Hi guys,

as I've currently passed a road construction site, I had a glimpse of a machine I've never saw in this very configuration. As I reserached for this Mecalac 12MTX, I was so impressed about the versatility, especially the boom, I just had to build it. 

The 42122 Jeeps tires fit so perfectily here (down to the exact number of 16 ribs), the scale was already set in my mind. The length of the availabe 1 stud wide pneumatic arms just didn't match quite well, so I am now tinkering with The geometry of the curves however is very hard to recreate with only technic panels, so I had to move to system pieces. As I already did my Liebherr L518 in yellow and DBG, I know selected black, but maybe switch back, what do you guys think? 

Here is the current state:

Edited September 9, 20222 yr by Jundis

Wow, this thing looks weird. Like some sort of ant or other insect.

But ot looks like a very nice start 

Looks good so far. Mecalac machines are pretty cool and it's great to see someone take one on as a Technic build. Looking forward to seeing more. 

Cool project, looks very promising! Looking forward to the next update 

I'm really digging this.. good call on the system pieces.. 

my vote goes to yellow and dbg. itll match nicely with the liebherr and the lbg linear actuators will stick out a lot less.

Edited February 18, 20223 yr by arieben

Thanks for the comments, guys!

11 minutes ago, arieben said:

yellow and dbg.

I just tried in stud.io and many pieces are limited to black, Panel#1/2, the flip-flop liftarm and 2x3 extension panel for the front support :-/

Cool project! 

A lot of functions packed in a small sized model is really challenging, looking forward to see the progress ;-)

Love how it's coming along! Really well done on seamlessly blending the studded and studless parts.

Good luck with all boom possible movements.

Oh boy, that brings back memories...

Although it was an older version. It's a fascinating machine, for sure.

Second @Jurss, very interested how you will do the boom. The vertical articulation point gave me a lot of "fun"

Edited February 18, 20223 yr by proran

Very cool project. I like what you have so far, and the boom is looking great. I don't have any problem with the system parts. 

1 hour ago, proran said:

Oh boy, that brings back memories...

I remember that very well - more than five years later I'm still in awe at your design.

18 hours ago, proran said:

Oh boy, that brings back memories...

Although it was an older version. It's a fascinating machine, for sure.

Second @Jurss, very interested how you will do the boom. The vertical articulation point gave me a lot of "fun"

I didn't know anybody did this before, very cool and waaaay more complex than my attempt! Just whoa!

The plan is to try the vertical articulation, but I have no problem to skip this, when it seem too wobble in this scale.

Very nice machine and clever first steps. I like the boom linkage like some wheel loaders use with the bucket but it is very bad for us because it is imposibble to do it RC, but your manual way is perfect.

I hope it all works out well for you. I made one some years ago on a larger scale, but the boom geometry was a bit of a challenge, as well as the offset boom. Maintaining proportionately scaled parts becomes more of a challenge with the smaller model.  There are numerous pivot points in the real machine which require maintenance or else the entire boom can exhibit much play, these become a greater challenge in Lego.  You have made a good start.

On 2/19/2022 at 9:39 PM, jorgeopesi said:

Very nice machine and clever first steps. I like the boom linkage like some wheel loaders use with the bucket but it is very bad for us because it is imposibble to do it RC, but your manual way is perfect.

Thanks Jorge! Acutally I followed your "keep-it-simple" principle here. There is just so much going on.

On 2/20/2022 at 2:47 AM, trekman said:

but the boom geometry was a bit of a challenge, as well as the offset boom.

Certainly, I will use a counterweight, as the extended boom will give such a big moment of force onto the whole chassis.

I tinkered around various solutions but the more complex they become, the less I liked them. It just got too bulky, so I settled with a simple solution: Small LAs, just activated by a gear on top. I got nearly the same range as the real model:

The main boom with the flip-flop beams will be made a bit beefier with few system pieces (slopes on the back side). same with the middle boom.

You are missing now that main interesting function of boom, which Mecalac has.

It looks very good and it will be a very good machine to train fingers  .

3 hours ago, Jurss said:

You are missing now that main interesting function of boom, which Mecalac has.

Still working on it, but if I can't do it with enough stability, then this function will be dropped. Right now my solutions would either be too bulky (small turntable, small LA) or to unstable/wobbly (pin-connection, friction-held only).

3 hours ago, jorgeopesi said:

It looks very good and it will be a very good machine to train fingers  .

That's true :D
But the mechanism for the main boom is so satisfying to activate. :-)

The range of motion achieved with small LAs is pretty impressive imo 

1 hour ago, Jundis said:

But the mechanism for the main boom is so satisfying to activate. :-)

I could not agree more I have to copy it to can have fun a little.

Great updates. It's looking better and better. I like the range of motion for the boom, and the tires really look great on this.

Keep it up!

I really tried hard coming up with a solution for the vertical tilt of the middle boom section. Sadly, there is no easy way of implementing this feature in a good looking and functional manner. Here are both types in a half baked state. I also build both, but they quickly got too clumsy (wormgear) or too unstable (small LA). I decided to move on with the main build, maybe an idea for the boom will appear during a creative phase :D

Just make it relaying on some pin friction.

Yeah, that and two of these.