[TC22] Backhoe grader - inspired by Hydrema 614

[MP LEGO Technic creations]

Hello everyone!

For this contest I've decided to build a compact backhoe grader inspired by this one:

List of planned functions:

1) Articulated steering with a working steering wheel

2) Pendular rear suspension

3) Worm-gear-operated front bucket lifting

4) Pneumatically tilted front bucket - via 2 small pneumatic cylinders, linkage holds the bucket in the same position during lifting

5) Pneumatic rear support legs - via 2 thick short cylinders

6) Rotating rear arm - 2 small pneumatic cylinders

7) 3 small pneumatic cylinders on the rear arm

I know that it might seem to be too much but I'll try to do my best when implementing those - the toughest problem is of course going to be space, so I decided to make the cabin smaller than the original has.

Now about what's already been done:

Articulated steering is provided by a small turntable, axle for the steering wheel has also been placed.

Pendular rear suspension works already too (2 rubber 2x1 liftarms) but because of the lack of any stoppers, it can collide with the rear outriggers' support easily

Front arm and the linkage are fully working, altouhg it's not connected to any sort of mump neither a switch, as well as the support legs and the rotating base of the rear arm.

 

Now a few pictures from the building process:

 

 

 

 

 

 

 

 

Thank you all for visiting & comments are welcome!

Edited April 10, 2022 by MP LEGO Technic creations
a typo

[1gor]

Very cool choice. I see lots of interesting projects in this TC and your is one of them. I really like that you decide to make it with smallest tractor tires

[trekman]

This is a really nice build, and the smaller tyres work so well. I will be watching this one.

[Jurss]

Already impressive. 

Havne't seen this kind of thing in real. Yes, something similar, but not exactly that compact type.

[Jundis]

Incredible start already, the rear part is so compact yet so functional and looks great, too!

I guess a pneumatic lifting of the front bucket couldn't be done due to scale limitation and the interfering mechanics of the bucket tilt?

[MP LEGO Technic creations]

Thanks @1gor, @trekman and @Jurss, I'm glad you like it!

@Jundis, you're right. Pneumatic lifting would've need 2 more cylinders and it was not easy to place pneumatic hoses even for the tilting ones. (So cylinders would fit, hoses probably would't). Anyway, I'm pleased you like it already.

[Paul B Technic]

Well done, a great start.

[Maaboo the Witch]

I was thinking of doing one of these the other day. Perhaps not for the contest though. I had the Wolf Wz45-17 in mind.

[SaperPL]

Really good start. I like how the supports are made without nedlessly wasting space to make supports that go sideways. This approach is good too.

Right now the wheel distance feels a bit off without picturing this specific excavator, but looking at the pictures I guess you've measured that correctly and it will be as in the real life vehicle when you'll put the cab on top.

[MP LEGO Technic creations]

A quick progress here.

I made someting that could be called "a cabin", although from some reason I'm not very satisfied with some parts of it.

All pneumatic switches (6) have been placed inside, I also decided to change the colour of the fenders from black do DBG, as I think it looks better.

Apart from that, I've slightly changed the design of front and rear lights and made the connection between the bodywork and support legs stronger.

 

 

[Jurss]

Cabin is already really good.

[mpj]

Very clean, it almost doesn't look a technic set!

[Akassin]

Such a clean design! Incredible!

[MP LEGO Technic creations]

3 hours ago, Jurss said:

Cabin is already really good.

Thank you!

16 minutes ago, mpj said:

Very clean, it almost doesn't look a technic set!

 

2 minutes ago, Akassin said:

Such a clean design! Incredible!

I'm glad you think so!

Anyway there's something I haven't thought about before - the pump placement, there just doesn't seem to be the right one... 

[1gor]

2 hours ago, MP LEGO Technic creations said:

 

Anyway there's something I haven't thought about before - the pump placement, there just doesn't seem to be the right one... 

There are also small pumps (like used in Unimog and Arocs)...

