Bender’s Formula Offroad Build: Part 2

I have been driving the heck out of this rig for the past month or so, with little issues. But, there were a couple things I wanted to change/add. One was our OD ring and pinions for a little more wheel speed. I also replaced the stock 3 link with our 4 link parts tree for added durability and a more scale look. Last few mods, I bent my drag link at a slight angle so I could remove the spacer from the knuckle. That spacer adds a lot of stress to the knuckle, by basically acting like a pry bar every time the rig takes a hard hit on the front wheels. With the drag link bent it removes that stress, and will be more reliable over time. Then, I installed a short M3 set screw to the unused holes in the knuckles. These will help stop the knuckles from bending/breaking while tumbling down the hills at speed.

A few shots of the most recent mods:

Front axle and 4 link truss
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Rear axle and 4 link truss
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Bent drag link
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A few action shots:
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See Part 1 of the build HERE.

Bender’s Formula Offroad Build: Part 1

Formula Offroad (aka FOFF) is a sport that has always intrigued me. These guys have to be some of the craziest/bravest drivers in all of motor sports. They build these custom “Jeeps” sporting upwards of 1000hp and nitrous to climb the steep walls of sandpits. Adorned with monster paddle tires these rigs can drive up steep sandy faces that most people wouldn’t even think possible. Similar to rock crawling there are gates laid out on the hill side that drivers must negotiate in order to finish, points are given for each set of gates they successfully clear. They also do a time trial type course too, where the fastest time is the determining factor. One thing that I as an R/C enthusiast has always been attracted too is hill climbs. After watching a few of the newest 1:1 FOFF videos, it sparked a fire under me. So, I decided it was time to build an R/C version of these 1:1 monsters. My intent with this project was to build a realistic looking version of the real thing and see how capable I can make it.

For those that have never seen a 1:1 FOFF event.

Specs for this build:
Axial SCX10 kit
Futaba 4PK radio
Futaba S9157 steering servo
Traxxas VXL brushless system
MaxAmps 5250mah 3S lipo
Pro-line Sand Paws – front
Panther paddles – rear
2.2 Axial 8 hole beadlock wheels
Narrowed HPI Rubicon body

Photos:
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Body off shots:
In order to mount the battery directly over the front axle, and lower the overall ride height of the chassis, I had to do 2 things. One, mount the steering servo outside the frame rails. Steering is a little limited with this set-up, but at high speeds less steering is easier to control. And two, flip the tranny around so the motor endbell is facing the rear of the truck, which gives me more room for my battery.
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BTA steering:
This set-up took a while to dial in, in order for everything to clear as the suspension cycles. But, it is working great so far. One thing to keep in mind when mounting your servo like this, double check to make sure your tires aren’t going to hit the servo while steering.
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Narrowed body:
In order to get the look right on this build, I had to narrow a body. The 1:1 FOFF rigs have the full paddle tire outside the body panels. I could have added wheel wideners to get that same look without narrowing the body. But, the wideners will add a lot of stress to your axle housings if you take a big fall. So, I cut just over an inch out of the center of this body, and re-attached the 2 halves with back to back servo posts, spare Lexan, and a little Shoo Goo.
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Video of this SCX10:

Recognizing the potential this aspect of R/C has, RCCrawler.com recently added a Formula Offroad section on their forum.
http://www.rccrawler.com/forum/forumdisplay.php?f=210

Existing Axial parts list:
1 – SCX10 Kit (AX90014)
2 – 2.2 Wheels (AX8097)
1 – Spur gear cover (AX80078)
1 – AX10 Wheel hex (AX30429)
1 – Aluminum knuckles (AX30496)
2 – Driveshafts (AX80011)
1 – 35mm grey posts (AXA1424)
1 – 91mm grey posts (AX30524)
1 – 15mm grey posts (AXA1420)

Axial parts yet to be added:
2 – 4 Link parts tree (AX80043)
1 – Steel transmission outputs (AX30544)
2 – HD ring and pinion gears (AX30395)

If you like driving R/C’s at high speed off road, then you will love driving one of these FOFF builds. High speeds on flat ground is one thing, high speeds on a steep sandy hillside is another. So fun!!

See Part 2 of the build HERE.