Big Rock Kaladeth’s Big Rock 3S

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kaladeth

kaladeth

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Arrma RC's
  1. BigRock 4x4
  2. Limitless
Hi all. Will update as I go!

List of mods:

11/27/2023
- HobbyPark aluminum steering blocks and rear hubs

1/17/2024
- Pro-Line Badlands MX28 BELTED wheels with 17 mm adapters
- Promodeler DS635BLHV Servo

1/24/2024
- Hot Racing Aluminum Differential Yoke
- Arrma Outcast 4S Input Gears (metal)
- Arrma Outcast 4S Differentials (metal)

1/25/2024
- (removed) Hot Racing ATF257EX Steel 57T Duel HD Slipper

3/1/2024
- Pro-Line Performance Shocks

3/14/2024
- Arrma Kraton 4S V1 center brace bar
- M2C chassis brace
- M2C 17mm Hex Adapters

3/21/2024
- Castle MMX8S ESC
- Castle 1717 1650kV Motor
- (removed) SaGa 21t Mod 0.8 pinion gear
- Custom ESC mount

3/25/2024
- M2C Motor Mount and Chassis Brace

4/10/2024
- SaGa 25t Mod 0.8 pinion gear
- SaGa 57t Mod 0.8 spur gear
- Aluminum Slipper Eliminator
- Hot Racing ATF125HL01 Aluminum Reinforced Slider Driveshaft LWB Chassis
- SMC HCL-HP 4S Battery x2
- PMT Q1 Super Soft Tires (rear)
- PMT Q3 Soft Tires (front)

Someday Maybe
- Mojave 4S arms, driveshafts, hubs, turnbuckles, and 17mm hexes
- Custom magnetic body mounts
- Custom lights
- Team Associated steel turnbuckle balls
 
Last edited:
IMG_0325.jpeg


Lights power check. Looks good.
 
IMG_0341.jpeg


Headlights done. Yay! 😀 Cutting holes in the polycarbonate body was a challenge. I used a mix of knife, dremel, clippers, and a bunch of swearing 😂 . Any tips for me before I cut the 4 other holes?

I also had to get the little light controller board so I can use the remote to switch the lights on and off. Will be using splitters too.

I am also slowly realizing these lights won’t survive a proper bashing session (I am sure you all were aware of that already haha)… so will most likely buy a second body soon for the fun outings. Anybody selling a spare/old one, hit me up!

More to come.
 
Replaced the stock Spektrum servo with a ProModeler DS635DLHV servo and 17F-15T servo arm.

Start.

IMG_0703.jpeg


Unscrew ESC and switch.

IMG_0704.jpeg
IMG_0705.jpeg


Remove 4 screws on the bottom to remove the receiver box. Remove the 1 screw to release the servo link.

IMG_0706.jpeg


Take the truck away and focus on the receiver box.

IMG_0707.jpeg


Remove 4 screws to remove the stock servo. Save the servo link and the screw that secures the servo saver to the stock servo.

IMG_0708.jpeg


The ProModeler arm is 2mm taller than the stock servo saver…

IMG_0709.jpeg
IMG_0710.jpeg


So, used a set of 4 Reefs RC servo washers as spacers to offset / lift the servo. This provides enough clearance between the bottom part of the arm and the bottom of the chassis.

IMG_0711.jpeg

IMG_0712.jpeg


The ProModeler servo arm is also 2mm wider for the stock servo link, so I used 4 0.45 mm thick M3 washers.

IMG_0713.jpeg


Reassemble.

IMG_0714.jpeg
IMG_0715.jpeg


Done!
 
Last edited:
kaladeth said:
Replaced the stock Spektrum servo with a ProModeler DS635DLHV servo and 17F-15T servo arm.

Start.

View attachment 351086

Unscrew ESC and switch.

View attachment 351087View attachment 351088

Remove 4 screws on the bottom to remove the receiver box. Remove the 1 screw to release the servo link.

View attachment 351089

Take the truck away and focus on the receiver box.