[MP LEGO Technic creations]

1 hour ago, 1gor said:

There are also small pumps (like used in Unimog and Arocs)...

I know that, I even have a few of them, but still don't know where to place it. Anyway, something will definitely come to my mind...

[Thirdwigg]

Great job, and it keeps getting better with each update. The cabin looks great!

I'm interested in the next update with the rear boom.

[jorgeopesi]

I am very impressive with this entry great work.

[Jundis]

I'll so gonna steal your solution of the back shovel attachment :D

[MP LEGO Technic creations]

14 hours ago, Thirdwigg said:

Great job, and it keeps getting better with each update. The cabin looks great!

 

12 hours ago, jorgeopesi said:

I am very impressive with this entry great work.

Thank you! 

 

9 minutes ago, Jundis said:

I'll so gonna steal your solution of the back shovel attachment :D

I believe I've just got an idea how to reinforce it 

[SaperPL]

The cab is awesome, but how about the no-model team approach? Aren't the rounded areas in front of the cab, edges of the roof and grey edges over rear wheels exactly what you would call a model team approach?

I'm asking because I'm wondering where is the boundary when it comes to model team approach and I'll have to use some system bricks in few places because I'll have micro motors and studded hub.

Or does the model team approach is supposed to be treated as a whole model/outside of it with system bricks and not only just parts of it?

[MP LEGO Technic creations]

23 minutes ago, SaperPL said:

how about the no-model team approach? Aren't the rounded areas in front of the cab, edges of the roof and grey edges over rear wheels exactly what you would call a model team approach

I wouldn't call it like that... jokes aside, I got your point. Anyway there is no other easy way to make the cabin as rounded as it is now without using system peices.

 

23 minutes ago, SaperPL said:

Or does the model team approach is supposed to be treated as a whole model/outside of it with system bricks and not only just parts of it

This is how I understand it either.

 

23 minutes ago, SaperPL said:

I'm asking because I'm wondering where is the boundary when it comes to model team approach and I'll have to use some system bricks in few places because I'll have micro motors and studded hub

I can't see an exact border between those, maybe ask @Jim for clarification? If I built it in a wrong way, I'll of course make it right, although the result won't be as nice (at least for me).

Because micro motors only have studs on them, there's just no other possibility than mounting those on some studs, so IMO that's alright.

Edited April 14, 2022 by MP LEGO Technic creations

[SaperPL]

Yeah, that's my point, I'm not sure whether I should be paranoid here and avoid using system elements in bigger visual accents, and whether I can get away with making a big portion of the cab with system bricks because there's a system/brick shaped hub on the inside. Let's see what @Jim says about it. If that's okay as long as we're not going full system on the outside, then maybe I should make a system based cab to have half stud gap between it and the arms of my loader

[MP LEGO Technic creations]

First of all, I've switched to Hydrema 614 backhoe grader:

I also had to omit some of the planned functions - pendular suspension and working steering wheel in exchange to some other, more unusual ones.

Pneumatic functions are going to be operated by a large pump instead of the exhaust pipe (black one from 8455 is on the way with some DBG parts for the cabin...)

Here's the current state (I'm sorry for all the hoses sticking out from the cabin - all of them are going to be hidden inside): 

 

As far as I know, the range of the movement is similar to the real machine.

Gear in the center - articulated steering

Gear in the left - outriggers

Gear in the right - rotating the cabin (oops, please read till the end to know more )

There was no way how to keep the outriggers pneumatic - sorry to all of you, who liked those.

I quickly grabbed some Power Puller tyres to demonstrate underground digging.

Swinging rear arm - operated via tan bevel gear behind the cabin connected to a worm gear and small turntable.

 

 

Rotating rear bucket.

At this point, here's a special feature of this digger - almost 360° rotating cabin.

 

And here are the possibilities provided by this trick - 13x34x22.5=9945 cubic studs

Thank you for visiting & comments are welcome as always!

[1gor]

Impressive amount of features in such small package