Sep
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Tiamat 6WD/6WS
This is Tiamat, a six wheel drive, six wheel steering monster mutant truck.
It is based on the Tamiya Clod Buster platform, and originally started out as two trucks.
I built this truck in the fall of 2001, and it has been periodically upgraded ever since.
Lineage
Based on the timeless Tamiya Clod Buster monster truck kit which was incredibly popular when first released in 1988 and is still sold today (albeit as the ‘Super’ Clod Buster)
Powerplant
The truck is powered by three Hacker C50L brushless electric motors. They are more powerful and efficient compared to their more commonly available brushed motor counterparts.
And now some answers to frequently asked questions:
How fast is this thing?
The truck tops out at about 26MPH. While it is not fast for racing truck standards, it’s definitely one heck of a handful for a large, scale-ish monster truck.
How many motors, and how many battery cells each?
The truck has three gearboxes (for each axle), and one 6-cell stick pack of batteries for each.
The motors are Hacker C50L, 10T units.
How many batteries does it need for a run?
On a typical bash day, this truck will consume 40 battery packs, which is about 10 runs or so, depending on how loud i leave the engine speaker volume.
The batteries are carried in a bowling ball bag.
How heavy is it?
The truck closes in at 24.5lbs fully loaded.
Why the name Tiamat?
The thought of a large, destructive, rumbling beast sort of came to mind naturally.
At the time i was thinking of the multiheaded dragon thing from Babylonian mythology.
How long did it take to build?
About four weeks initially, to chassis and rolling stock complete. The whole truck took about another two weeks to get to a running state.
The truck first drove on 20 November 2001.
Six wheel steering? What? Why?
I wanted a maneoverable truck. It has about a four foot turning radius.
The setup chosen worked extremely well. The servo savers are of the Kimbrough black version variety.
The quarter-scale servos (normally reserved for large scale airplanes) that were used are able to turn the truck’s tires standing still while on pavement!
What kind of chassis is it?
It’s a chassis that i made with hand tools, predating my purchasing of proper machine shop tools.
Its made of aluminum and is fairly beefy. Contrary to the beliefs of a barely literate backcountry Floridian hobo, it is not a Sassy brand chassis 
How is the handling?
Actually very predictable, and plush when driving. The truck oversteers because of the torquey servo setup, but tends to drift nicely on dirt. It absorbs bumps reasonably well, with the long travel HPI Savage coil-over-oil dampers doing the dirty work. This vehicle will never have the jump handling of something like a stadium truck but it does have a fairly plush ride over the rough stuff.
How reliable is it with all that weight and power?
This is not my most reliable truck, but it’s rock solid in the right places. The driveline is pretty much bulletproof now. However it has issues mainly with the plastic parts breaking from wear over time, but as i run the vehicle i replace things with similarly designed parts made of more durable materials.
Therefore this truck is like an endless race to convert things that were once plastic to aluminum, what was once aluminum to steel, and so on.
Are any of these chassis for sale?
I don’t have plans to produce these, even in limited production runs. Besides, the total number of 6X6 enthusiasts is fairly small, and the design is fairly straightforward. I would be more than willing to help builders spec one out. Check out the wonderful forums at Scale 4X4 R/C.
Specifications
This section is just for the hardcore R/C crowd. Newcomers, please feel free to skip over, or just let your eyeballs glaze
- ESC – Triple Jeti Master Car Sport, 6 cells. These days, i would go for Schulze or Castle Creations instead.
- Motors – Triple Hacker C50L, 10 turn.
- Servos – Triple quarter scale- two Futaba 9301s for middle and rear. Single Hitec servo up front.
- Wheelbases
- Front to mid axle – 15.5″
- Mid to rear axle – 8″
- Radio – Futaba T9CAP surface, with analog servos.
- Lights – Tamiya Tractor Trailer (generation 1) kit.
- Sounds – Tamiya Tractor Sound (generation 1) kit.
- Suspension – 4-link, dampened with HPI Savage oil units, 40 weight oil.
- Steering – Claw type, 6WS. Front axle moves opposing the rear and middle axles.
- Balance – Almost 50/50, CoG about right above the tires.
Pictures
This photo gallery contains a bunch of pictures from when the truck was initially built, to its current state.
In addition i have made a few higher resolution pictures available.
They are Portable Network Graphic (PNG) files that most web browsers should be able to read.
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Higher Quality Image 01 (1280 x 1024) 2,310KB |
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Higher Quality Image 02 (1280 x 1024) 2,321KB |
Movies
These are some movies with Tiamat in action. More clips will be added over time.
Please note that since i am a cheap bastard, you will want to save these links to your machine before playing. Thanks!
Tiamat_bashing02.wmv (6.4MB) – Bashing around again in our favorite Central Park proving grounds. This was the first time i really felt comfortable with all that brushless power on the truck. Filmed in Summer of 2003.
nyc_cp_bashing01_small.wmv (11.1MB) – Tiamat and a bunch of other trucks and vehicles bashing around in the proving grounds.
I guess if you like watching radio controlled stuff it is fun, but the fact that what was being filmed was just bashing around, it might be boring to those outside the hobby.