Brandon's Formula Offroad Build: Part 1

Posted: 3/29/11

The latest buzz around Axial has come about after Bender introduced us to Formula Offroad. I was aware of this sport and always enjoyed watching the 1:1 videos, but it never really hit me to build a RC replica of one before. I am a huge fan of Scale RC, so anything I can get my hands on and modify to closely resemble the real thing just adds to the fun factor. The looks of the 1:1 formula offroad vehicles are a bit odd compared to what we normally see offroad in the states, but you can tell that they are built purely with performance in mind.

Take a look at Benders Blog Post for more info on Formula Offroad and his scale version:
Benders Formula Offroad Blog post

After seeing Bender's build progress, I immediately started kicking ideas around for my own. I really liked the look/performance aspect of using the SCX10 as the base and had an old RCP Crawlers Wreckluse chassis that had been collecting dust for a few years... so I thought to myself, PERFECT!

Here is a picture of a stock RCP Wreckluse chassis with AX10 running gear under it. You can see it has more of a "Rock Crawler" look to it with the large stinger on the front.

Now that I had my starting point, I went out and searched for a 1:1 Formula Offroad Jeep to scale down the proportions from. For me, Pirate4x4 is the ultimate source for full-size images and builds.

I was able to quickly find a CJ3 build that I really liked and decided that the overall look would fit my build perfectly. Jeep CJ3 Formula Offroad - Pirate4x4.com.

I wont be following that build exactly since the Wreckluse chassis comes with a modern jeep hood and the cage shape is slightly different, but it can give me a great reference for the overall wheelbase, axle location, and stance.

So here is my Wreckluse chassis stripped down and ready for some "slight" alterations!

From there, I started to take a look at what needed to be changed. First was get rid of the huge stinger. None of the 1:1 Formula Offroad rigs have anything beyond the front axle or body work. Then, I started to sort out the link lengths to get the axles positioned correctly and set the wheelbase. Here is my first mock up to get an idea of what needed to be changed on the cage.

Current parts list for the pics below:
AX10 Axles
Aluminum C's, Knuckles, and straight axle adapters
AX10 Universal Joints
72-103mm Comp Shocks
AX10 Transmission
Axial Rockster 2.2 Beadlocks
Axial AX30714 7x73mm Threaded aluminum pipes
Axial XR10 Linkage Set
Axial 4 link Truss: AX80043 TR Links Parts Tree
Axial Spur Gear Cover: AX80078
Futaba S9157 Servo
Pro-Line Sand Paw Tires
Pro-Line Beadlocks
HPI Sand Thrower Tires
RCP Crawlers Wreckluse

From there it was obvious that even with the stinger removed the remaining tube work in front of the grill/hood also needed to be removed. The old bracing from the bottom of the stinger needed to be modified as well, with the low stance the front links/axle were interfering with the Wreckluse chassis.

So here is the updated chassis, looks a little "stubby" and tall now. Isn't that how its supposed to look though? I'm sure it will grow on me.

Thinking ahead I added this tube in the back of the cage for a rear sway bar.

Now I could have just painted the chassis and called it good, but I felt it was important to leave it raw and finish the build. This way, after driving it for the first time I could easily tear it down and make any modifications to the cage without having to strip any paint off. So I moved forward and started assembling everything.

In the following pics I was able to complete the following:

Body Painted

Suspension/Link geometry sorted out

Battery mount complete

Rear Sway Bar (we will see if the front needs one after the initial drive)

Hood body mounts using SCX10 parts left over from a kit. The body posts were perfect!

Axial orange beadlock rings for the rockster beadlocks

I definitely was able to achieve the look I wanted using the Wreckluse chassis. It took some work and unfortunately it wasn't something I could just bolt together and be finished, but that makes it unique and adds to the overall appeal for me.

Still a lot of work to do!

Install Electronics

Rebuild the Transmission with HD internals

Install Driveshafts

Possibly relocate the front steering links to behind the axle to protect everything

Mount rear tires on 2.2 Rockster Beadlocks with matching Orange rings

Go have fun!!

Stay tuned for Part 2 when I share some of the action shots, hopefully some video, and the final pictures with the painted cage. Of course I will be adding a ton of scale details! Its just too hard to resist!! Thanks for reading.