Sunday 29 April 2012

Nitro RC Cars


RC Basics - Start Here!

Congratulations on taking your first step into the exhilarating hobby of R/C!
By now you basically know that there are five major types of RC vehicles:
  • Airplanes
  • Helicopters
  • Boats
  • Cars
  • Trucks
All of them have one thing in common: they are all controlled by a transmitter that sends a series of signals to a receiver located in the vehicle. The receiver then sends the commands it receives from the transmitter to the servos or electronic speed controller.
This is referred to as the Radio System.
A servo is a little electric motor that rotates a few degrees in each direction. Attached to the servo is the servo arm (also known as horn). The linkage arm then connects to the linkage, which is then attached to whatever part of the vehicle it is assigned to control.
From left to right: 4 Channel Transmitter, 4 Channel Receiver, Servo, 2 Channel Transmitter.
Futaba Radio System
For instance, a linkage can be attached to a servo arm at one end and to the tiller of the rudder on the other end. Servos can control the flaps on an airplane wing, or the throttle of a nitro Monster Truck.
Electric motors are not controlled by the physical motion of a servo. In this case, they are controlled by an Electronic Speed Control (ESC) which controls electronically the amount of power a motor receives:
electronic speed control
The more functions required of the vehicle the more channels there are.
For instance, most radio controlled power boats only really need two channels, one for moving the rudder and one for the throttle. The same goes for RC cars and RC trucks, although some of the really big RC cars also use a third channel and servo for their braking system, like the H.A.R.M. 1/5th Scale Gasoline RC Cars.
Radio controlled airplanes typically use 3 to 4 channels, and RC helicopters can use up to 9 channels!
IMPORTANT Final Note on Radio Systems:
With ALL RC vehicles, when getting ready to begin use, the transmitter must ALWAYS be turned on before the receiver. To operate correctly, the receiver MUST be able to sync up with the transmitter immediately.
If this is procedure is not followed, then the receiver may cause the vehicle to run amok since there are no commands controlling it!
Even turning the transmitter on immediately after the receiver is turned on is NOT going to be effective.

Power On!
Now that we know what controls the RC vehicle, let's talk about what actually makes it move!
Power is provided either from an electric motor or from a combustion engine:
  • Electric motors run on rechargeable batteries that come in all different sizes based on the specifications of the motor. These are often referred to as "power packs".


  • Combustion engines run on either Nitro Fuel or Gasoline (usually only for the biggest RC vehicles).

    epic motor
    You should also note that both the transmitter and the receiver pack are powered by batteries. In most cases they will require AA batteries but in some electric models, like the Hangar 9 Aspire Glider, the receiver pack and servos are also powered by the same rechargeable battery that powers the motor (for launching purposes only - prop folds when desired altitude is reached).



    hangar 9 aspire

    When selecting your first RC vehicle always keep in mind that a power support package is always going to be needed. For the electric versions you'll need the batteries and charger. For the nitro versions you'll need the fuel, a glow plug ignitor, wrench, and other accessories. Some vehicles come with everything included.
    It's always important to check and see if any additional items are required to operate the vehicle when you buy it. This way you won't be running to the store for any last minute items you thought were included.




    IMPORTANT - a brief note about Electric Powered Vehicles:
    I always recommend to my customers that they purchase more than one rechargeable battery even if one is already included with the vehicle.
    This way when the first battery runs down from use, you can take it out, put it on the charger, and attached the second fully charged battery and get back to the action.
    It sure beats waiting and watching every 30 seconds for the battery recharger light to blink green!
    Also: it's always a good idea to keep an oven mitt handy to put the batteries on it while they're being recharged. The nature of recharging is a chemical reaction and heat is always created. It's normal for batteries to get hot when charging and also immediately after use.
    In some rare cases batteries have been known to get extremely hot and actually swell up in size (they cannot be used after this occurs).
    So PLEASE never leave a battery unattended for too long while it's charging. This is a very important safetly warning.
    Battery Strength: you should also know that most of the rechargeable batteries (except LiPo's) used for RC need to be cycled two to three times before they reach their maximum power output.
    This means that you will need to charge them and discharge them three times prior to use. To discharge a battery put it in your vehicle and let it run on a slow speed until the motor stops. For RC airplanes I put them on my workbench and hook a right angle in front of the tail elevator. Then I simply move the throttle toggle into the slowest position to make the prop spin. In 15 minutes the battery has fully run down. I give it 10 minutes to cool down and then I put it back on the charger.
    For RC Car and Trucks, do the same thing but put a shoebox under them so they remain stationary.
    Boats are a little bit tougher since the motors typically need to be water cooled. As long as you remove the top deck and keep the motor(s) exposed, and run them at their slowest speeds, you should be fine.
    If you're willing to make the investment, there are some battery chargers that also have discharge features.


