MOC Mercedes Dump Truck

[roppie11]

[MOC] [WIP] Mercedes-Benz dump truck.

Hello,

I decided to go make a moc. I bought the arocs last november and i was like:"hmm, i have enough stuff to build a good moc."

so i started to make a plan. A simple painting in word 2013 and i made some challenges and requirements for myself. Here is a list:

RC functions:

Driving

Steering

Outtrigger

Sideway Tipping(which side is not decided yet.)

Manual functions:

Openable doors

Switch rc/handdrive

HoG steering

Other specs:

Suspended, driven tracks

Suspended steering frontwheels

Outrigger will have 2 stages, driven by one motor with the use of a differential.

There will only be one outrigger on one side, depends on what side the truck is gonna dump.

19 studs wide (made the tracks and they turned out te be 19 studs wide)

PF stuff

1x XL motor for driving

2x L- motor for outtriggers and tipping

1x M- motor for steering

Will probably use the cabin of the arocs (42043)

2 receivers

batterybox

Challenges:

Driven tracks(first time i work with tracks)

2 staged outriggers will be difficult.

Unusual way to dump.

Find a way to switch from handdrive/steer to RC.

Advanced gearbox to make all this possible

here is a rough sketch i made in word.

i know this is gonna be a weird non-existing truck. but my goal is to make a really advanced truck and to learn things from it. i'm sure i'll do.

1. i only play with lego on sundays so don't expect to see updates midweek.

2. i also have no idea how it's gonna go and i don't know if I'm able to do all this. this is my first moc and this not a technical easy one.

3. another thing i wanna tell you is that i don't have receivers now. I had 2 from 8043 but the are both broken.

4. i ordered 2 by the customerservice broken bricks, but they were not available so i don't know when the moc will be finished. i also made no deadline for myself.

the tracks

now about the tracks, it was pretty difficult for me to build proper tracks, since i have never build one.

the first problem i ran into was the good length. i built a track, all pretty well, but when i put on the actual trackpieces, it turned out that they were a half track too long. it just didn't fit. i also could not remove a piece because otherwise it would be too short. i experimented a bit with it but i wasn't able to get it right. Then i got the idea to look in the building instructions. so i did and i had a nice fitting track. i have to say, it is still a little bit loose, but that's probably supossed to. but then another problem came along. on a 5*7 bracket i put a small turntable to have a sort of suspension. but when i made my fitting track and put it on, the thing was waay to wide.

(note: the photo's are taken with my smartphone. I don't have a normal camera so quality is pretty bad. sorry for that.)

that's the reason i had to make a whole gear system in the tracks. you can see them on the picture above. the gears are coming out of the turntable right in the middle of the track. it took quite a while to lead the axle to the actual wheel. but that's done and i am satisfied wih the result. the black line shows how the axles and gears are going

here are some more pictures.

on the picture above you see how you can detach a track. it's pretty simple. i put 4 of these pieces(I don't know how to describe them) on the turntable with 3l pins. i now have 4 cross hole to attach to another piece. i just put 2 4l axles with stop in it as you can see. the axles go through 5*7 bracket and i put a half yellow bush on the underside.

as written earlier the total width is 19 studs. the tracks are 5studs and i have 2 of them. i have a 5*7 bracket. with two beams and the 2 small turntables which are 1 stud. the tracks are each 37 pieces long which brings it in total to 74 pieces.

I was happy to find out that it was as wide as the arocs because i'm going to use the cabin. Here is a picture.

this is the result.

