Two years after I posted my third tiny RC, the Mercedes Citaro (video), I made my fourth one! Itís the replica of one of the most specific trucks. Iím sure you have already realised it on the small picture, before you opened its mocpage! The type of it is Renault Magnum. The idea of building this truck at this scale and with this brand method is quite old, but other projects and university stole the time. So Iím very happy, that itís ready! Hope you like it, too! :)
The length of the whole vehicle is 45 studs. The width of the tractor is 6,4 studs (16 plates), the width of the trailer is 6,6 studs (16,5 plates) without mirrors and other design elements. The scale is minifig scale. It has the two compulsory functions of a tiny RC, propulsion and steering. It contains approximately 820 pieces.
Because of two developments, the motions of the truck are absolutely lifelike. It'ís possible to solve almost all extreme situations, which happen with trucks in real life!
Of course a video :) :
You may realised that the trailer is not exactly horizontal. If both axles are fixed, the front wheels donít touch the ground. The weight of the trailer is on the front axle, the other axle and the wheels on it are only decorations.
It was a real challenge to figure out the front! I used almost every direction. I'm very proud of the result :)
We are transporting something very dangerous!
You may remember my yellow Daf Truck, the grille of it is my body icon everywhere (video). The Renault is similar to that, everything is in the semi-trailer, but it has two very important differences (the two developments).
The motor drove the wheels of the trailer at the Daf. It meant that the truck couldnít move, the trailer couldnít push the tractor if the angle of the trailer and the tractor was too close to 90 degrees.
In this truck the rear wheels of the tractor are the driven wheels. You can see the method on the pictures, how I brought the spinning from the trailer to the tractor. The right angle is not a problem any more!
I used two cardan joints in this truck and in the older one, too. The difference is the aim of the joints.
Two joints rotate the axles into vertical position in the Daf. One of them compensated the angle, which exists in bends. It means that the motor canít rotate the axle, if the angle of the trailer and the tractor is smaller than 135 degrees. The cardan joint canít spin above this angle.
In the Renault two joints have the task of compensation. So right angle is not a problem any more!
By the way we still have the good old problem with the steering. I tried to use servo motor, but it was a fail. The motion goes through a wormscrew, many gears and the two cardan joints from the motor to the steered wheels, so the backlash is big. The servo motor canít bring back the wheels into middle position after steering. Servo motor is useful, if it is as close to the steered wheels as possible. For example in a bus. In a Mercedes CitaroÖ If you are technic fans, you may remember that we can find cardan joints between the wheels and motor in 9398. But that set is very big, so the same difference is smaller problem there, as at minifig scale.
The inside picture without lines and letters:
I used the same building method here, as in my monorail. There is a technic frame inside, and it is covered by system elements. The frame is stable and works well without the elements of the body.
Wow! Thanks for these long and amazing comments my friends! I really appriciate them and I'm very happy that you like it! :)
I like it
January 3, 2015
I am always very intrigued by these tiny RC models. In many ways, they are more impressive feats of engineering than the large Technic models with loads of functionality. Putting it all together in a nice-looking package must be extremely difficult. Great work!
I am absolutely stunned and amazed by the beautiful engineering of this model. To pack so many big Technic components into such a small space and to get the working functions is so impressive. Some really ingenious design solutions to the problems too. Great work: like a well designed wrist watch.
Absolutely fantastic work, Gabor. I really liked watching this in action on the video. Very tricky to engineer at this scale, the way you've crammed in the functions and not sacrificed any looks is pure genius