By:
Brandon Wilcox, Thomaston CT
July 9, 2007
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pictures to open high resolution image in new window.
My goal was to build the ultimate rc rock
crawler, and that's exactly what I did. In part 1 of
the article, you saw all the goodies: Thunder Tech Racing
CVD's, Thunder Tech Racing Aggressor Steering Kit, RC4WD
Aluminum Steering Knuckles, Hitec 5998 Titanium Gear
Servos, and The Crawler Store Stick Chassis. This was
all controlled by a cheap and simple Traxxas 2 channel
radio. There was one speed control powering both brushed
motors. Not anymore. It was time to upgrade to the best
in the industry, dual Castle Creations Mamba Max ESC's,
dual brushless motors, and a Spektrum DX6 radio system
controlling it all.
The first item I got installed on the
truck was (2) Castle Creations Mamba Max ESC's. They
are high power ESC'S that can handle any turn motor,
have drag braking, and can be programmed by the Castle
Link USB cable that connects to your computer. You can
adjust the throttle curve, brake and drag brake settings,
motor power, and many other important features. For
motors, I went with the new BM14 1000KV brushless motor
from The Crawler Store. They are smaller then a brushed
lathe motor, lighter, have more power, and have better
braking control. What more could I ask for! For pinions,
I went with RCguy.com 8 tooth pinions. I find in my
trucks that their pinions hold up really well, and give
my trucks incredible torque.
By using 2 speed controls, and the right
radio, you can set up your truck to have independent
front and rear steering, and to have dig, so when your
approaching an extremely steep climb, the rear axle
shuts off and prevents you from flipping backwards.
You can also use dig to go around corners at an extremely
small turning radius. The Spektrum DX6 is one of the
few radios that has enough channels and features to
do this for us. The DX6 has channel mixing, a very important
feature that allows the 2 speed controls to get the
same signal from separate channels, and allow one of
them to shut off with the switch of a button. As you
can see in the photo below, sometimes you want to move
just the front or rear tires, without moving the other
axle. Independent steering will allow us to accomplish
this, as well as the ability to crab walk, or to steer
both axles in the same direction so your whole truck
goes to the left or right, while keeping the same approach
angle.
One of the things I loved about the Mamba
Max is that I can plug it into my computer and adjust
a number of settings. You spend time dialing in your
entire truck, so you mine as well fine tune your speed
controls. Its really easy, install the Castle Link software,
plug in the cable to the USB port on your computer,
then plug in the other end of the cable to the speed
control.
Once the software opens, you will have
multiple tabs with different options to fine tune your
speed control. I immediately cranked up the drag braking
to 70%, and made some fine tuning adjustments to the
throttle curve, and the brake curve. At the end of my
messing around, I ended up with the following settings:
Another thing to remember is to make sure
both speed controls are programmed the exact same way.
Because the Clod Buster is using 2 axles, any difference
in speed between them will create clod stall, or could
stress the slower of the 2 motors that was set up differently.
Everyone's driving style is different, so play around
until you find a setting that suits you.
So how did the new and improved Ultimate
RC Rock Crawler perform? It rocked. I got thru some
serious obstacles that I never could have gotten thru
using a Y harness for true 4 wheel steering. The drag
braking is awesome, I can climb a vertical boulder then
go to neutral and it wont rock or move, it will just
sit there until I control it. Its also great going down
hill, you can slowly go downhill, then stop, and not
worry about rolling down, or get a reverse penalty in
competitions for trying to hit reverse for braking.
The truck is definitely 100% better then it was before,
the only problem for me was getting used to the DX6's
stick radio setup. It took me about 1 hour of driving
before I felt remotely comfortable with it, and even
longer to feel natural with it. The BM14 brushless motors
from The Crawler Store were awesome. They had tons of
torque, and they looked awesome. The Mamba Max ESC's
are amazing, they can be used in any RC application
with ease. Not only do they support any motor (brushed
or brushless), but you can set them up for your racing
rig, a crawler, a basher, whatever you throw at it.
Definetly one of the best ESC's on the market today.
The Ultimate RC Rock Crawler is definitely more capable
then it was before. I still would like to narrow my
Giant Tracs to give me a narrower stance, but everything
else on the truck was dialed. Have fun crawling!
