, it was originally the PT109 but I have made too many
    modifications to call it that now.  The liquid cooled gas motor is just
    what I was looking for, fast with endurance.
    
    I can't wait for spring time to come along for the maiden voyage!
    
    -Kendall
1279.5DEPOT::BROWNFri Jan 04 1991 11:447
    
    Ok, one more question....for now ;-)  I want to conceal my antenna by
    wrapping it up and around the mast head/radar tower that I installed
    on the boat.  Is this ok to do and can the antenna be too long?  I
    guess that's two questions!
    
    -Kendall
1279.6Yes and No...BTOVT::VTLAKE::WHITE_RFri Jan 04 1991 15:1410
    Whatever you do, DO NOT CUT your antennae or else your maiden voyage
    could also turn out to be your last voyage.  It's recommended to
    extend your antennae as much as possible, but some people coil there
    antennaes around a piece of cardboard and extend only a portion.  This
    works well in cars for racing.  But in a plane or boat or any object
    that you plan to run a good distance from you, I would not recommend
    this.  Maybe somebody else out there can provide more input to
    disguising an antennae to add to the model's realism.  Hope this helps.
    
    Robert
1279.7This workedGRANMA::WFIGANIAKYEAH..GET THE RED ONETue Jan 08 1991 12:273
    Try running the antenna wire around the inside of the hull just below
    the deck. I did this on a model Wellcraft and it worked out just fine.
    Good luck
1279.8Motor size?MINDER::SWCA06::HESLOPThu Sep 19 1991 10:498
    I'm planning to put an IC engine in a 36" glassfibre V hull I have. The
    recommendations from the local hobby shops vary from a .40 glow to a
    .61 glow motor.
    Any comments on the motor sizes? Expected performance? What sort of
    fuel consumption so I can decide on tank size?
    
    Brian
    
1279.9PFSVAX::MATSCHERZTue Sep 24 1991 14:2015
    re.-.1 
    
     Any motor in the .40 to .6X range will give you more than adequate
    performance. I have a .45 on a hydroplane (30 inches in length), and
    will say that it you put too much motor on it, the back end of the boat
    will pop up out of the water. I have heard of hydros running .65 K&Bs
    going about 60mph or so. I would go with a 8 oz tank, that should give
    you about a 20 min. run. 
      You will have some other concerns to address as well; you must keep
    the water out of the flywheel area, also fresh air and exhaust must be
    dealt with. I had more problems dealing with these things than the
    actual installation of motor and servo setups.
    
    
    			Steve M..