Getting started guide
Every hobby and sport has a learning curve for newcomers. Whether you’re getting into tiddlywinks, comic book collecting, BMX, or (of course) RC, there is equipment to master and lingo to learn. I assume you know RC stands for radio control, but from here on, I’ll indulge in only one other assumption: that you are a newcomer (I won’t call you a “newbie”) looking to learn about and become part of this great hobby. Are you fired up to join the fun? Here’s what you ned to know.
SELECTING A VEHICLE
Part of what makes the RC car hobby great is the diversity of vehicle types to choose from. These are the basic “flavors”; match your sense of RC excitement to the terrain types listed to see which style is right for you. We also include “hot picks” that reflect popular choices-but not all the choices!
Buggies represent the classic look of off-road RC, and they’re a blast to drive. Very rough terrain bounces buggies around despite their long-travel independent suspension systems, but trails and smooth dirt are no problem. Most buggy kits are 2WD but 4WD kits are also available.
HOT PICKS: Kyosho Outrage, Tamiya Baja Champ, Associated RC1083 Sport, Team Losi Double-X Sport.
These are generally modified 4WD tourers that can handle mild off-road conditions, such as baseball diamonds and dirt roads. They have a bit more ground clearance and suspension travel, and most use some type of inner shell to protect the drive train.
HOT PICKS: HPI RS4 Rally, Yokomo MR-4 Rally, Schumacher SST Rally, OFNA Z-10 Rally.
Closely related to buggies, racing or “stadium” trucks have fully independent suspension and the same type of chassis layout. However, for greater stability, they have more suspension travel and a wider stance than buggies. Stadium trucks use smaller tires than “monster” trucks for better handling. They’re typically 2WO, but HPI has a 4WD model-the RS4 MT.
HOT PICKS: Associated RC1OT3 Sport, Team Losi XX-T Sport, MRC MT-10S, Tamiya Stadium Blitzer, Kyosho Outrage ST.
The “classic” 4WD monsters are Tamiya’s Clod Buster and Kyosho’s USA-1, but less expensive 2WD big-tire trucks deliver much of the same look and performance. They’re not very fast, but for anything-goes off-road abuse, monster trucks can take it all.
HOT PICKS: Tamiya Wild Dagger, MRC Ironman, Kyosho Tracker, Traxxas Stampede.
Thanks to the simple direct-drive, rear-axle setups and rudimentary suspension systems used by pan cars (so named for their flat, “pan” chassis), this type of vehicle delivers lots of “go” for a lit, tle “dough,” but be warned: they arent very durable and should be run on smooth pavement only. Body choices for pan cars include touring-car styles, NASCAR racers and lowslung IMSA types.
HOT PICKS: Bolink Sport 2000, Associated RC10L3 Touring, Trinity Street Spec.
This red-hot segment of the hobby is still growing. The realistic cars offer easyhandling 4WD, can be equipped for very high speeds, and they’re generally durable. Touring cars, however, are bound to the pavement and not meant for off-road use.
HOT PICKS: HPI RS4 Sport, Traxxas 4-Tec, Tamiya TA03, Tamiya TL01, Schumacher SST Sport, Yokomo MR-4TC.
Just about every vehicle type listed here can be had as an electric model or nitro-powered, and nitro trucks and touring cars represent the largest share of the “gas” market. Many gas models aimed squarely at the firsttime RC hobbyist include partial assembly, electric starters and even prepainted bodies, in some cases. While these kits are easily the simplest nitro vehicles to operate, we still feel rank beginners should start with an electric car. The convenience and simplicity of battery power make it easier to master the basic elements of RC, not the least of which is driving. Electric motors are also more forgiving than nitro engines. Even the most abused motor will generally still run, whereas nitro engines can only tolerate a small deviance from the optimum carburetor settings and correct piston/sleeve fit. If you just have to make that first car a gas car, be sure your local shop is nitro savvy, or enlist the help of someone with nitro-power experience. Here are some kits to consider:
Traxxas Nitro Stampede, Rustler and Sport; DuraTrax Maximum ST; Kyosho Nitro Sandmaster and Tracker MRC Thunder King (all are available as kits, assembled kits, or “ready-to-run” with installed radios–check out the October issue for a shootout of these trucks!).
NITRO TOURING CAM
HPI Nitro RS4 RTR; Traxxas Nitro 4-Tec: (available as a kit or RTR); Tamiya TG10; Kyosho GP Spider Mark II; OFNA Nitro ZIO Sprint, Schumacher Nitro SST.