View attachment 351090

Remove 4 screws to remove the stock servo. Save the servo link and the screw that secures the servo saver to the stock servo.

View attachment 351091

The ProModeler arm is 2mm taller than the stock servo saver…

View attachment 351092View attachment 351093

So, used a set of 4 Reefs RC servo washers as spacers to offset / lift the servo. This provides enough clearance between the bottom part of the arm and the bottom of the chassis.

View attachment 351098
View attachment 351094

The ProModeler servo arm is also 2mm wider for the stock servo link, so I used 4 0.45 mm thick M3 washers.

View attachment 351095

Reassemble.

View attachment 351096View attachment 351097

Done!
Click to expand...
Well done sir👍. Now go rip up some dirt will ya 😁
 
Ran two packs through and all the time was thinking… I’m going to need more speed… 🤭 . Any suggestions on an ESC-Motor combo? I know an XLX2 and 2028 won’t fit - already checked 😂.

In the meantime the shock oil arrived so I was finally able to install the Pro-Line shocks! I had to use the included longer shock ends to clear the lower A arms.

IMG_0733.jpeg

IMG_0732.jpeg
 
Last edited:
Sweet Ride bro! I was thinking about running lights on mine too. Might have to hit you up to get a better idea of how you set that up.

Currently running HW max10 w/ hobby star 3674 on 3s/4s. Runs a little warm, was thinking about running max 8 and a 4074.

FYI, MMX8s and a 1717 1650kv will fit if you cut out the reciever box if you decide on going w/ castle. 😎
 
@J.Rambo thank you! Yes please do - happy to help. Lights are a must have for night bashing. I am thinking of 3d printing some light buckets and using hot glue as a lens.

And yes that’s my prime combo candidate. Trying to see what’s needed to accommodate the longer shaft.

SPMXSM2000 - Spektrum FIRMA 3200KV
Shaft Length: 18.5mm / 0.73"

CASTLE 1717 SENSORED MOTOR - 1650KV
Shaft Length: 20mm
 
Last edited:
kaladeth said:
@J.Rambo thank you! Yes please do - happy to help. Lights are a must have for night bashing. I am thinking of 3d printing some light buckets and using hot glue as a lens.

And yes that’s my prime combo candidate. Trying to see what’s needed to accommodate the longer shaft.

SPMXSM2000 - Spektrum FIRMA 3200KV
Shaft Length: 18.5mm / 0.73"

CASTLE 1717 SENSORED MOTOR - 1650KV
Shaft Length: 20mm
Click to expand...
I've got that castle setup in my vendetta (same size as big rock 3s). I don't recall having any issues as far as shaft Length. Just had to chop off the reciever box to get the mmx8s to fit right there.
 
kaladeth said:
Replaced the stock Spektrum servo with a ProModeler DS635DLHV servo and 17F-15T servo arm.

Start.

View attachment 351086

Unscrew ESC and switch.

View attachment 351087View attachment 351088

Remove 4 screws on the bottom to remove the receiver box. Remove the 1 screw to release the servo link.

View attachment 351089

Take the truck away and focus on the receiver box.

View attachment 351090

Remove 4 screws to remove the stock servo. Save the servo link and the screw that secures the servo saver to the stock servo.

View attachment 351091

The ProModeler arm is 2mm taller than the stock servo saver…

View attachment 351092View attachment 351093

So, used a set of 4 Reefs RC servo washers as spacers to offset / lift the servo. This provides enough clearance between the bottom part of the arm and the bottom of the chassis.

View attachment 351098
View attachment 351094

The ProModeler servo arm is also 2mm wider for the stock servo link, so I used 4 0.45 mm thick M3 washers.

View attachment 351095

Reassemble.

View attachment 351096View attachment 351097

Done!
Click to expand...
I somehow missed this thread, nice build! That servo is one of the best out there. It does pull some serious amps, though. I’ve never been able to run a 635 on a stock ESC’s BEC without brownouts. HobbyWing or Castle ESC’s handle them fine when plugged directly into the receiver.
 

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