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the outrigger

I just finished the outtrigger. I wanted an outrigger with 2 stages like 42009 which could be expanded with one motor. i used a differential for that

this is the first stage. you see that i used 2 bevel gears to drive 2 gearracks to expand outwards. then i used a u-bracket

to transfer it down. the outtrigger is laying upside down, so the axle is going down, not up.

this is the whole thing(not finished)

you see that i used a small LA to do the downward movement. this means it can go down 4 studs.

the LA is sticking out but i don't care about that since 42043 has that as well and that's a official lego set.

here is the finished one:

as you can see, it can expand 7 studs sideways and 4 studs downwards. if it is retracted, the thing is 22 studs wide which is a little bit wider than the tracks.

it is 8 studs hight and 9 studs wide. 22*8*9. i used 26 gears in total. it took me a day to build and i'm pretty ok with it.

below is a picture from the outrigger as seen from the bottom. you see the differential.you turn the differential with the big black bevel gear, the right side goes to the

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front wheels

today i moved on the front suspension. i disassembled the 42043 B-model and i only left the cabin+grille.

when nothing was left but the pieces, i began building. i had a great idea(i thought) my idea was this:

i attached those black pieces and a ball joint. then i use some liftarms and attached it to a frame. it worked pretty well and i was happy, yeah this is going so well!!

look under here, full independent, it can steer, no problem. yeah!!!

then i saw something horrible, it was a 'little bit' too wide. i experimented a bit but i found out, that those wheelhubs combined with liftarms are too wide. look at the second picture:

luckily, i remebered a topic about suspended axles, so i looked throug my history and fount this topic.

i looked for a while and build this axle: (finally good quality ) i used the road wheels, not the balloon ones.

the building instructions on LDD are 'great'. #not. but i managed to build it.

i ran into a few problems.

1. i don't have a powerjoint. so i had to use a normal 5x7 bracket for the differential. a

2. another problem. if i don't use the powerjoint, how am i gonna attach the axle to the chassis.

i used a sort of life axle idea. or is it a real life axle?

3. to drive the differential,i had to use a half thick 20z bevel gear. i first did that but it was not sturdy enough. the gear slipped out several times. after messing with it for a while, i came up with the idea to just turn the axle around and use a double bevel gear.

4. the steering didn't work at first because, it could not move forward to the axle, if you know what i mean. if you steer a wheel, the gear racks moves a bit forward, but the bracket was in it's way so that didn't work. i put the gear rack on the upside and it had space to move, but the gears slipped. i placed just two blue 5x3 L-beams to fix that.

all in all, i changed quite a bit of the axle and only 50% of so is from the original building instructions. check it out below.

it can steer very well and has a bit ackerman geometry. it works fine though. i attached the spring to the liftarm so i don't have to make a whole structure to attach it to the truck. it has a travel of 2 studs. that is not much but it works, and i'm fine. it was not my goal to have as much travel as possible.

i'm pretty satisfied with it, it works fine. the next step is attaching the arocs grille and cabin. i think, i'm gonna use the 6l fake motor as well. the axle is 19 studs wide, just like the tracks and the cabin

summary:

i am building a non existing truck with driven and suspende. tracks and steered, driven, suspended frontwheels. it will have a sideway dumping and an outtrigger to that side with two stages like 42009. it will be rc and have a switch so you can drive manually. i'm gonna use the arocs cabin because it's a wonderful piece of lego. this is my fist moc so i don't know how it will turn out. for details and building process, check out the whole first post.

if have now build:

- tracks

- front wheels

- cabin and grille

- outrigger

i have to build:

- nice frame to put on the cabin and grille.

- gearbox for all functions and motors and a switch : manual-->rc.

- a mechanism to dump sideways.

- a bed, you know, where you put in the stuff to dump.

Edited February 8, 2016 by roppie11

[Sariel]

Unusual way to dump? I know a girl or two who could inspire you here...

Edited January 31, 2016 by Sariel

[Hartley25]

Sounds like a challenge good look also you can find the receivers on eBay if that helps

[roppie11]

Sounds like a challenge good look also you can find the receivers on eBay if that helps

tnx for info, but at the customer service, you can get one for free, if yours is broken. but you have te send your broken one back.

Unusual way to dump? I know a girl or two who could inspire you here...

+1

but i don't want to place just a LA but do something unusual. I don't have reasons but you know, always good to play around a bit.

[roppie11]

i made some progress, everything is written in the first post.