1 1/8-SCALE BUGGIES
Although this category is emphatically “not for beginners,” some kits are much easier to complete and operate than others; the Kyosho Inferno DX and MP-6 Sport, Thunder Tiger I Mirage and OFNA’s prebuilt buggies are the best picks. The soon-to-be-released DuraTrax Axis-the hobby’s first RTR 1/8 buggy-will probably also be a list-topper and could revoke the segment’s “no beginners allowed” status; look for a review soon.
WHAT ABOUT “RTR”?
Ready-to-run (RTR) cars are nothing new, but the latest RTR machines are more complete than ever before. For example, MRC’s Hammerhead (shown below) is available with a painted body, installed radio, battery, and charger (as are some other MRC kits). Traxxas also offers prebuilt, prepainted kits, and DuraTrax’s “Maximum” series of nitro vehicles are ready-to-go right out of the box. RTRs are certainly convenient, but you do pay a premium for the factory assembly, and you miss out on the invaluable experience and know-how you gain by building the kit yourself.
Should you buy an RTR? If you like assembling models, and mechanical things in general, you’ll love building an RC car. See if you match this “snapshot” of the ideal RTR customer:
You are not confident of your building skills, or..
Building an RC car doesn’t interest you.
You lack the space or time to build a kit (space shouldn’t be a problem; a kitchen table is fine. Expect to spend three or four evenings completimg your first kit).
You have the time and the space but you want to start driving NOW!
Battery chargers are separated into two broad categories: mechanical “timed” chargers and peak-detecting chargers.
Mechanical chargers use a clockwork timer that is set to charge for 15 minutes-sometimes 20. When the time is up, the charger switches off or goes into a trickle-charge mode that charges the battery very slowly. Very few packs actually reach a full charge in 15 minutes, so another crank of the timer knob is usually required to complete the charge process; the battery pack must be monitored closely to assure a complete charge [when the pack is warm to the touch, its fully charged). Mechanical chargers aren’t very convenient, but they are inexpensive and reliable.
Peak-detecting chargers actually sense when the battery is fully charged then shut off. This is convenient and ensures that you get the most from your battery. This type of technology used to be expensive, but the latest simplified peak chargers on the market are downright cheap, and I mean that in a good way. MRC’s Super Brain and Hobbico’s Piranha are two good examples, and they’re only a few bucks more than a timed charger. Go for a peak charger right from the start; you’ll be glad you did.
All kits include a few essential tools that are not part of the typical household tool kit, and with the help of some common kitchen-drawer tools, such as a pair of pliers and a screwdriver, they will get your first kit built just fine. But to get the most from the hobby, it’s best to pick up some highquality implements; as funds allow, add better tools to your toolbox. Stock your box with the following, and there will be few tasks you can’t handle.
No. 1 and no. 2 Phillips screwdrivers
Kit-supplied ban wrench
High-quality Allen wrenches (sized to replace the kit-supplied “L” wrenches)
Curved body-trimming scissors
Most entry-level RC cars accept the common, 6-cell stick-type battery. If you’ve priced battery packs, you’ve no doubt noticed that some packs are much more expensive than others. The difference in price reflects greater capacity, and really pricey packs use a matching system to group cells for best performance. I know you’re wondering what all that means, so here’s the scoop:
Just about all sport packs have a big number on them: 1400, 1500, 1700, 2000, or 3000. That number refers to the cells’ capacity in milliamp hours (mAh)-a measure of the amperage the pack delivers for one hour under a constant load. For example, a 2000mAh pack can handle 2000 milliamps (or 2 amps) for one hour. Simply put, the greater the capacity of the pack, the longer your car will run.
“Matching” is a process that tests individual cells for capacity, voltage and internal resistance. The cells with matching numbers are grouped together-hence the term “matched pack.” The benefits of matched packs include longer run times, increased voltage and more consistent power delivery as compared to an “unmatched” pack of the same type of cells. Does it matter? Not for playing around and most off-road stock racing, but for other types of organized racing, matched packs are a must.
All electric RC cars require some type of a throttle, or speed control, to allow the car to operate at variable speeds. Speed controls can be divided into two basic types: mechanical and electronic.
