42146 - Liebherr LR 13000 MODs and Improvements

[Ngoc Nguyen]

3 minutes ago, Bubbha said:

Hi, thank you for your reply, i was thinking to use XL motors for drive and rotating boom due to it's torque and slower Speed (the boom rotation Is too fast for a Crane like that). There are many empty parts in the structure, maybe it's tricky to keep It strong as It Is now, placing all the gears inside.

For the overstructure, i would try to use One XL with a gearbox that switch between the three functions.

For now, i have to finish the set, but i'm sure i'll be tired of c+ soon.

Anyway, big thanks for your help.

 

Im not sure if I remember correctly, but PF L and PF XL have the sane torque output. What makes L easier to use is that its form factor allows it to be integrated more easily into existing structure. To accomodate an XL you effectively need to clear out a 5x5 space.

[Bubbha]

9 minutes ago, Ngoc Nguyen said:

Im not sure if I remember correctly, but PF L and PF XL have the sane torque output. What makes L easier to use is that its form factor allows it to be integrated more easily into existing structure. To accomodate an XL you effectively need to clear out a 5x5 space.

According to filohome site, XL motors has 4x more torque than L motors. That's why i tought to use that, even if it's volume can be more difficult to place inside.

[bruh]

It actually has only 2x according to his website. It has 4x the output of the medium motor.

[Bubbha]

5 hours ago, bruh said:

It actually has only 2x according to his website. It has 4x the output of the medium motor.

Yep, i confused M and L.

XL has still the higher torque.

[bruh]

Yeah. More torque = more better!

[KeithDotBike]

Kudos to @Marno,  @Minitiguan, @Legotom, @R0Sch, @riverprawn  for sharing your MOCs. I went for an extra two box sections in the main boom. Doesn’t make it match the real thing, but it’s an easy way to improve the proportions. 

With reference to the iconic Liebherr 2012 product demo, it’s lifting another crane - set 855 that I got in 1977. My newest technic set lifting my first ever technic set! Technic’s come a long way in almost 50 years: 

Unfortunately I don’t have the time for any major mods - but that rotation gearing needs reducing!

 

Edited January 18 by KeithDotBike
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[Minitiguan]

Inspired by @vanczakp and his V-Frame idea, I build another one for my moc. 

I want to design the "V" in the back section and use two actuators, instead of one.

Because my crane most of the tine stand on a shelf, I decided to use a manual mode and not a motorized one (I had also no idea how to combine / add another motor in the original Lego app  )

 

Edited January 19 by Minitiguan

[Chrizl]

On 1/19/2025 at 4:02 PM, Minitiguan said:

Inspired by @vanczakp and his V-Frame idea, I build another one for my moc. 

I want to design the "V" in the back section and use two actuators, instead of one.

Because my crane most of the tine stand on a shelf, I decided to use a manual mode and not a motorized one (I had also no idea how to combine / add another motor in the original Lego app  )

 

 

 

 

Love that V Frame....do you have more details or instructions how to rebuild it?

[Minitiguan]

@Chrizl, I am selling this instruction on Kleinanzeigen ;-)

Edited March 6 by Minitiguan

[Piggie12]

On 12/6/2023 at 10:49 AM, Lego Tom said:

Let there be light!

@Lego Tom Those light look great! I was thinking of installing some lights myself into the non-modded version as well since I can't find a lighting kit online. Did you buy all the lights separately or did you use a standard lighting kit? Thanks for any info!

[Lego Tom]

11 hours ago, Piggie12 said:

@Lego Tom Those light look great! I was thinking of installing some lights myself into the non-modded version as well since I can't find a lighting kit online. Did you buy all the lights separately or did you use a standard lighting kit? Thanks for any info!

I bought them separately.

[Bartybum]

So I've been looking at alternatives to the standard four-panel boom, namely because a single segment costs like $15-20AUD  and I think I've come up with something that could work. I'd be interested if anyone could build a couple and test how rigid it is. Overall I'm pretty happy about it, but man would things be so much easier if only we had 3L and 5L liftarms with friction pins sticking out at either end, in the same manner as part 15100. I think CaDA has them in fact. The clutch strength of the 15100 pin connector can be annoying, but it's perfect for this application to stop the chords from getting pulled out. A round 3L connector would simplify things a great deal here too.

