From Brushed to Bonkers: Arrma Fury Goes Brushless

Introduction

 My son was on a campout with a group of guys, and so it is not always that much fun to head over to the track by myself. I have a project sitting under my table, and it is time to get going on it.  It is time to make the Fury truly furious.  

So, I figure with my son gone for a weekend, this might be the perfect time to upgrade to brushless.  I wanted to surprise him with it, but when I got it all working, the Fury was pulling wheelies.  It was hilarious and awesome!  I couldn’t keep it to myself.  So, how did I get here?  

The back story

Last winter we had a speed controller try to heat the house and burn up the truck in the process.  We ripped out the battery, and the smoke stopped.  I wrote Horizon, and they stepped up.  I think I had a replacement in about a week.  Nicely done.  I put the brushed speed control into the truck, and all was well again. 

Then about a month later, the UPS truck showed up at my door.  I was not expecting a package, and the package was from Horizon Hobby.  I opened the package, and it was a brushless speed control.  What?  I did not order this!  I thought maybe I had something in my cart and someone in my house made an order.  I looked at the invoice, and nothing was charged to me.  Did I arrive in the blogosphere already, and people are sending me stuff?  That would be so cool!

I got on their chat to inquire.  I put on my detective hat and monocle.  Okay, I didn’t, but that would have been totally awesome.  I reached someone on their chat.  They said, “Whoops!  We never marked that we sent you an ESC.  It’s going to cost more to send it back to us, so Merry Christmas!”  That was pretty epic.  Basically, they forgot to note that they fulfilled the warranty, and accidentally sent me a brushless speed control (ESC) receiver (RX).  

I waited for a sale and bought a Spektrum 4000KV 550 motor.  I figured it is not the biggest and most powerful motor, but it is waterproof.  It should give the truck a boost.  It will work with this ESC, so let’s see what happens. 

Meanwhile, back at the brushed garage

 I made an honest effort to hold off installing it because I wanted to test the brushes system.  I came to realize that it is just a hassle to deal with brushed motors.  Then you toss in the problem of the snow and dust, and you realize that your stress relief has become a stroke risk.  I would get to a spot, plug in a battery, and the motor would go…. pause… go….pause…. I was like…. Crud!  Now I need to pull the whole motor apart.  I need to really service this motor and armature.  I was cutting corners by only doing the brush replacement.  I raised my white flag and realized that you might be able to get a brushed motor to hit 40mph, but the stress just is not worth it.  

(I had to return the chassis back to the clean slate. The nice thing about the Arrma Speed Control is no tape! No need to clean the chassis because screws mount it.)

I still have the blue Fury with the original brushed motor.  That one does about 21 mph on the best day.  I wonder how fast a brushless one will go? 

Getting it all to work

I had a problem: no directions.  I figured, who needs directions?  I got duct tape.  I can fix it.  I have done ESCs on plenty of cars throughout the ages, so how hard can this be?  I know that with Arrma you push the bind button when you power on the ESC/RX unit.  When the light starts to blink, turn on the transmitter.  It takes about 30 seconds, and you are good to go. 

Well, I got it all mounted.  I tried a radio that I had lying around from an eBay score.  Well, this is the first time that I put batteries in it.  The radio would turn on, beep three times, and then shut down.  I tried putting the radio in calibration mode.  This is when you turn the wheel left and hold the brake position on the lever.  When you have the wheel turned left and the controller in full brake position, you push the on button.  It really helps to be plastic man at this point, but if you don’t have the luxury, it can be done.  

I got the controller to turn on.  It was in calibration mode, beeped three times, and then shut off.  Clearly, I was not holding something right…. so I tried two more times.  You know what they say about insanity, right?  Well, I lived it 3 times before I realized the problem was with the radio/transmitter.  Thankfully, I had another one bound to the blue Arrma Fury.  Yes, I have a problem. Hi, my name is Paul, and I have a fury problem?  That will probably send me to anger management, so best to keep that to myself. 

I grab the transmitter from the blue truck.  I put the brushless ESC/RX in bind mode.  Turn on the radio, and boom!  It pairs as it should. The problem: the brushless motor responds to the trigger, but I have no steering.  Dang! Now what?  I keep messing with it, and the same thing happens over and over again.  Remember that insanity part?  Yup, still allowing history to repeat itself.  

I finally have an idea: “Ya know….maybe the servo goes in the plug, and the cooling fan goes on the three pins.”  Well, I switched the wires, and what do you know?  All of a sudden the car comes to life.  I have steering and throttle!  Amazing what happens when you pause for a minute to contemplate a problem. 

(I made the mistake of plugging the fan into this plug. That is major no bueno. This plug is for the servo. So, if you turn on the speed control and steering is not working…. it’s because you did not plug the servo in here. The three pins are for the cooling fan.)

(The ESC/RX is on backorder. I cannot find it on Amazon, but it is listed in Amain's catalogue.)

I slapped on a pinion gear, set the mesh, and took the truck outside.  Arrma does not promote this idea, but I removed the mesh plate.  I just set the motor old school.  I put the motor in the groove and made sure the gears were mated.  Bravo!  We got power, and I continue to void warranties baby! 

(The motor plugs straight across to the ESC/RX. It is literally straight forward.)

Initial Run

I took the truck outside to see how the truck ran.  I am running a small pinion gear (19t) to give the truck some umph out of a corner.  I am pretty sure that on a 3S with a little bigger pinion gear, this thing could hit 60mph. It is fast!  Initially, I was doing wheelies and trying to keep the truck from flipping backwards when I gave it the beans.  I just learned to ease on the juice rather than do the full juice.  Once the truck starts going forward, I would just gradually apply more power.  However, wheelies are always cool.  When I put it in the dirt, the thing just shot some pretty impressive rooster tails.  It was hilariously fun!

(I thought that I could just swap the pinion gear, but it turns out that you need a 5mm one. I bought a bag on Amazon.)

I know that I spouted off about doing a brushed motor to do 40MPH when I initially scored this Fury off eBay (Story here).  I will grant that a lower-turning brushed motor will add speed if you upgrade, but you better be ready to replace brushes and rebuild the motor often.  I tried to do the speed runs on the brushed motor.  The problem was that it was like I spent more time going to the hobby store to get parts than driving the truck.  This was getting old.  So, I am saying that brushed motors might be great for bashing, but it falls into the penny-wise and pound-foolish category.  

This truck is seriously doing wheelies!  Did you read that?  Full-on wheelies!  It made me laugh out loud it was so awesome.  Now, I have to either turn up the gearing to give it a bit more top end or just put a wheelie bar on it.  Yes, this thing is a handful in the dirt.  That’s why we start with this in the RC world.  I would not want to be inside the crashed truck.  I am going to have to keep playing with this truck, and we will be doing some GPS testing.  

Conclusion

There is a night when the parents go and have dinner at the campout.  I saw my son and could not keep the secret.  Yup, I’m still a kid in an adult’s body.  I told him that the Fury does wheelies now!  We left and picked him up at the rendezvous point.  He took a nap and was examining the Fury before I could even show him.  We did not have time to run it the night he got back, but the next time we got out to the track, he just died laughing.  The truck is insane!  So, the next plan is to get a GoPro stuck on the back of the blue one to follow the red one around.  The world needs to see the joy this truck brings.