[MOC] Large Excavator

[LennyRhys]

Hey folks, it's been a while.  You may know that I'm pretty fond of construction vehicles, and I've been building minifig scale excavators for 30+ years now.  I feel that the part selection has finally reached a point where very realistic-looking machines can be made in minifig scale.

In saying that, I made two new parts for this build:  the pistons, which are 9L axles inside tubes, and a 1/2 bush at the end for friction; and a bucket.  I'm still waiting for TLG to make better excavator buckets for their models, and while they won't make buckets, I will!  The original bucket from 8851 is actually a good size for this model, but the lack of teeth and the dated styling make it look pretty bad IMO.

So yes, it is possible to build this model entirely from official Lego parts, but with these additions it looks so much better.  I'll get around to sharing more photos soon and I'm also working on instructions, which will take quite a long time.  I might even put up a video because it's really nice to have a model of this size that is completely posable.  Thanks for looking!

Edit: I've added more photos of the model showing the features, including the detachable counterweight at the back which reveals the engine bay; access to the hydraulic pumps beside the engine; access into the engine house where the soft lines are; and access to the air filters and radiator on the other side of the machine.  I've used some old pneumatic hose that I've kept for decades, and also the flexible hoses from older city models.

More pics showing some of the features built into the model.

 

 

 

Edited September 22, 2020 by LennyRhys

[JintaiZ]

Fantastic build! I like the custom box you made for it. 

Edited February 5, 2021 by JintaiZ

[LennyRhys]

Thanks JintaiZ!  I've updated the OP with more photos that I took yesterday evening.  Still waiting on a couple of parts to arrive in the correct colour, but I'll make a short video soon.

[DodgeDude5498]

Absolutely incredible build! Love the motor details!

[LEGO Train 12 Volts]

What a beautiful machine! 

[jpx]

Very very cool MOC! 

Did you 3D-print the excavator bucket? Anyways, it looks fantastic! 

[Metagross555]

So dang good, only thing I have to critique, is that the arrow on the track frame is pointing the wrong way, the drive motor hubs are opposite the forward driving direction.

[DanOfBricks]

This looks incredible! I most definitely would buy this if it were an actual LEGO set! Do you have any MOC's of a Front Loader Backhoe for a City scale?

[LennyRhys]

Thank you very much for the kind comments folks.    @DanOfBricks, yep I've also done many backhoes over the years, and shared one here a while back:

 

I've been working on the model some more, as I thought it might be nice as part of a larger set.  I put together a prototype haulage truck and multi-axle trailer specifically for this heavy load.  If it were up to me, TLG would release more models like this which are for the advanced builder, but not Technic.

First, here's what the excavator looks like with the 8851 bucket and without the cylinders.  It's OK I guess, but not as good with the custom parts - for starters, I can't pose it!

Here it is on the trailer.  There's no way a standard plate-style City trailer would take the weight of the excavator, so I made it with the dolleys and beams.  Lego is always going to bend a little bit, but it takes the excavator's weight no problem.

And the prototype tractor unit (I used some of my son's Lego for this...!)

Finally, a shot of the bucket for @jpx  - it's made from sheet styrene, cut with a craft knife.  I did my best to mix up acrylic paint in DBG and brushed on a couple of coats after priming in red.

 

[Pisces no Aphrodite]

Better than LEGO.

[Toastie]

On 9/26/2020 at 6:13 PM, LennyRhys said:

it's made from sheet styrene, cut with a craft knife. 

As @Ragana9289 said: Better than LEGO (can do). Not only the bucket. The entire model (MOC is not really capturing it: It is a "Model", in many regards!).

30 years of experience very, very clearly show - everywhere.

3D printing - even using more expensive devices - would not even come close to the finish of your hand-crafted beauty. Do you do rail-road (or the like) "modeling" by any chance? Whenever I see what these folks accomplish with sheets of styrene cut and glued to perfection, bridges, houses, any "structures": I am blown away. First it is white or whatever color, then an initial coat of something, then several coats of something else. In the end, it looks like a perfect injection molded piece.

As your bucket does.

This model is truly representing the art of building as well as the art of creating custom parts.

Congratulations!

