Elphinstone Easyloader Road Train trailer in scale 1:17,5. It features PF, lights and solid axle suspension.
About this creation
First time I laid eyes on the YT movie on the real trailer was somewhere around July 2009. Some one posted this video on a Dutch LEGO forum and basically challenged the Dutch truck builders to create a model of it. In the months that came I spend some time thinking and figuring out how to solve some issues, but did not start building it yet. Finally after about a year, July 2010 in this week of from work I started actually building and developing this model. I started out in mixed colors and it is for the mixed colored version that I managed to develop it as it is right now. The blue and white colors are only esthetic but off course very important. From the very beginning of this new project I realy was looking forward to give it its current color scheme.
At the start of thinking about building a model of this quite complex trailer I knew simplicity would be the key. Studying movie on the real trailer for inspiration, but immediately let go of it and find my own unique ways in translating it in to building with LEGO.
What I basically did was writing down all of its functions and figure out which I could combine. From the very beginning I started to reduce the use of motors and stuff like that because of the limited space. With this in mind two major decisions where made:
1) the model will not have its own power supply and
2) only one PF IR Receiver will be used and so only two functions with there own motor
Both decision basically had to do with the limited space in this model since it has an open structure. This single receiver is build in the first trailer close to the king-pin. The trailer has to be connected to the truck since it has no power supply of its own. From here both functions are distributed to both first and second trailer using PF extension wires as well as the older type of wires.
For more pictures on this model click this to check out my Brickshelf Gallery.
When sliding up the second trailer unto the first one the fourth U shaped log holder pushes the others to the front of the trailer. I have absolutely no idea how this works on the real thing, but I managed to get the same functionality and that is what it is about.
This wasn't that hard to figure out, but how on earth do I get them back in place? It took me quite a while but in the end I managed. For this mechanism I used elastic string, with this the holders are pulled back in place. What drives it is an endless chain using Technic Chain Links
About the spacing of the log supports on the first trailer. I locked the supports with the correct spacing using axles and axle joiners. Before attaching the cord I stretched it as far as it could (this was an exiting moment, will it brake or not). Lucky for me the cord has this point it does no longer stretch. I am afraid I'll have to replace the cord once in a while.
There is one drawback with the use of a cord. While unloading the trailer I have to keep in mind there is a cord that I don't want to be damaged...
I realy enjoyed building and developing this system. There where quite some bumps to take, but hey I don't mind, what else to do with my spare time...
As far as I can tell the real trailer has a divided braking system. The second trailer holds its breaks while the truck backs-up with the first trailer and dolly. With this the dolly is moved backwards to reduce the second trailers length. This is not how I solved this problem, let me explain what I did.
Inspired by the first trailers chain to move the U holders I came up with the idea of moving the dolly using a similar chain.
With this chain the dolly can be moved back and forth as needed. This moving is powered using a single M motor. With a worm gear powered at the same time with the same M motor the U holders are lowered and raised. Because of the worm that is needed to reduce the speed tension is created to keep the U holders up and steady.
This project started out as a trailer solo project. So far all of my previous projects were truck/trailer combinations. Because this trailer is special and quite expensive as well I decided to go for a solo project. As time passes I started changing my mind. Since this trailer is mainly used in Australia I thought it come with a day cab truck with typical Australian looks to it.
As with all my trailer, and trucks as well, they are compatible with each other. With this concept I am able to haul it with ever truck I like.
On this truck there is this other topic here on MOCpages for you to check out.
After I finished this trailer I did tell my self to install lights. I didn't want to at first maybe because it was challenging enough already with out it. Since all my models have lights installed I convinced my self to do so anyway. A total of 6 PF light units are installed and I have to admit is was realy realy hard to do so. Especially the wires and the black 2 x 2 connector blocks where quite hard to hide. Most difficult part was the dolly. Since this part also transfers all wiring to the second trailer it already was quite stuffed.
In the end I can conclude that is was far from easy but real fun building this complex trailer. I think I managed to give it the functions it needs and with that very nice looks. The truck I didn't want to build at first is a very nice project too.
Quoting Bricksonwheels MOC
I think this thing is underrated here. If you look at the moc's that get loads of credit this is hundred times better.... the problem is, it is no robot, and it does not carry guns...
Wow...thanks buddy...!!! I can install guns, maybe that helps... :-)
This is crazy! I can't believe that is made out of technic. It seems far to impossible! Fantastic work there my friend, that mechanism is really smooth and well timed. The quality of your MOCs are outstanding. Keep up the excellent work!