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    MAN 33.414 DFA-S 6x6 tipper with drawbar trailer


    Something which I wanted to build for a long time is a tipper truck with a loading crane pulling a drawbar trailer, loaded with some equipment. Which machine that would be didn't matter. The idea already exist in '96 but all these years I didn't found a suitable vehicle which compare to my wishes. After all, I only make models of vehicles which exist in real life.


    In 2000 a local hauler asked me if I could build one of their vehicles. I liked to grant his request. Eventually they thought of their DAF 85CF motor vehicle with loading crane, but I thought of one of their MAN tipper trucks. The MANs are also supplied with a loading crane, with another difficulty I can be fold in behind the driver's cab. And Van Hameren Transport, the company which is all about, also ownes a tri-axle drawbar trailer. So that fits very well behind the MAN, loaded with equipment.


    The LEGO tipper

    Before I started I still had the MAN concrete mixer. I built that one in 2000 and in 2001 I started with the tipper truck. Some components of the mixer I could use for the new model. You can think off the driver's cab, the engine block and a part of the chassis. But while the tipper's chassis is 6x6 driven, and the mixer truck was 8x4 driven, the new chassis had to be totally different. Furthermore the tipper is supplied with a steered back axle and it has hydro pneumatic suspension, in addiction to the mixer which was fully leaf spring suspended.
    The chassis is made to size. The back axles I made with the help of several pictures from press info. Those gave me sufficient information to make a well copy. But while building I changed some parts. A 6x6 is driven on all axles, but you already guessed: how can you manage to make a steered and driven front axle? Indead there are several ways to fix that. I found some concepts by Thomas Avery, but as you can see it is very wide. After all the wheel outcome is rather high because the turning point is too far inside.
    After a while I found another way to build it on a Japanese site. This is better applicable on my model. And I didn't occurred that yet! Anyway, I seems my model has a driven front axle. There's a drive shaft leading to the front axle. Maybe I will try the Japanese idea. The back axle is steered by two small, pneumatic cylinders. This axle is driven.
    As I've said the engine block is taken over. It fitted in the 6x6 chassis as good as in the 8x4. I try to build every truck brand modular. So all components are very well exchangeable. The driver's cab had to be white. Therefore I replaced all blue parts of the mixer cab for white ones. The tipper truck has a steel front bumper. The direction indicators I made of orange tape.
    When I the chassis and driver's cab where ready I started to build the tipping mechanism. It did cost me more time to figure it out than I expected. On the site of Jennifer Clark I studied how she got her skip truck working. Her system is functioning very well, but my model is larger. And a scissors lift needs a lot of power.
    In a meanwhile Herman de Graaf. put an idea into my head. He drew a concept for me in which a lift arm is used. Eventually my mechanism worked out a bit different, but Herman helped me a lot.
    The grab crane was the most difficult part to build. It had to be a fully operational crane and I wanted to make a crane which could be fold in behind the driver's cab. Compared to the original crane the one on the LEGO model is wider. The arm is four studs wide. Next to the movements which makes building such a crane not very easy, you also has lack of space in your model. You have to put a lot of time in it so you must have a lot of patience. The truck chassis was full of stuff already. But the crane also must revolute and a compressor unit had to be placed in the truck chassis. So that are two motors with their drives. The compressor was taken away later. Instead of that I made an external compressor, to the example of one of Jennifer Clark's models. The great advantage is you can create a many more powerful compressor and you have the full controls in one panel.
    The bending in the crane arm took me a lot of time. To get a turn in the arm which is big enough, I glued two pneumatic cylinders together. Yes indeed, but I can use such a part for another model in the future. The cylinders had to fit in the crane arm which is four studs in wide. So you can count how many space there's left: none. With the help of two small technic arm I constructed the turn so it could fold in. The arm can just extend once and it has a rotator, made of a micro motor. Extending a such a crane arm more than one time isn't possible.


    The drawbar trailer

    I wanted to have a drawbar trailer behind the tipper truck. After the truck was finished I didn't had sufficient blue pieces to build it. When I wanted to start building the drawbar trailer I still had the large blue Scania with low loader of hauler Van Elk. I put a huge amount of blue pieces I this model. But I decided to order the parts missing on Bricklink. Actually I didn't need many new parts so this problem was solved very quickly.
    I had a specification sheet of the Nooteboom. trailer so I had all the dimensions I needed. The trailer was built in the late 70s so it's not a very new type. On the goose neck there's a working winch, driven by a geared 9V motor. At the back the trailer has two ramps, the so called 'double folders'. They're working on pneumatics and this time I used the old system. The reasom is that I needed long cylinders, like the one on the forklift from '84 (set 8843). It all works on a hand pump.
    The construction of the drawbar trailer is very simpel: two main beams (one on both sides) takes care of the stability. The axles are rigid and leaf spring suspended. Later I built a liebherr excavator.


    Alterations and extensions

    Through the time I changed some technical parts of the model. The crane wasn't well anchored to the chassis. Next to this I wanted to find a better place for the drive of the tipping mechanism and the compressor had to be removed. I've done these alterations in May 2003 after seeing a wonderful excavator of Jennifer Clark. Because here models aren't very large she made external control panels. It works perfect and you don't have to place many switches in your model.
    The control panel of the MAN consist of four small compressor pumps in line which are driven by two geared 9V motors. In the control panel there are two joysticks: for the three pneumatic functions (movements of the crane arm and the bucket) and one electric switch for the revolution of the crane. Underneath the panel I placed another two electric switches: one for the tipper body and one for the rotator. In this way you can demonstrate a model on an event.
    The compressor function has a pressure limit switch. When the circuit is full of air the 9V motors stops immediately. This prevent keep turning and damaging your motors. It's another idea of Jennifer Clark.


    Other data

    Length 140.0 cm
    Width: 19.2 cm
    Height: 31.5 cm
    Wheelbase: 27.2 cm
    Construction: I have no idea
    Date: May 2000 - October 2002

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    Since 04-11-1999

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