[MOC] Rough Terrain Crane MKII

suffocation · April 8, 2019

This is my second rough terrain crane. My first one was a bit of a disappointment for me, mainly because of its boxy appearance. I know this one is far from eye-candy but I do think it's a step forward. This thread chronicles the painful gestation of my latest silliness.

Before rambling on any further, I'd like to thank all the folks who have gone out of their way to help me out with my clumsy, whimsical builds, especially @I_Igor and @Erik Leppen. Your poise, selflessness and creativity are exemplary.

The crane is entirely remote-controlled (2 x BuWizz for the carrier; 3 IR plus 1 LiPo for the superstructure) and features the following functions:

- 4x4 drive with planetary hubs (4 L motors geared down 11.2:1)
- 4 steering modes: front, rear, 4x4 and crab (2 servo motors)
- independent suspension
- synchronised two-stage outriggers (1 L motor)
- carrier lights (x1)
- fake straight 6 (spins at around 1130 rpm, much to my nephew's delight)
- boom lift (1 XL motor)
- boom extension (1 L motor)
- boom winch (1 L motor)
- superstructure rotation (1 M motor)
- cab tilt (1 M motor)
- superstructure lights (x3)

I borrowed a few ideas from 42082, namely the slewing ring and the cab. The boom is based on Gerger's Grove found elsewhere on this forum.

Other than that, I wanted the model to have lots of guts in plain sight, hence the front-mounted engine and the dozens of exposed gears. I also wanted some form of suspension that wouldn't compromise the model's longitudinal stiffness, so I went for an independent rather than a more realistic floating or pendular solution. In so many words, the model is less about realism and more about playability and durability.

As an added bonus, the superstructure can be easily removed and mounted on a 42055-style carrier, as seen below.

Comments, criticism and beer are welcome. Especially beer.

Edited April 10, 2019 by suffocation

1gor · April 8, 2019

Since we are not separated by street it is a difficult to go to beer, but as I already mentioned I'll help when I can and if I can not help I won't do any harm. It is very cool to see "modular" upper-structure :thumbup:

zoo · April 8, 2019

3 hours ago, suffocation said:

Especially beer.

To beer or not to beer, that is the question.

LEGO Train 12 Volts · April 8, 2019

Beautiful crane ...the second version with the tracks is a masterpiece! :wub:

Ngoc Nguyen · April 8, 2019

??????

nerdsforprez · April 9, 2019

12 hours ago, zoo said:

To beer or not to beer, that is the question.

Or, after several beers, the question might be better stated "too beare or.....not.... two beeare, aaaahhh that is thee qwuastrion" :drunk: :drunk:

Really great model. I liked the other version as well, but the improvements here are notable.

Magical Duck · April 10, 2019

Both of your cranes are functionally very sound, but I like this one especially! Excellent work- I think you should be proud. :wub:

suffocation · April 13, 2019

On 4/8/2019 at 5:36 PM, I_Igor said:

Since we are not separated by street it is a difficult to go to beer, but as I already mentioned I'll help when I can and if I can not help I won't do any harm. It is very cool to see "modular" upper-structure

If you're ever travelling through northern Italy hit me up and we can indulge in my speciality, Pasta alla Norma! :moar:

On 4/8/2019 at 7:44 PM, zoo said:

To beer or not to beer, that is the question.

Always beer :drunk:

On 4/8/2019 at 9:50 PM, LEGO Train 12 Volts said:

Beautiful crane ...the second version with the tracks is a masterpiece!

Grazie mille! :drunk: (wielding a bottle of Sagrantino di Montefalco here)

On 4/8/2019 at 11:39 PM, Ngoc Nguyen said:

??????

More beer! :drunk:

On 4/9/2019 at 8:15 AM, nerdsforprez said:

Or, after several beers, the question might be better stated "too beare or.....not.... two beeare, aaaahhh that is thee qwuastrion"

Really great model. I liked the other version as well, but the improvements here are notable.

Thank you! The previous model had quite a few shortcomings, so improving was easy :laugh:

On 4/10/2019 at 2:33 AM, Magical Duck said:

Both of your cranes are functionally very sound, but I like this one especially! Excellent work- I think you should be proud.

Thank you! Not proud, but definitely toasting a few times too many :drunk: :drunk: :drunk:

zoo · April 13, 2019

3 minutes ago, suffocation said:

Always beer

But of course! :drunk:

n7zhang · May 17, 2019

nice build, have you considered adding a secondary hook?

suffocation · September 15, 2019

Rebuilt the carrier using the planetary hubs from 42099 and the yellow racks from 42097. I also switched from four springs per wheel to two springs and a torsion bar: the suspension is much more responsive now but doesn't sag under the model's ridiculous weight.

On the downside, I realised the model was really struggling to steer with 120 mm RC tyres, so I switched to Claas tyres and rebuilt the mudguards using the wheel arches from 42070 (and a million other sets) to kind of offset the visual impact of the smaller tyres.