Moving on, however, the first challenge I've tried to address is torsional rigidity. I've done so with the help of the trusty 5x7 frame and a double-pinned connection to the chords (the long straight segments). What this achieves is that it rigidly fixes the chords to the 5x7 frames, so that there's no local rotation of the connection. I've explored both orientations of the 5x7 frame, both shown below. I'm only confident in the horizontally oriented one, namely due to its neat connection to the chords. Having the frame oriented vertically is possible, but the arrangement of parts is messier in comparison.

The second challenge has been to maintain a similar aesthetic to the real crane's truss segments, at least from the side where the appearance is most visible. This means having crossbeams only at either end of each segment, with diagonal braces running down the side. Because of there only being one Pythagorean triple aesthetically practical for this 7-stud deep truss - (6,8,10), or a 7L*9L*11L liftarm triangle - the length of the truss segment has approximately doubled to 33L vs the original's 15L. This has actually worked out nicely, since it better matches the proportions of the segments in the real thing.

Since there's obviously no 33L liftarm in the Technic parts catalog, so I've split the chords up into three parts, in this case 7+15+11, with 5L liftarms connecting each part. I'm slightly worried the 5L connection may be too short, so if anyone builds this I'd also be interested to see how rigid it is with 7L instead. It'd be interesting as well to see how the flexibility of the black 2L pins affects the axial stiffness of the chords, and to what extent it increases bending of the overall truss.

Final weight comes out to be ~110g, versus 93g for two of the original four-panel truss segments, so about a 20% increase in mass.

Something I'm a bit apprehensive about is the rigidity against lateral skewing, especially since I've forgone any diagonal braces along the top and bottom surfaces.

In any case, pictures !!

The first is with horizontally oriented 5x7 frames, and its connection to adjacent segments:

 

Second is the vertically oriented 5x7 frame:

 

Would be very interested in any feedback :)

Edited July 11 by Bartybum

[howitzer]

4 hours ago, Bartybum said:

So I've been looking at alternatives to the standard four-panel boom, namely because a single segment costs like $15-20AUD  and I think I've come up with something that could work. I'd be interested if anyone could build a couple and test how rigid it is. Overall I'm pretty happy about it, but man would things be so much easier if only we had 3L and 5L liftarms with friction pins sticking out at either end, in the same manner as part 15100. I think CaDA has them in fact. The clutch strength of the 15100 pin connector can be annoying, but it's perfect for this application to stop the chords from getting pulled out. A round 3L connector would simplify things a great deal here too.

Moving on, however, the first challenge I've tried to address is torsional rigidity. I've done so with the help of the trusty 5x7 frame and a double-pinned connection to the chords (the long straight segments). What this achieves is that it rigidly fixes the chords to the 5x7 frames, so that there's no local rotation of the connection. I've explored both orientations of the 5x7 frame, both shown below. I'm only confident in the horizontally oriented one, namely due to its neat connection to the chords. Having the frame oriented vertically is possible, but the arrangement of parts is messier in comparison.

The second challenge has been to maintain a similar aesthetic to the real crane's truss segments, at least from the side where the appearance is most visible. This means having crossbeams only at either end of each segment, with diagonal braces running down the side. Because of there only being one Pythagorean triple aesthetically practical for this 7-stud deep truss - (6,8,10), or a 7L*9L*11L liftarm triangle - the length of the truss segment has approximately doubled to 33L vs the original's 15L. This has actually worked out nicely, since it better matches the proportions of the segments in the real thing.

Since there's obviously no 33L liftarm in the Technic parts catalog, so I've split the chords up into three parts, in this case 7+15+11, with 5L liftarms connecting each part. I'm slightly worried the 5L connection may be too short, so if anyone builds this I'd also be interested to see how rigid it is with 7L instead. It'd be interesting as well to see how the flexibility of the black 2L pins affects the axial stiffness of the chords, and to what extent it increases bending of the overall truss.

Final weight comes out to be ~110g, versus 93g for two of the original four-panel truss segments, so about a 20% increase in mass.

