42043 Mercedes-Benz Arocs 3245

[Saberwing40k]

Anybody has any idea why trucks like this need 4 steering front wheels instead of 2?

Interesting question, see below or my answer.

It is due to the heavy loading capability of the truck. As you drive a fully loaded cargo bed and want to steer, you'd need a steering type that needs to take up the forces, both tangential and centrifugal. With only one steering axle the truck might lose grip on the surface and the steering would not enable smooth turning of the vehicle, as the load is not evenly distruted and push the cargo loads forwards into the steering axle. By having a second axle, the load is distributed more evenly and enable smoother steering.

When wehicle is turning, each wheel follow it's personal trajectory. Non steered wheels too. So, for any number of axles only one axle can be fixed to make perfect turn. The point of keepenig 2 axles fixed in trucks like this - sacrificing this perfect turning geometry a bit for more simple and more robust construction that can handle heavy load.

Actually, you are both wrong. The Arocs, and most European trucks have two steered axles due to laws about axle load. For instance, over here in the US of A, it is very uncommon to see a truck of any kind with more than 3 axles. Unless, of course, you are in Michigan, where you see trucks like this:

This configuration is due to Michigan have archaic (and asinine) laws about bridges and per axle load limits. Because of the per axle load limit being so low, even a normal standard trailer , which has 2 axles anywhere else in the US, sometimes has 8 or more in Michigan. Then there are the frost laws, and other stuff, but it's pure legalese, and not a very good read, so I can't really summarize.

But, that's just for tractors. I have seen a couple of trucks in the States with two steering axles. All of the trucks I have seen with that configuration have a crane on them. That is because if the crane is mounted in the middle of the truck, and is quite heavy, and would cause a single front axle to exceed the weight limits.

Example:

However, the additional steering axle adds complexity, so many of the trucks I have seen have the crane at the rear, which removes the need for the added axle, and allows the crane to easily reach over a trailer, as they are often paired with, for delivering precast concrete sewers and rock slabs.

So, TL;DR version, having two steering axles is to improve weight distribution, and keep axle weights in check.

[lcvisser]

Unless, of course, you are in Michigan,

I was amazed to see these every morning when I lived in the Detroit metro area:

And, consequently, a lot of blown tires by the side of the road.

[Brickthus]

For European trucks, the tax and weight bands favour particular configurations.

This means a lot of trucks have gone for a single powered axle at the rear, with double powered axles only for trucks that go onto building sites (tippers, cement mixers). The Arocs is one of those.

More common for delivery trucks is a tag (lifting) axle behind the rear powered axle or a centre-lift axle just in front of it. Chinese-6 (2 steering axles and a rear powered axle) used to be common in previous decades and is becoming more popular again.

For a 4-axle truck, Chinese-6 with an extra tag axle at the rear is becoming more common. I saw a tanker like that today.

Where a truck has a fork lift slotted into the rear bumper, or a rear crane, the rearmost axle may be steering instead of lifting.

For multi-wheel trailers on an artic with more than 3 axles it is more common in Europe to see steerable trailer wheels. The usual alternative is 2 or 3 fixed axles in the middle of a trailer. Sometimes those trailers have tag axles; I have seen both tag and centre-lift on a 3-axle trailer. We don't have provision for road trains in the same way as the US or Australia, though the UK has examined the idea. One cartoon showed a passing place in the middle of the road train!

Mark

[Mestari]

Here is a photo of what I had leftover.

It seems LEGO stopped giving us 12 tooth bevel gears as spare. When did it happen for the first time? Was that gear strengthened in any way?

[DillBrick]

anyone recommend this set?

[allanp]

Yes, me

[MaxSupercars]

anyone recommend this set?

We all recomend it! (See posts in this thread)

The set contains all wanted features!!! sprung axles, new steering system, PF and Pneumatic functions, big good looking set for I think good price... :)

Max...

Edited August 18, 2015 by MaxSupercars

[syclone]

For all Arocs Dump Truck owners!

Please don't drive like this!

Max...

Nah, the traffic signs just were too low and he decided to change that going the stupid way...XD

Edited August 18, 2015 by LXF

[thomol]

Some thoughts.

I got my copy August 1st, and after letting it ripen on a shelf for a couple of days I built it during five building sessions and a total of 8.5 hours. It was a fun build, especially the front and rear axle assemblies, and the resulting model looks good on the shelf (with one exception, see below). All functions work fine, I haven't experienced any problems with the pneumatics, they work fine even if there is a tight fit with 8 tubes going through the turntable. And contrary to what I thought beforehand there is no need to fit a PF switch to operate the motor; the redesigned switch on the battery box is super easy to operate compared to it's predecessors. Oh, and I like the weight of the whole thing, heavy models are more impressive than lighter ones, regardless their functions and aesthetics. All in all its a must have, no doubt about it!

