Granite Granite 4x4 already broke

[Bmansdad]

New to the RC world and got my new granite 4x4 yesterday and the servo (I think) is already broken. It tends to lock left, sometimes straightens up if I adjust transmitter trim, but only for a moment, then it seems to choose to center up to the left or the right again. So I’m stuck going straight or full left/right (depending on where it decides to stick)

Called Arrma and they are going to send me a new servo, but so far pretty disappointed. All we were doing was learning to drive on the back lawn. No hits. No jumps. Just grass figure 8’s

Hoping it was a fluke, just bummed I had the car for 2 hours and now it has to sit for a week.

 

[bikerbob951]

Wow, sorry to hear that. For what it's worth, I've got the Senton 4x4 (same chassis) and I've ran it 5 times now, 3 of those I was really giving it the beans, and I've had no issues. Hopefully the new servo gets you sorted and back to driving. Let us know how it goes!

 

[Jerry-rigged]

Yeah, stock servo's often suck.

Here are a few options I have -

Turnigy 1258TG $35 - I am running this in my Typhon. Great servo, decent price.
https://hobbyking.com/en_us/turnigy-1258tg-digital-titanium-gear-servo-57g-13-5kg-10sec.html

Trackstar TS411MG $16 - I have two of these, only mounted one, in a RC10. Other is planned for a M.Rage that I keep saying I will build as a drifter.
https://hobbyking.com/en_us/trackst...course-steering-servo-11-1kg-0-09sec-57g.html

 

[Bmansdad]

Wow, sorry to hear that. For what it's worth, I've got the Senton 4x4 (same chassis) and I've ran it 5 times now, 3 of those I was really giving it the beans, and I've had no issues. Hopefully the new servo gets you sorted and back to driving. Let us know how it goes!

Thanks, I’ll let you know how it goes. This is my first RC, and I was actually quite pleased with the “giddy-up” this had with the provided battery. With the 2S, It really had some punch (more than I could decently handle) so I’m looking forward to learning to drive this thing with the kid/grandkid.

I figure I’ll be on this forum a few times for pointers.

 

[Bmansdad]

Yeah, stock servo's often suck.

Here are a few options I have -

Turnigy 1258TG $35 - I am running this in my Typhon. Great servo, decent price.
https://hobbyking.com/en_us/turnigy-1258tg-digital-titanium-gear-servo-57g-13-5kg-10sec.html

Trackstar TS411MG $16 - I have two of these, only mounted one, in a RC10. Other is planned for a M.Rage that I keep saying I will build as a drifter.
https://hobbyking.com/en_us/trackst...course-steering-servo-11-1kg-0-09sec-57g.html

Thanks Jerry, good info. As stated, I’m a total Noob to RC’s and, having spent way too much time watching videos before deciding on this one, was surprised to have it break this easily. When my ability to control it gets better, I look forward to doing a little bashing in the dirt part of the backyard, and was hoping to be able to do that, at least for a while, on the original platform.

All that said..... The servo’s you linked to, as with others I’ve seen on the forum, all appear to be the same size. Are these pretty much “drop-in” or are there things to look out for? I’m not looking to hobby and mod things too much (yet).

Thanks again for the info!

 

[Jerry-rigged]

Thanks, I’ll let you know how it goes. This is my first RC, and I was actually quite pleased with the “giddy-up” this had with the provided battery. With the 2S, It really had some punch (more than I could decently handle) so I’m looking forward to learning to drive this thing with the kid/grandkid.

I figure I’ll be on this forum a few times for pointers.

Ask questions, learn the truck, then come back and help all those people that will pick up a MEGA 4x4 for Christmas. Pass on your knowledge.

Plus, we want pics.



And running video. LOL


Jerry

 

[Bmansdad]

LOL... "Running Video" he says. hehehe.

Sure thing, Jerry. How about in a "week to 10 days", when the new servo arrives.

 

[Jerry-rigged]

LOL.. Sorry.

And the servos are pretty much standard. You do kind of need to watch out for mini-size or giant size servos, but both of those I linked are standard size, plug and play. Both can even use the standard Arrma 25t spline servo horn.