All the best
Thorsten

Edited September 27, 2020 by Toastie

[LennyRhys]

Toastie, thank you so much for your kind words.  I find Lego a great creative medium and it's nice to be able to make custom parts that I used to imagine when I was younger.  I always used the helicopter window (2483) as an excavator bucket... it's actually the perfect shape but has no sides.  Now that I can build buckets myself it's nice to see how they look on custom Lego models.

I've been doing scale model making for some years now, which is where I learned to work with styrene.  It comes in really handy when prototyping Lego parts!

[koalayummies]

Absolutely wonderful and hyper-realistic creation. The detail and authenticity in your design makes this one of the best minifigure scale construction vehicles ever. Love it, fantastic work.

[zweifuss]

Beautiful work! Just curious why you chose the older technic 3873 https://www.bricklink.com/v2/catalog/catalogitem.page?P=3873 treads over the newer 57818 https://www.bricklink.com/v2/catalog/catalogitem.page?P=57518 ones? I love the design of the new treads, it's a very cool piece. Also impressive you made the bucket not as a 3D print, that's some talent right there.

[bricksboy]

It is excellent! Thanks for sharing :D

[supertruper1988]

16 hours ago, zweifuss said:

Beautiful work! Just curious why you chose the older technic 3873 https://www.bricklink.com/v2/catalog/catalogitem.page?P=3873 treads over the newer 57818 https://www.bricklink.com/v2/catalog/catalogitem.page?P=57518 ones? I love the design of the new treads, it's a very cool piece. Also impressive you made the bucket not as a 3D print, that's some talent right there.

@LennyRhys can probably answer more clearly but I know as a model maker myself, the tracks are likely used because they match the real thing or as close as LEGO makes. The larger, newer, tracks would look to big on this model IMO. 

[snaillad]

A very realistic and polished build, great work!

[Marcoe14]

Huge machine, nice details. Seems to me better than many official sets. Very smooth.

[LennyRhys]

Thank you so much for the lovely comments everyone.   As supertruper1988 said, the new Technic tracks would be much too big even for a very large minifig scale excavator.  Real excavators have quite narrow tracks, especially if they work in hard rock environments.

I'll see if I can put a small video together this weekend.  I'm also slowly working on the instructions using Ldraw, which is new for me, but I'm getting there!

[LennyRhys]

I worked a little more on the instructions this evening.  The counterweight is done and I've been doing some tweaking to the internals of the machine before I finalise it for the LDCad file.  I think I'll have to use photos for much of it because the hoses will be too complex for the digital file (unless I import it into Maya or something).  Here's a quick pic of the internals as they are at the moment - there's a lot going on in a little space!

[arealhuman]

I adore those greebles.

[bramn]

Awesome build ? I am very much looking forward to the instructions! My brother-in-law has a demolition company and I would love to give him a cool MOC as a birthday present one day ?

[LennyRhys]

Thank you arealhuman and bramn!

Just out of curiosity - what is people's choice of Lego CAD software?  I used MLcad previously and it was very easy and also powerful enough to create quite complex models.  I'm currently using LDcad and I just can't seem to get into the groove... it's not very intuitive and there are simple functionalities that I can't seem to find (like importing one completed model into another file).  It's nice having the steps for instructions, but how on earth the submodel setup works is beyond me!

[Toastie]

16 minutes ago, LennyRhys said:

I used MLcad previously and it was very easy and also powerful enough to create quite complex models. 

I am fully with you here - never change a running system. I still do use MLCad as there was no reason to make a transition to other software.

However, I believe this is really just a matter of getting used to it or what you grew up with. Learning the tricks and tweaks of new software is inherently difficult without to the detail manuals, which is in turn a pain in the butt to make.

But again: MLCad works for me and works - as far as I can tell - flawlessly.

Best
Thorsten

 

[zweifuss]

On 9/30/2020 at 5:33 PM, LennyRhys said:

Thank you so much for the lovely comments everyone.   As supertruper1988 said, the new Technic tracks would be much too big even for a very large minifig scale excavator.  Real excavators have quite narrow tracks, especially if they work in hard rock environments.

I'll see if I can put a small video together this weekend.  I'm also slowly working on the instructions using Ldraw, which is new for me, but I'm getting there!

OK cool makes sense. I love the details in the engine compartment, I think you're right that CAD would choke on it, whether it be LDCAD/MLCAD or LDD. I find any flexible system in Lego designer CAD is always just a bit wonky. The software the internal team at LEGO uses must not have these kind of issues.