[TC29] Liebherr R 926 compact excavator 1:21

[crazy technic]

here's my submission to this competition, I decided on a  compact excavator by liebherr., as it's the perfect candidate for this, it's: compact, has many functions and most importantly tracks :)

here's a first attempt at a undercarriage, it has track tentioning using shock absorbers, 2 motors for drive, 2 motors for other functions, currently I have a gearbox planned for the supperstructure.

I have exams coming up so I will only digitally design it at this moment, later I will do the physical design.

 

and here's the real one

 

[Auroralampinen]

Looks great so far:).

[crazy technic]

11 minutes ago, Auroralampinen said:

Looks great so far:).

thanks, I think it will get even better, Im not sure yet if I will use pneumatics or linear actuators

[1gor]

Do you plan to have all functions to be motorized? If so you need additional hub / battery box in upoer carridge...and better use actuators with motorizstion.

BTW looks good; a while ago I was thinking about blue wheeled version (I saw it on my way to work)....but I'll see. Perhaps I got some interesting idea from you...

[crazy technic]

4 hours ago, 1gor said:

Do you plan to have all functions to be motorized? If so you need additional hub / battery box in upoer carridge...and better use actuators with motorizstion.

BTW looks good; a while ago I was thinking about blue wheeled version (I saw it on my way to work)....but I'll see. Perhaps I got some interesting idea from you...

yes, all( or at least the most important ones) will be motorized, the contest only allows 4 motors, so I will have to use a gearbox for more functions, motorzed pneumatics are also posible, I just did it for a secret project that's 99% finished, but 5/6 pneumatic motorized functions will definitely be hard, even if I would use linear actuators it would still be difficult

 

[1gor]

1 hour ago, crazy technic said:

yes, all( or at least the most important ones) will be motorized, the contest only allows 4 motors, so I will have to use a gearbox for more functions, motorzed pneumatics are also posible, I just did it for a secret project that's 99% finished, but 5/6 pneumatic motorized functions will definitely be hard, even if I would use linear actuators it would still be difficult

 

Sorry I forgot about 4 motors...indeed gearbox would be complicated in such narrow space

[crazy technic]

I already have almost finished the gearbox the superstructure rotation is already connected. now I need to decide if I will use pneumatics or linear actuators

[1gor]

I would go with actuators because they enable smoother operation...

[crazy technic]

I am also more and more leaning that way, also because I could add a extra manual gearbox part, so that the motorized switching engages one of 2 functions that are then selected manually, because the 3 remaining  gearbox outputs aren't enough for 5 function

 

[crazy technic]

here's another update, the gearbox is done, it consists of 2 parts: a motorized selected part, and manual part, the motorized selector selects option 4 and then you have to chose between 2 other functions, 

this was the only option to get 5 functions + a gearbox in this small space. and you will rarely have to switch between the 2  manual functions as one of them is hardly used (and optional in the real excavator)

I also managed to build the dozer blade on the front, that will also be a manual function, because it wouldn't be possible to add more functions to the gearbox.