[WIP] LIEBHERR LTR1100 Crane

[Kit Fisto]

Hi guys! 

I'd like to share with you the project that has been sitting in my head for sooooo long - and I finally started it some weeks ago - LIEBHERR LTR1100 Crane.

One of the main features of this crane that I wanted to re-create in Lego is extension of the tracks. What is more, they should be able to carry the load of the upperstructure while being extended.

What I have for now is fully working chassis.

Some specs:

Drive: 2 L-Motors geared down 1:24. A little bit too slow, but it's not a racing bolid, so I'm ok with that . On a serious note, it was the most compact solution I could find.

Tracks extension: 2 M-motors geared down 12:20. Current setup allows the tracks to extend with 2kgs load on the top of the chassis.

Remaining space between the tracks will be filled with battery box and 2 IR-receivers (the chassis and upperstructure will be 2 separate models withe their own BB's and receivers, no wires going through turntable).

As for the upperstructure, it will inlude 3-stage telescopic boom made of technic-panels to make it as light as possible, cause every added pound matters due to the load on the tracks. I forgot to mention that it will be a model-team style model, so, the other part of the upperstructure will me made of system parts.

The chassis:

Drive motor(this part was a real headache actually and I can say I'm really proud of this solution):

Extended position:

Track side view (Note that it might seem small, but the length of the track is 40 studs); also you can see suspension with very little travel here:

The bottom view that shows how everything is put inside together (T-Bone beams are used on the sides to mount M-motors and LA's that extend tracks).

Some size comprassion:

At the moment I'm trying to figure out the best way to make the 3-stage boom.

This is the current setup(3x11x1 panes should be black, curved panels - yellow):

Some words about the boom:
First of all, it will be long. VERY long. I've carefully calculated scale and it has to be 66 studs long(The 1st stage). Being made of techinc-panels, it will be light, so not a big problem. It will be raised either with stacked old-style pneumatic cylindrs, or with custom linear actuator. Not sure at the moment.

Secondly, I need your opinion.

I've browsed some crane mocs(with 3 and more stage booms), and it seems like none of them use gears to extend the 2nd stage. 

The solution I use on the picture above allows to extend and retract boom in any position (raised or lowered), but is it that important? I.e, if I use string-based extension of all boom stages including the 2nd, it will only be able to retract in the raised position with gravity and I'm really not sure what method to use.

The real machine:

I'm looking forward to all your comments and opinions 

 

 

 

 

 

Edited August 17, 2018 by Kit Fisto

[Aventador2004]

Good start, but the boom definitely needs work. Try researching the 42009 boom. It can give you some ideas.

[Erik Leppen]

At first I thought: it looks the base is too elongated, not "square" enough, to work as a base for a crane. But then I noticed it's extendable. A function I can't remember having seen before. Nice! Also, I like the good combination of studded with studless in the base.

For the boom, I undestand it is in very earily stages, but be sure to add vertical bracing near the end of the outer boom. This is needed when the boom is extended, to prevent gravity on the second section from bending and tearing the end of the main boom apart. So be sure to add some vertical beams between the panels somehow to keep it together.

For raising the boom: if you're going pneumatic, I'd recomend using the newer 2x11 cylinders, because they have longer reach than the old version. (6 studs vs. 3.5 for the old. That's quite a difference). Then you can use them 2 by 2, in the same style as 8460 but doubled up. Of the pneumatic solutions, I think that would be the best setup.

[Aventador2004]

3 hours ago, Erik Leppen said:

 A function I can't remember having seen before.

I believe @Sariel used it here:

 

Edited August 18, 2018 by Aventador2004
Sued: used?

[pleegwat]

4 hours ago, Erik Leppen said:

For raising the boom: if you're going pneumatic, I'd recomend using the newer 2x11 cylinders, because they have longer reach than the old version. (6 studs vs. 3.5 for the old. That's quite a difference). Then you can use them 2 by 2, in the same style as 8460 but doubled up. Of the pneumatic solutions, I think that would be the best setup.

I don't think you can put the new pneumatic cylinders back-to-back the way you can the old ones from the studded era. However with the amount of extra reach the new cylinders get you using the old ones for back-to-back action may not be worth it.

[M_longer]

6 hours ago, Erik Leppen said:

A function I can't remember having seen before

Like this?