Something I'm a bit apprehensive about is the rigidity against lateral skewing, especially since I've forgone any diagonal braces along the top and bottom surfaces.

In any case, pictures !!

The first is with horizontally oriented 5x7 frames, and its connection to adjacent segments:

 

Second is the vertically oriented 5x7 frame:

 

Would be very interested in any feedback :)

Looks good from the pictures, I'll see if I have time to do a test build during the weekend. Shouldn't be too hard but takes a bit of time to make multiple segments. Could you make a parts list for easier building?

[Bartybum]

3 hours ago, howitzer said:

Looks good from the pictures, I'll see if I have time to do a test build during the weekend. Shouldn't be too hard but takes a bit of time to make multiple segments. Could you make a parts list for easier building?

Sure thing, see below :) The two parts lists are, in order, the horizontal 5x7 frame configuration, followed by the vertical 5x7 frame configuration.

The short axles are 3L and the long are 7L. Both configs use a variety of 5, 7, 11 and 15L liftarms.

[howitzer]

6 hours ago, Bartybum said:

Sure thing, see below :) The two parts lists are, in order, the horizontal 5x7 frame configuration, followed by the vertical 5x7 frame configuration.

The short axles are 3L and the long are 7L. Both configs use a variety of 5, 7, 11 and 15L liftarms.

 

 

Thanks! I'll try this out tomorrow when I have free time!

[howitzer]

So I built 2 sections of each, sorry about the vomitous mass of colours.

Upper one is the vertical variant (second in @Bartybum's post) and lower is the horizontal variant. They seem to be equally strong but the horizontal variant was much less annoying to build so I'd prefer that if I were to use these in an actual MOC.

They seem to be strong in the direction where diagonal supports work, but less so in the other direction, bending quite easily. The problem seems to be the fact that there's pinholes supporting the structure against bending (either with axle or pin inside) and that gives the chords at the section joint too much play; the middle of each section is stronger (having double pins in each liftarm joint). Also, like Liebherr booms, there's nothing to stop them pulling apart laterally which might contribute to their bendiness.

The other problem is torsional rigidity, which is much less than that of the new boom parts in 42146. I think the reason is the lack of diagonal supports in one direction, combided with the play every pin connection inevitably has. In the end it probably comes down to the fact that large solid parts are stiffer and stronger than POOP builds of similar shape and purpose.

One thing of note is also that the sections are much longer than the boom sections in 42146, with two of these sections being slightly longer than the 4-section main boom of the Liebherr. I think this could be solved by building separate end section where necessary though.

My above analysis might seem quite critical but still I think these are perfectly usable as crane booms, as long as the crane isn't being used to actually lift very heavy loads relative to its height. The horizontal frame variant was easy enough to build and all of the parts are plentiful and cheap so they might very well work as an alternative to the Liebherr parts. Though if you want some serious lifting capacity, the Liebherr parts are a better option.

[Bartybum]

5 hours ago, howitzer said:

My above analysis might seem quite critical but still I think these are perfectly usable as crane booms, as long as the crane isn't being used to actually lift very heavy loads relative to its height. The horizontal frame variant was easy enough to build and all of the parts are plentiful and cheap so they might very well work as an alternative to the Liebherr parts. Though if you want some serious lifting capacity, the Liebherr parts are a better option.

Thank you very much for the feedback! Don't worry at all regarding your critique - that was the very reason I wanted someone to try it out.

There are a couple things I'll iterate upon based on your comment, but I think I'll do that on my end at some point soon, just need to pull down a bunch of heavy boxes lol (also one of the reasons I wanted someone else to build it , so thank you again for being my test guinea pig).

Edited July 13 by Bartybum

[howitzer]

7 hours ago, Bartybum said:

Thank you very much for the feedback! Don't worry at all regarding your critique - that was the very reason I wanted someone to try it out.

There are a couple things I'll iterate upon based on your comment, but I think I'll do that on my end at some point soon, just need to pull down a bunch of heavy boxes lol (also one of the reasons I wanted someone else to build it , so thank you again for being my test guinea pig).

Thanks, keep us posted on your progress!