Mechanical speed controls use a servo to move an arm over a set of electrical contacts to select one of three forward speeds, or reverse. This type of speed control, usually called a “3 step” control, does not allow the driver to make subtle throttle adjustments, but this is rarely a liability. Another type of mechanical speed control uses a wire coil resistor and wiper arm (much like a slot-car controller) to allow smoother throttle control, but today’s kits rarely feature these (Team Associated and Team Losi “sport” kits are the notable exceptions). All mechanical speed controls vary motor speed by placing resistors in the motor-battery circuit. To limit speed, the resistor burns off some of the battery’s energy as heat. As you might guess, it isn’t terribly efficient to limit motor speed by wasting unneeded battery power as heat, and additional energy must be diverted to power the servo that operates the mechanical control. In addition, mechanical speed controls tend to require frequent maintenance-all compelling reasons to equip your car with an electronic speed control-better known as the ESC.
Electronic speed controls are self-contained, solidstate throttle units that vary speed by switching the motor on and off at a super-high rate, or frequency. If you were to flip a switch on and off once per second, the switching frequency would be 1 hertz [ 1 Hz). Many inexpensive ESCs switch at
1000Hz or higher; that makes for super-smooth throttle control and much greater efficiency. ESCs are available with reverse, as well as forward-only models typically aimed at racers (reverse is not allowed in sanctioned races). These days, even the most inexpensive ESCs are durable and reliable, so don’t worry if your budget requires you to get the cheapest unit in the shop.
Motors may all look alike, but they’re quite different inside. Here are some things to keep in mind.
STOCK VERSUS MODIFIED. Stock motors take their name from stock-class racing, the class for which they were developed. In stock class, everyone must use a stock motor to keep things fair. All stock motors use bushings to support the armature (the part of the motor that actually spins; the end of the armature is the shaft that sticks out of the motor) and have nonadjustable endbells (the part of the motor the wires connect to). Although generally less expensive than their hand-wound, modified cousins, stock motors are neither as adjustable as mods, nor as fast@ but they aren’t “slow” either.
Rebuildable stock motors, introduced by Trinity through its Paradox line, offer many of the same maintenance benefits previously only available to mod motors; they can be completely disassembled and rebuilt. Despite this level of accessibility, most have been extensively temper-proofed to maintain parity in stock-motor performance. If you race stock class, these are the motors to have.
For play, machine-wound modifieds are often best; they are inexpensive, durable and rebuildable and, depending on which “wind” you purchase, they can also be blazing fast. Modified motors use ball bearings to support the armature and may feature an adjustable endbell. By twisting the endbell, the motor’s brushes (which transfer battery energy to the armature) are repositioned in relation to its magnets. This relationship is the motor’s timing, and changing the timing can alter rpm and torque.
HOW MANY WINDS?
Modified motors are described by the number of winds and turns. Winds are the number of wire strands that are wrapped around the armature, and turns are the number of times the wire (or wires) is wrapped around the armature. Hence, a 14 double (or 14×2] has two strands of wire wrapped around the armature 14 times, and a 19 quint (or 19×5] has five strands of wire wrapped around the armature 19 times. Wire thickness also changes with different winds; generally, the fewer the strands, the thicker the wire.
What does it all mean? Generally, fewer turns make for more power, but at the expense of efficiency (your batteries won’t last as long). Fewer strands give more torque or low-rpm power, while more strands give greater power at higher rpm. For the best balance of speed, power and run time with off-road vehicles and tour, ing cars, try a modified in the 16- to I 9-turn range. Trinity’s Speed Gems, the Team Orion Pilot line and the Reedy Qualifier series all offer suitable winds.
HAND-WOUND OR MACHINE-WOUND? There are two ways those winds and turns of wire get wrapped around the armature; a machine or a human does it-by hand. Machine-wound motors are more cost effective: the winding robots don’t take home a salary. or break for lunch, and can wind whole bunches of armatures in minutes. People, on the other hand, require such niceties as paychecks, and they take much longer to wind an arm. The finihsed product, however, is the best it can be. Each wind is as tight and as neat as possible and uses the least amount of wire; extra care is taken when soldering the wire to the armature and when balancing the final product. Hand-wound mods are faster and more efficient than machine-wound mods of the same specifications, but they are more expensive.
Racers opt for hand-wound motors whenever they can, but don’t think yours must be hand-wound to race; the less expensive machine-wound motors are competitive for all but the most intense contests, and you can probably buy two for the price of one good hand-wound one. For play, machine-wound motors are definitely the way to go: they’re cheap, rebuildable and powerful. And that’s more fun!
The addresses of the companies mentioned are listed alphabetically in the Index of Manufacturers on page 241.
Copyright Air Age Publishing Dec 1999
Provided by ProQuest Information and Learning Company. All rights Reserved