    Megatech juicebox 2
    Battery Chargers get their power one of two ways: from an AC wall outlet, or from your car battery. They can connect to your car battery either with a power socket adapter (cigarette lighter opening), or with two big clips directly on the car battery. some battery chargers come with all of these options while others have only one.
    So make sure you which one you're getting in order to best plan how, where, and when you'll be able to charge your batteries!




    IMPORTANT - a brief note about Nitro Powered Vehicles:
    Nitro powered vehicles require a special type of fuel. This complete name is nitro methane and they come in different percentages of concentration with different amounts of natural castor oil and synthetic oil mixed in. The most common types range from 15% to 30% nitro methane.
    RC Nitro Fuel is made up of three ingredients:

    • Methanol (alcohol)
    • Synthetic and non-Synthetic (Castor) Oil (usually 11% of mixture is oil combination)
    • Nitro Methane

    The percentage listed is the amount of Nitro Methane, so 20% would mean that there is 20% Nitro Methane, 11% Oil, and 69% Methanol.
    There are different blends for different uses:
    The 20% blends are formulated specifically for 1/10th scale racing and the 30% blends are for 1/8th scale.
    The Platinum Blends include more oil for prolonged engine protection. This is a must if you are racing your engine frequently throughout the day!
    The 15% blends are used almost exclusively for RC Helicopters and RC Airplanes. This blend has a higher amount of oil in the mixture since these engines are run at near full throttle the majority of the time.
    You should also note that there are differences in fuel brands based on these blends and also on whether they were refined domestically or at a non - U.S. facility.
    Domestic blends are better and here's why: in order to ship nitro fuel to the U.S., foreign manufacturers have to add tri-ethylene as a moisture and combustion prohibitor since this is consider a hazardous material. The engine then needs to reach a hotter temperature for combustion to occur. The hotter the engine runs, the shorter it's life.



    Nitro Accessories
    In addition to needing nitro fuel to run your vehicle, you will also need a few essential tools. These include:

    • Glow Plug Ignitor - used to start the nitro engine
    • Glow Plug Wrench - used to tighten or loosen the glow plug and other nuts
    • After Run Oil - put into the engine cylinder at the end of the day's running to protect it from corrosion
    • Fuel Bottle - for easy fuel tank filling
    • Fuel Hosing and Hand Crank Pump - to reach fuel tank in airplanes
    • Tire Glue - for rc cars and trucks to attach tires to rims
    • Carburator Adjustment Screwdriver

    Megatech provides most of these items including fuel and wash in their Deluxe Nitro Support Pack which is custom tailored for RC cars and trucks:

    megatech nitro performance pack

    Hobbico provides all of the necessary items in their Field Pack Deluxe which is custom tailored for RC nitro airplanes and helicopters:

    hobbico field pack deluxe



    Conclusion
    Congratulations...you made it! ...you now know the RC Basics of the RC Hobby!

2 comments:

  1. http://www.youtube.com/watch?v=hxTT_6aByOI&feature=results_main&playnext=1&list=PLE6699E4122650140

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  2. Thanks for sharing all such things. Your blog is very informative and have nice pictures of rc parts and nitro rc car. Nice to see this. Having Rc car is reall fun. I have my own Nitro rc ar and i m loving it and have great expereince with it,
    Regard's,
    Ben Linus,
    Find Out Me

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