When you go to hook up the new servo, first - plug it in, and power everything on. Make sure the steering trim on the radio is centered, This will make sure the servo is centered. Slide the horn on the servo (it may be tight). Power the truck down, THEN install the screw that holds on the horn. Also, be sure to support the horn, don't torque it against the internal hard stop.

Next connect everything, and power it on. check for range of motion. Does the truck steering hit it's hard limit before the servo? if yes, use the D/R on your radio to dial back the servo throw, until it is no longer binding at full lock. This will help prolong servo life.

 

[Bmansdad]

LOL.. Sorry.

And the servos are pretty much standard. You do kind of need to watch out for mini-size or giant size servos, but both of those I linked are standard size, plug and play. Both can even use the standard Arrma 25t spline servo horn.

When you go to hook up the new servo, first - plug it in, and power everything on. Make sure the steering trim on the radio is centered, This will make sure the servo is centered. Slide the horn on the servo (it may be tight). Power the truck down, THEN install the screw that holds on the horn. Also, be sure to support the horn, don't torque it against the internal hard stop.

Next connect everything, and power it on. check for range of motion. Does the truck steering hit it's hard limit before the servo? if yes, use the D/R on your radio to dial back the servo throw, until it is no longer binding at full lock. This will help prolong servo life.

Good info, thanks!

 

[Bmansdad]

Arrma replacement servo arrived today. They replaced the bad ADS-5 (plastic) with the ADS-7M metal servo. This, my friends, is what Customer Service is all about.

Based on this, I’m about 10 seconds from buying the Senton 4x4 for my kid for Christmas.

 

[Bmansdad]

So..... installed the new servo and finally got a couple of packs through it and absolutely love it (I run a short track in my back yard). I went to run it with my kid yesterday, got about 3 minutes in to a pack when it stopped going in to reverse. I ran it 1-2 more minutes and it just stopped. I popped the body off and felt the motor and ESC and they were both HOT. Too hot to leave a finger on either for more than 2 seconds (and I have old mechanics hands). I checked to make sure the battery type jumpers were in the Lipo position (running a 2s) and let it sit overnight. Went to test it today and all the ESC does it flash red. I have steering, but zero throttle. I’ve tried everything I could find on the internet but suspect the motor got to hot for some reason and fried my ESC.
My question.... is it possible I simply got a lemon car or is this new product just junk? Bad servo already. Now no throttle. I’ve ran 6 packs through it since I got it and it’s been out of commission more than it’s worked.
I’ll call Arrma again on Monday, but am so far extremely disappointed in the quality of this vehicle.

 

[Unusual RC]

It is a cheap car to start with.
But that does not mean you could expect yunk electronics.

My experience with the older 2wd brushed Arrma cars was that I fried 3 motors because I used 2S lipo's.

This is a new design and a new type (for Arrma) of brushed motor. What I understand from it they are much more sturdy than the old 15T's

A brushed motor can get hot. But if the esc gets hot there is something wrong.

And indeed the esc could be a faulty one. When you get a new one from Armma make sure it is not your car itself.
Without the motor installed, does the driveline run smoothly without a lot of friction?
A problem here could indeed fry your motor and esc.

And unfortunately a servo with plastic gears in a 1/10 scale car is bound to not last long. That is probably the next in line upgrade after a brushless combo!

 

[Bmansdad]

It is a cheap car to start with.
But that does not mean you could expect yunk electronics.

My experience with the older 2wd brushed Arrma cars was that I fried 3 motors because I used 2S lipo's.

This is a new design and a new type (for Arrma) of brushed motor. What I understand from it they are much more sturdy than the old 15T's

A brushed motor can get hot. But if the esc gets hot there is something wrong.

And indeed the esc could be a faulty one. When you get a new one from Armma make sure it is not your car itself.
Without the motor installed, does the driveline run smoothly without a lot of friction?
A problem here could indeed fry your motor and esc.