What's not so good then? In my eyes the crane is totally out of proportion compared to the rest of the truck. I see people complain on the placement of the wheel arches on the second axle and the wheel size, asking for the old 68.something tires to return, but those issues are nothing compared to the crane proportions. First of all the crane is to tall even in its lowest position. In real life it would rip down every traffic sign portal it would pass, even with the bed lowered... Secondly its much to bulky, not counting the tubing it has a width of about 30% of the width of the truck. If it was a heavy lifting crane like the one on 8258 I could understand its size, but the Arocs has a clamshell and really doesn't need a big crane. What I would like on a model of this size is a crane arm with a maximum width of 3 studs, inluding tubing, using only 1xN pneumatic cylinders. I understand that such a solution would make the model less playable, with decreased actual lifting power and such, but oh how much better it would look. And as I don't play with my Lego models, I only pose them, I wouldn't care.

If I find the time and inspiration I'll try to mod the crane, taking it to the slim club, and post it in the modding thread.

[MaxSupercars]

I think that you're right about the crane but as you said you can anytime modify it... On the other hand I like it because it's probably the most important new part of the set and it's more imposant and maybe fits better in hands in this size... :)

Max...

Edited August 18, 2015 by MaxSupercars

[N-4K0]

The Norwegian web store lekmer dot no has a campaign with -20% on all Lego up until Monday. With that the Arocs is at about $192 instead of an average of $235 in general.

I really consider buying it, but I'm unsure because I only really want the bracket and pneumatic parts, maybe the buckets.

What would you recommend, guys?

Edited August 19, 2015 by Error404

[Brickthus]

I definitely recommend this set. My review is here

@tholmol: nice idea to shrink the crane. Need 2 more sets to get the 1/11 actuators! It will need to be strong even to carry the hoses, so I suggest you use more 3.2mm rigid tubes, as the original pneumatic truck 8868 did.

@Error404: Consider which pieces use a significant proportion of the value of the set (£170), based on customer services prices:

- Pneumatic parts maybe £50

- Wheels £34.56

- Springs £12

- Bucket, turntable, telescopic parts (10) £13

- Panels £25

- PF L-motor and battery box £18

Comes to £152.56. There is a discount for buying a set compared to individual parts.

I consider this sort of calculation when I'm buying sets, especially multiples. E.g. if you want the white panels then buying many of Cargo Plane 42025 is worth it - I bought 8!

Of course all the interesting parts from 42043 are out of stock, and I expect they will be till next year. The Mercedes badge might never be available as a single piece, or else it will carry a large franchise premium in its price!

Mark

[N-4K0]

Well, I'll see what I do.

[Leif]

It seems LEGO stopped giving us 12 tooth bevel gears as spare. When did it happen for the first time? Was that gear strengthened in any way?

We got so many spares from our previous sets so we don't need any more 12 bevel gears..at the moment..

[MaxSupercars]

MB Arocs B Model... you need only 33 bricks for easy motorisation... :)

Max...

[Saberwing40k]

Has anyone gotten their hands on the new pieces for 42043 via Lego Service? I just visited the site, and they say that they are out of stock. I've found them on Bricklink, but the prices are outrageous. Does anyone know if/when they will be available? Thanks.

[Emmi]

Is there a clever way to make the printed Mercedes Benz logo fit on the Unimog U400 instead of the sticker piece?

[JunkstyleGio]

Dude...

Edited August 22, 2015 by JunkstyleGio

[Emmi]

Getting to fit the Mercedes logo in nicely on the Unimog U400's grill isn't as easy as it would seem at first. It needs some tweaking, actually I took the grill apart two times before I was happy with the result.

Edited August 22, 2015 by Emmi

[N-4K0]

I don't know if it has been stated, but which piece is it that has the MB logo print? How is it attached to the truck, or in this case, the Unimog?

[MontyPython]

It's the shield piece.

[N-4K0]

Ok, thanks. I suppose it's attached with a simple 1x1 plate with clip on top or something.

Edited August 22, 2015 by Error404

[Milan]

1. Is 10e too much for a new long pneumatic cylinder?

2. Does anyone know how much it is (will be) online directly from Lego? Are pieces cheaper on BL or directly from Lego?

3. What is the tendency with the new parts regarding the price on BL? Go down maybe in a few months?

[Saberwing40k]

1. Is 10e too much for a new long pneumatic cylinder?

2. Does anyone know how much it is (will be) online directly from Lego? Are pieces cheaper on BL or directly from Lego?

3. What is the tendency with the new parts regarding the price on BL? Go down maybe in a few months?

1. Yes, $10 for a part plus shipping is a lot.

2. That's what I was asking to, but I don't think anyone has actually gotten them from Lego yet.

3. I would say so. I looked at some other recently introduced parts on Bricklink, namely the new 16z clutch gear, and the prices did indeed go down after a while. Unless the parts in the Arocs are exclusive to it, I see the same thing happening.

Fingers crossed that all of the new stuff in the Arocs, like the gear racks and brackets, and the cylinders in particular, get used in other sets.

[Emmi]

Ok, thanks. I suppose it's attached with a simple 1x1 plate with clip on top or something.

Not quite, you have to use two of these and press the shield between them (it makes click and works perfectly). If you only use 1 you can't place the shield in the middle of the grill, it's it then either too far on the left or right side.