[WIP] All terrain crane

[Erik Leppen]

Since 42082, I'm seeing a few all-terrain crane MOCs on the forums, and I thought, it's something I haven't built yet and it sounds like a fun challenge, so I thought I'd give it a try as well. I'll be using the same wheels as 42082, so the scale is similar, but I'm not basing my model on a specific real-life model.

Here's the first WIP:

The base is as short as possible given the wheels and turntable ring. The wheelbase is 2 studs shorter than 42082, which I think is good. It is a bit wider though, but this is needed to accommodate the steering modes.

As you can see, its a bit of a weird color combo. As I only have the banana gears (11x11 quarter-circle gear racks) in yellow, I'm kind of stuck with that color, so I decided to use yellow for the wheels too. As I find yellow by itself a boring color for a crane, I tried to find a second color to match with it that's preferably not red or black or gray. I think orange is unusual enough, and also readily available in my collection. I think, like with 42082, I'll be using black as a filler color.

I want to do a similar setup with motorization as 42082: have one motor and a switchbox in the superstructure, and control at least the following functions:

• boom up/down
• winch
• boom extend
• superstructure swivel
• outriggers (one degree of freedom)

Also I want the following manual functions:

• outriggers (second degree of freedom)
• fake engine
• steering (with steering modes as in 42054)

I copy the same mechanism 42054 uses for the steering modes. So that won't be very original, but it proved hard to squeeze it in the rather limited space available.

The bottom view shows there's no center diff. I don't think it's needed. Also, there is no suspension.

Also, as the steering selector is in the rear, I expect the V8 fake engine to take place at the front.

Here's a top view without the wheel arches and turntable ring, that hopefully shows the steering linkage. The black beam that slides on the two parallel yellow axles is the steering mode selector. The 24t gear on top controls the steering, through the turntable. This means that the outriggers wll have to be the second function to go through the turntable.

The long red axle sticing out the left runs all the way through to the right and will conect to the outriggers.

Also, I want to make sure there is a large ground clearance. I hope this side view image shows a bit of that. Also i focused on having a simple strong chassis, which is basically a 5-stud-high box of parallel long beams (13 + 15 + 13) connected by 5 x 7 frames and dogbones. It's a bit hard to see with all the black though. Also I tried to make a strong base for the turntable ring (see above).

I think the last bit of interest is the outriggers module. I wanted something that's a bit different, and I know there are cranes with angled outriggers, so I tried to recreate that.

I think it looks quite cool and unique. It's not an exact fit, but it works well enough. The idea is that the extending with the gearracks will be motorized, and some kind of footer at the end will be manual.

The red axle drives the whole thing. The 8 red bush-pins connect the module to the chassis. I hope to keep it a modular build like this.

 

Next steps will be the base of the superstructure, and see if I can find a way to add the motor and switchbox.

[ludov]

Interesting build, as usual from you. I’ll be following this. I’m curious to see how see how 4x4 drive works with the 3 steering modes. I’d think you need a center diff for the normal mode (2 wheel steering), but I might be wrong.

Did you abandon the other crane?

[BrickbyBrickTechnic]

Few pointers from someone who has already done this:

- Find a place for the steering shifter fast. It proved to be the hardest thing to find pace for when I built mine, and it greatly impacts how well the steering actually works since you're using the 42054 mechainsm.

- Make sure the core of your chassis is extremely robust. If it can bend even a little, when the superstructure is to the side, it will.

- Make it modular. This makes it soooooo much easier to diagnose problems.

- Add an engine if you can. it seems you have some place.

Overall amazing WIP, I can't wait to see how it goes!

[1gor]

Outriggers are really original, and I like simple and sturdy chassis build. Real one does not have central differential and no portal axles, so I prefer your design. 

[Erik Leppen]

59 minutes ago, Ludo Visser said:

Interesting build, as usual from you. I’ll be following this. I’m curious to see how see how 4x4 drive works with the 3 steering modes. I’d think you need a center diff for the normal mode (2 wheel steering), but I might be wrong.

Did you abandon the other crane?

Technically I think you're right about the center diff. However I think it does make things more complicated, and I don't see the space for it right now.

55 minutes ago, BrickbyBrickTechnic said:

- Find a place for the steering shifter fast. It proved to be the hardest thing to find pace for when I built mine, and it greatly impacts how well the steering actually works since you're using the 42054 mechanism.

This is good to know!  Thanks for the advice (as well as your other points (not quoted)) I think I place it somewhere where normally he V8 would go, and put the V8 above the front axle. It's not ideal, but I think from a Lego model perspective, it's the most sensible option. Also good point about the sideways bend, even though a large lift capacity is not one of my wishes. It remains to be seen how long and heavy the boom will be. As for modularity: the outrigger sets will be easily separable, and the superstructure is also an obvious one to make modular.

50 minutes ago, I_Igor said:

Outriggers are really original, and I like simple and sturdy chassis build. Real one does not have central differential and no portal axles, so I prefer your design. 

Thanks :)

[jorgeopesi]

I like the outriggers too is the best way to elevate a machine without big pistons. I like the upper view of the central part too.

[1gor]

About engine, I prefer inline 6 and not V8...

[BrickbyBrickTechnic]

2 hours ago, Erik Leppen said:

Also good point about the sideways bend, even though a large lift capacity is not one of my wishes

This happened without there even being any load (so just the superstructure) so either it's something to watch out for or my chassis was super weak

[coinoperator]

Is it me or ae the pictures that were posted bij de TS invisible?