And unfortunately a servo with plastic gears in a 1/10 scale car is bound to not last long. That is probably the next in line upgrade after a brushless combo!

Thanks Unusual.... the drive all appears smooth to me, I guess. I really don’t have a value to baseline this against, this being my first RC. As little as it’s been driven, I’m going to assume all is ok. No noticeable binding, grinding, etc... with half a dozen total batteries (3 times on NimH, 3 times on Lipo2s) through it, all on a flat dirt “track” in my backyard, I would think the truck would hold up better. I blow everything out with compressed air between each battery change, I checked every screw/bolt before my first drive, etc....

I get the whole upgrade process, but as a first time RC owner, I’m not lookin to have the biggest, baddest machine in town, I just wanted a car to run around the yard (and occasionally repair shocks/A-arms from tree hits) with my kid/grandkid. For $239, this thing should be driveable after a week or two. Maybe my expectations (based off all the internet reviews, etc..) are wrong. If so, I’m gonna have some ‘splaining to do to my wife.

 

[Unusual RC]

Indeed from a bit of flat surface driving it should not brake so quickly!
Another option could be the motor. The old one had a fan inside for cooling. Driving on dusty dirt also makes it suck up waste, which can get stuck between the magnets and the coils. But most importantly between the brushes and the collector!
Use your airgun to clean out the motor too.

Sounds like your ride is good.
So your motor is my second "suspect".

And about the wife: you choose the wrong hobby! In hobby grade RC cars are the biggest money pit
Bought Arrma for the same reason! But it is fun, so no worries

 

[Bmansdad]

For what it’s worth, the motor still rips, as I learned when I was troubleshooting and turned the controller off and the truck took off across the garage. LOL!

 

[Unusual RC]

LOL
Lesson one: always make sure all driven wheels can turn freely in mid air when trouble shooting
We all find out why sooner or later

Still I would inspect the motor, and blow some air through it!

And when your replacement esc comes, check the heat within intervals!

And keep us informed!

 

[Bmansdad]

LOL
Lesson one: always make sure all driven wheels can turn freely in mid air when trouble shooting
We all find out why sooner or later

Still I would inspect the motor, and blow some air through it!

And when your replacement esc comes, check the heat within intervals!

And keep us informed!

Question, if you don’t mind..... when I ran this thing, before it stopped, I ran through a 5000mah 50c Lipo2s. We were ripping around for the full pack. When we were done, you could not touch the motor or the ESC for more than half a second. They were HOT. The battery was cool as a cucumber.
Is that normal?

 

[Jerry-rigged]

Two thoughts -

popped the body off and felt the motor and ESC and they were both HOT. Too hot to leave a finger on either for more than 2 seconds (and I have old mechanics hands).

Get a IR thermometer. Above 120f-130f, your fingers are no use. Safe motor ESC temp is 160f, danger is around 180f. I use the $12 pocket thermometer from Harbor Freight.

For what it’s worth, the motor still rips, as I learned when I was troubleshooting and turned the controller off and the truck took off across the garage. LOL!

Yeah, been there. Now try it with a pissed off Talion on 6s in a messy garage. Talk about exciting... LOL

 

[bikerbob951]

Well, count me in on the failed stock servo. I've been in contact with Arrma/Hobbico, and they are saying the servo is backordered until middle of January! I believe they are sending me the stock ADS-5 servo instead of the metal-geared ADS-7M that you guys have been sent, despite my direct request for such.

Frustrating to say the least, especially when I've enjoyed the truck so much up to this point.

In the meantime, I've spent another $50 and installed an ADS-15M servo so I can keep driving, on recommendation from my LHS. However, the steering is much slower now than it was originally. I'll start another thread so I don't hijack this one, but I believe I may need a BEC to run this servo.

 

[Jerry-rigged]

Yeah, that ADS15 was designed for the BLX180 crap-tastic ESC. The one good thing about that ESC was the 7.4v BEC, which made the ADS15 a great servo. on 6.0v, it is slow...

Grab one of the Turnigy servo's I linked above, they are cheap, and run great on 6.0v