42128 B Model - Dump Truck

[Ngoc Nguyen]

 

Miss out on the 42043? Don't wanna spend 400$ on a new one?

Have no regret. The second coming of 42043 is here. Spend 150$ on a new 42128, and build yourself a smaller version of 42043 with all the functions and details faithfully replicated. Better yet, sell all the pneumatics to recoup the cost!

Functions: 

- Twin drive rear axles
- Inline 6 engines
- Twin steer front axles with different radii
- HOG steering
- Cabin tilting
- Openable doors
- Linked 4 outriggers
- Dumping bed
- Openable and lockable tail gate 
- Crane slewing
- Crane's 1st section raising
- Crane's 2nd section raising
- Crane's 3rd section extending
- Winch 

 

Essentially all the cool functions of 42043, minus the suspension, motorization, and pneumatics. The lack of pneumatics is both a good thing and maybe a bad thing. It's a good thing because if you want to buy this set only for the pneumatics, you can use the remaining parts to build something nice. It's maybe a bad thing because the 42043 has pneumatics and this model doesn't. The reason for no pneumatic is simply that there's no space. 

All the details from of 42043 are replicated: 

- Modular build
- Side mirrors
- Additional two mirrors on passenger's side
- Horns
- Antenna
- Hazard lights
- Aerodynamic roof fairing
- Wheel chocks
- Tow hitch in the rear 

And additional niceties:

- Screen wipers
- 3 pedals under the steering wheel with different shapes
- Aircon slits on dashboard
- Cup holders on dashboard
- Adjustable arm rests on chair
- Adjustable back rests on chair
- Adjustable head rests on chair
- Bed with pillow and blanket
- Table and drawer under the bed
- Overhead shelf
- Fuel tanks
- Oil filters 
- Cabin prop bar

More photos:

 

 

 

 

 

 

 

There is no demonstration video because I don't have professional settings and devices. If anyone can make a quick review of this set and provide me with a demonstration short clip, I'd be very grateful.

Free instruction: https://rebrickable.com/mocs/MOC-84354/nguyengiangoc/42128-b-model-t-face-mc-t-truck/

Edited September 29, 2022 by Ngoc Nguyen

[Scoar Sonander]

Wow! Surprised how quickly a B-Model has been constructed, with this much quality and functions! Great job and good usage of the "limited" parts !

Also... First! 

[Mr Jos]

46 minutes ago, Scoar Sonander said:

Wow! Surprised how quickly a B-Model has been constructed, with this much quality and functions! Great job and good usage of the "limited" parts !

Also... First! 

Second! Hope this topic gets more comments.. (Already ∞ more now) As I know how hard it is to make a B model (limited parts).

To your model selve now, good size, and aesthetics, just to bad you didn't find place for the pneumatics, they are to me what Lego made so interesting when I was a kid. If I were you I'ld still try to get the 1x11 cylinders in somewhere, they don't need so much space, the 2x11 however I can understand. They are very bulky. If I fail at my C Model, I'll break it down and give your instructions a try.

[Ngoc Nguyen]

7 minutes ago, Mr Jos said:

If I were you I'ld still try to get the 1x11 cylinders in somewhere, they don't need so much space

It doesn't, but a pump and a valve do . Especially the pump. As you can see from all angles there's no space for it.

Besides, the crane doesn't have a 11 stud space for a cylinder. Of course I can do a straight boom crane like the one in the original 42043, but that wouldn't be challenging enough for my taste. Designing a mechanical side-fold knuckle boom is a much much harder task that I struggled with, but I solved it eventually, and enjoyed that journey.

Edited August 10, 2021 by Ngoc Nguyen

[Mr Jos]

9 minutes ago, Ngoc Nguyen said:

It doesn't, but a pump and a valve do . Especially the pump. As you can see from all angles there's no space for it.

Yeah the pump is really huge, a small 1x6 pump is way easyer to find place for then this 3x3x11 chunk, it's the reason I left out a seat for the driver. Certainly in small builds it's hard to get these items in, but in big builds the pneumatic 'action' length is pretty small if you compare it to gear racks, which can go on forever. Most things I can think of using hydraulic cylinders in real, would have a way to short movement with these Lego cylinders.

Edited August 10, 2021 by Mr Jos
size correction

[suffocation]

Amazing work, especially with the limited parts and in so little time

[whitepen]

This is awesome! I will have to build it when I get this set! 

[dvm]

Great job, thanks for sharing the instructions.

In case anyone was hesitating to buy the set...

[Rebel_Lego]

Great model! The front doesn't look too good (but still good) but I guess that's just part limitation. And many thanks for free instructions!

[Ngoc Nguyen]

2 hours ago, Rebel_Lego said:

Great model! The front doesn't look too good (but still good) but I guess that's just part limitation

Yes, the model turns out to be more restrictive than it appeared at first. I wanted to save the parts for the cabin interiors, the crane, and the bed, so I just went for some generic truck front, and incorporated a number of design choices from the 42098 cabin.

[Lakop]

Great B model. I love the crane.

 

[Ngoc Nguyen]

A user uploaded some nice looking photos of this B model on Rebrickable.

 

 

 

[Ngoc Nguyen]

The first version that I published contains several problems:

- The wheels of the first axle rub into the steering linkage.
- The steering linkage is not strong enough to steer the first axle, so when the HOG steering knob is turned, the second axle will steer but the front one doesn't.
- The bottom ends of the exhaust pipes actually collide with the bent 7-3 orange liftarms. I didn't discover this until I returned to this model and redesigned the steering.
- The doors can't open fully because the connections for the mirrors get in the way. There are other parts that are not problems but can be improved:
- The model can't be picked up easily because all of the upper modules (cabin, crane, bed) are not firmly attached to the body.
- The building sequences of the cabin and crane aren't very clear. - The part of the chassis of the crane isn't adequately supported.
- The rear outriggers aren't firmly connected.

 

So I started working on this set again to fix all of the problems above and some other tidbits. The result is a much better version.
- I added another layer of gear reduction and properly braced the rear outriggers. They work perfectly now.
- I added the linkage on both sides of the front axles to prevent the lack of steering of the first axle.
- I moved the linkages one stud upward as well as added limiters to prevent the front wheels from rubbing.
- I added supports in the chassis part under the crane.
- I turned the cabin and crane into separate and easily removable modules.
- I added cabin locks behind the mudguard. The truck can be lifted by the cabin now.
- I moved the connections for the mirrors one stud backwards. The doors can open more widely now.
- I lifted the exhaust pipes one stud upward to prevent the collision with the orange 7-3 liftarms.

 

I also made a proper render.

 

If you have built the first version, I strongly suggest that you rebuild parts of the models according to the new version. You will have a much better model to play with!

[Ngoc Nguyen]

I have some better photos posted by a builder on Rebrickable.

 

 

 

 

 

[jacabias]

Seeing this topic updated reminds me that I have been wanting to build this; I was actually thinking about it either this morning or yesterday! I had missed that there is an updated version of your model, so I will be careful to redownload the instructions.

[30somethingkid]

What a shame. I missed out on the instructions being free! Feeling very light walleyed atm. I've not bought anything for a year!