Unimog U900
My third, unsuccessful Trial Truck. Features 4×4 drive, full indepent suspension and R6 piston engine.
Datasheet:
Completion date: 31/03/2009
Power: electric (Power Functions)
Dimensions: length 46 studs / width 25 studs / height 31 studs
Weight: 1.95 kg
Suspension: full independent
Motors: 1 x PF Medium, 1 x PF XL
An unfortunate result of my attempt to enter 2009 Truck Trial season with a brand new vehicle. It was intended to be small, lightweight and as simple as possible. Therefore I’ve decided to model the shortest version of the legendary Unimog truck being produced at the time.
The truck was built in a traditional way, with layers of bricks and plates reinforced by vertical liftarms. There were no differentials at all and the suspension utilized the 8880 set’s suspension components, replacing the universal joints with knob wheels as the universal joints get damaged in the Truck Trial quite often. The number of motors and electric components was limited to a single battery box and a single IR receiver controlling drive & steering. For the sake of stability both battery box and the drive motor were located low under the chassis, with the battery box moved close to the rear axle in order to compensate for the cabin’s weight. I have initially intended to build the cabin with liftarms and panels, but I didn’t really like the look of it and eventually chose to build a ‘fullbrick’ cab. I have, however, failed to maintain the proportions and the resulting cabin was too tall and placed a bit too high.
The decision about the cabin has dramatically increased truck’s weight – from approx. 1 kg with bare chassis and 1.4 kg with cargo platform to the final 1.95 kg. It had a great impact on the stability and performance of the model. Eventually it turned out that the truck was having serious problems with everything but driving straight ahead. A meticulous analysis revealed that it was because of the bracings keeping the knobs inside the suspension’s rocking levers. While they performed quite well before, now they tended to bend under the truck’s full weight. As a consequence the knob wheels became slightly displaced, and came into contact with other parts of the suspension. It has crippled the truck so severely that I decided to abandon this chassis design entirely, seeing no space for improvements. My first idea was to rebuild the truck from a scratch, but after a careful consideration I have canceled the Unimog project and started to build a 4×4 truck with longer chassis and two differentials. So after all, this model has never been driven outdoors.
@will
Because it didn’t work.
why didn’t you make a video?
This thing looks beast!
yea i kno but i like the chassis and ive made mocs tht suck but i like to work it out thts why i asked
@David
I guess you missed the small fact that it didn’t work well.
i like it post instructions bro;-)
@will
94 mm tires on 8880 wheels.
what wheels and tires are those because it looks like balloon tires on 8880’s wheels
@fraser
And all it takes is to download instruction from here: http://sariel.pl/downloads/
how the hell can you get 4WD and steering? i have been working on it for months
@will
Yes, I did not.
so did you not compete for most of the 2009 truck trial season
i own the 8880 set and the new 4×4 off roader set and never relised that the whells where the same size untill now and am inspired to built something with them thank you sooooooooooooooooooooooooooooo much
@matthew
At least $1500, I think.
How much would one of these trucks be worth?
@Sariel Thank you, maybe i will post it on Youtube some day 🙂
@MoseMor
I simply make sure that gears are braced in something firm & tight. If they have no place to slip, if they are kept together by something, they won’t slip. You have to place them inside some strong structure.
I`m building a pretty large truck right now, but because of the weight the gears slips, and the truck gets weak. How do you make your trucks so heavy, without making the gears slip? Nice unimog 🙂
ahhhhh! that is exactly what i tried to build about 12 years ago! mine is way less detailed: no suspension, balloon tires with d-cell battery caps as hub caps, a differential for no reason (no motor), manual steering, i just recently put rear steering on it but it is terrible. !!!!
@arnau
The same. It slightly touched the tire.
I’m building a 4×4 and I’m using the same wheels an tires as you, but when I put the steering link it touches with the tire. how did you put the steering link on your Unimog?
@Sariel
ow ok
@legobuilder
I’ve seen it, I don’t think it’s really fit for Truck Trial. It has a low ground clearance and an apparently short travel of suspension. Anyway, I already have a prototypical chassis for the Alvis.
Maybe I know a very nice truck trail model the BARC it’s a heavy tank transport amphibios vehicle big enough for trucktrail
@Arnau
Easily if there are 3 studs of space between them.
I don’t understand how you can fit knob wheels between the two liftarms.
@Brydol
Ta belka nie łączy kół. Pod nią jest 16-studowe cięgno które łączy zwrotnice, ale nie jest ono przymocowane do podwozia, tylko wchodzi pod tę belkę w taki sposób, żeby nie przesuwało się na boki. Poza tym jest luźne, więc tylne zawieszenie może pracować.
Jeżeli połączyłeś tylne koła sztywną belką, to jak w takim przypadku działają wahacze ?
I love it
Awsome it is very realistic in particular the motor between the seats.
@djtermoz
Yes, they are 94.8 x 44 R tires. The piston engine had moving pistons made of 3-studs long axles with stop.
Forget the performance, proportions, etc…
Love it! Looks decent, definitely like an Unimog. What kind of tires did you use with 8880 wheels? Are those maybe the 94.8 x 44 R balloon tires from the 8297 set? I had no idea there are other (truck) tires that would fit those rims.
Was that a working engine or just a dummy?
@legobuilder
No, I took it apart promptly after taking photos.
can you make a video?
@Murcielago53
Thanks. I am using a backdrop (a 2x10m paper reel) plus special lamps for photography. White backdrop is excellent for the black models, because of how it reflects in their parts. I just wish I’ll be able to get a decent camera sometime soon.
at least it looks awesome. Can’t wait for your next 4×4.
One question about your pictures, are you using a backdrop, or editing software to make them look so clean and professional.