Granite Voltage -- FIRMA

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jlorenzen

Just send it
Messages
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Location
NW Ohio
Arrma RC's
  1. Kraton 8S
  2. Kraton 6s
  3. Notorious
  4. Raider
  5. Talion
  6. Typhon 3s
  7. Voltage
I picked up one of these little 1/10 rigs on Prime Day... $30 off and small enough to run in the house and give the dog some exercise.

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For being a "cheapie," I like the motor being closer to mid-motor rather than being rear-motor, which is what deterred me from a comparable ECX vehicle.

My LHS had a $99.99 Firma combo that I had no idea if it would work, but I loved the price and figured why not? It is an 85A ESC with a 4000kv motor.

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I had an extra ADS-7M lying around from the Typhon, so I opted for that rather than using one of my red 25kg Amazon ones.

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The spur gear is molded to the "input shaft," if you will, and has a bearing on the end, just pressed it. I was surprised to see some degree of adjustment available on the motor mount, fittings for 16t (stock), 19t, and 25t. I am going to purchase the two larger sizes for more speed, of course, and to reorient the motor leads, they are in a position I am not too comfortable with (see below).

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The ESC was my favorite part about this whole thing... the mounting holes were in the exact same spot and it thrilled me. I was prepared to fashion a bracket out of aluminum but no need!

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Running this off of a 11.4V, 5200mah, 50C Lectron battery, it is a phenomenal fit. Arrma has spoiled me with the convenience of body clips that mount to the body, so I added these bad boys. the holes were in there from the factory, so I can't take credit for the symmetry ? Paired this to my Noble NB4 with the FGr4S receiver.

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Next steps will be:
- Larger pinions
- Receiver box
- New servo (burned the 7kg up after about 20 minutes of driving)
- some extra goodies

This can definitely fill a void when the big boys are out of commission.
 
Very cool cheap build,think I'll try my own voltage build. I think I seen somewhere on this voltage portion of this forum that somebody had switched the gears to either .08 or mod 1.A 2WD ARRMA WOULD BE TOTALLY DIFFERENT FROM REST I OWN. I bet you that thing will haul azz on 3s with 4000kv?!?!?
 
Very cool cheap build,think I'll try my own voltage build. I think I seen somewhere on this voltage portion of this forum that somebody had switched the gears to either .08 or mod 1.A 2WD ARRMA WOULD BE TOTALLY DIFFERENT FROM REST I OWN. I bet you that thing will haul azz on 3s with 4000kv?!?!?
She moves around pretty good, no doubt! I have no complaints up to this point. 3S is plenty for what I plan on using her for.
 
So happy with it, it's a proper basher now!! I'm almost thinking it can get 50+ on the 25t pinion... Standing backflips from this right now. Goes up trees nicely

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The Integy spur cam in, and WOW... this is a surprisingly well made piece. Very "weighty" if you will, fit is perfect.

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Disassembled the entire rig after I lost power to the left side, just to open up the diff and see it is in visually perfect condition. Swapped in a new one while I take a dive into the original one.

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New body came in as well, the original was in... less than fair condition


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Reassembly will take place tonight, I had to go get more grease for the gears. The body is going to be treated will Flex Seal spray. Tbone racing bumper on the front as well... while I wait for them to stock the wheelie bar (desperately needed for this rig).

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So the Integy spur slots in nicely, but I think the gear teeth are slightly oversized. The mesh seems to be way too tight and it gets friggin warm while applying throttle. We'll see how it holds up over time. Also, this rig is HEAVY in the rear... I will have to weigh this thing and compare it to the stock one... absolutely bonkers.

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Going to go up in pinion tooth count eventually, but I will have to clearance the chassis to allow the motor leads to clear it (have to be rotated upwards). I also installed the Hot Racing 6S output cups. I pushed them into the housing there because they fit perfectly. These will clearance themselves to give them a bit more wiggle room, I'm sure. If not pushed in all of the way, the set screw doesn't sit entirely on the shaft. I'll take some shaved plastic over losing a driveshaft/cup.

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I was also ecstatic over the fact that this receiver box was a direct bolt-on (had no idea, thought I was going to have to 3M it on). Such a clean install, I was over the moon once I realized it.

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I fastened the on/off button down to the chassis as well. Again, there are two holes punched out that line up PERFECTLY for this switch to be screwed into.

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Next is reassembling the rig with OEM arms (RPM backups coming) and a TBR bumper. Still waiting for the wheelie bar to come back into stock :rolleyes: also swapping out the Phillips-head screws for sockets wherever possible.
 
This is amazing! I was thinking of picking up a Fazon for this exact reason! They are stupid light, and would make great ramp fliers.

Have you thought about using some valve lapping cream to help "break in" the gears? Not great if power is being lost to heat from too tight of gear meshes.
 
This is amazing! I was thinking of picking up a Fazon for this exact reason! They are stupid light, and would make great ramp fliers.

Have you thought about using some valve lapping cream to help "break in" the gears? Not great if power is being lost to heat from too tight of gear meshes.
Come to think of it, I do have some of that lying around... good idea, I might have to do that!

Thanks for the idea!
 
Nice build, just picked one up on BF, wish I never seen this thread lol, going to be hard to not slap a brushless system in!
 
Nice build, just picked one up on BF, wish I never seen this thread lol, going to be hard to not slap a brushless system in!
It is an awesome little basher for sure! It's honestly one of my favorites to just pick up and go!

Sorry for the delay in updating the thread, was spending some quality time with the family over the long weekend. I am not sure if I was unlucky or if it is a consistent issue, but the Integy spur seems a little oversized in terms of the gear teeth. The spline side meshes beautifully with the idler. Once the pinion is in, it dang near locks up.

I am going to work at the teeth a little bit and see if valve lapping cream helps the mesh. Breaking in the teeth should help, as it seems as though the spur digs into the pinion's body.

I also learned that you can't install the HR output cups all of the way into the chassis, they rub on the ID and kills a lot of power. They need to be backed out about 1mm and locked down.

I will post my results once I massage the spur and convince it that it wants to be a part of the Voltage! ? Also, if T-Bone Racing is here, MAKE THE DAMN WHEELIE BAR, PRETTY PLEASE.
 
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It is an awesome little basher for sure! It's honestly one of my favorites to just pick up and go!

Sorry for the delay in updating the thread, was spending some quality time with the family over the long weekend. I am not sure if I was unlucky or if it is a consistent issue, but the Integy spur seems a little oversized in terms of the gear teeth. The spline side meshes beautifully with the idler. Once the pinion is in, it dang near locks up.

I am going to work at the teeth a little bit and see if valve lapping cream helps the mesh. Breaking in the teeth should help, as it seems as though the spur digs into the pinion's body.

I also learned that you can't install the HR output cups all of the way into the chassis, they rub on the ID and kills a lot of power. They need to be backed out about 1mm and locked down.

I will post my results once I massage the spur and convince it that it wants to be a part of the Voltage! ? Also, if T-Bone Racing is here, MAKE THE DAMN WHEELIE BAR, PRETTY PLEASE.

I put my HP cuts all the way against the body eventually they got looser. But I hear you.
 
I put my HP cuts all the way against the body eventually they got looser. But I hear you.
Yeah, that was my plan initially, but my power loss was rather substantial. I planned on putting an o-ring and shim in the opening to help seal it.
 
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