[MOC] Kalmar DCG180-330 Heavy Forklift

[JLiu15]

Model of a Kalmar heavy forklift controlled using SBrick. Features drive, steering, fork elevation, pneumatic mast tilt, kissing forks, tilting cab, 6-cylinder engine, and lights.

Functions/features:

• Drive
• Steering
• Fork elevation
• Mast tilt (pneumatic)
• Kissing forks (manual)
• Tilting cab
• 6-cylinder engine
• Lights

It's been a while since I created a MOC featuring pneumatics, and even longer since I created one with remote-controlled pneumatics. My last MOC with fully remote-controlled pneumatics was from 2015, and that was before I had an SBrick. Ever since I obtained an SBrick I had made two MOCs with remote-controlled pneumatics - a front loader in 2016 and a Volvo EC350E excavator in 2019. However, both projects were cancelled before I finished them. I realized the mast tilting function on a forklift would be a good choice for pneumatics, especially the 7L cylinders. I originally just wanted to make a generic heavy forklift, but when I came across Kalmar's heavy forklifts I was really intrigued by their design so I decided to make the DCG180-330 by Kalmar.

My model maximizes functionality while minimizing the amount of moving parts. Most functions have their motors connected directly to their inputs, thus minimizing moving parts and optimizing chassis space. The drive motor is placed directly behind the differential, and gear reduction is done via portal hubs placed horizontally. The servo motor for steering is placed vertically in the chassis, connected directly to the steering linkage without a rack-and-pinion mechanism. This allowed for a large steering lock which is commonplace among forklifts, but this also meant that the chassis around the axle has to be thin so the wheels don't bump into them - in fact, the chassis is only 3 studs wide in the rear but is reinforced well nevertheless. I limited the servo's range of movement in the SBrick profile designer as the steering input can only turn about 45 degrees each way. Even then I still had to add towballs as limiters to the steering mechanism to ensure the wheels don't rub against the rear body panel when turning. In the end, I wish the wheels could steer a little tighter, but the end result is impressive nonetheless.

The mast is built with a PF L motor near the top, which drives a worm gear mechanism controlling fork elevation. The section that lifts up is essentially a frame with two sets of racks that contain the fork module sliding freely within it. A single rope pulls the fork up, and the range of movement is pretty impressive. The fork module contains two manually controlled linear actuators that allow the forks to move closer to each other - "kissing forks", as the PDF for the real-life counterpart calls it. The pneumatic system for the mast tilt function is comprised of a PF L motor driving the compressor and a PF M motor controlling the valve. The L motor for the compressor is geared up slightly to allow rapid pumping, and the valve mechanism is placed at the very front of the model to minimize the length of the hoses connecting the valve to the cylinders.

Other features include a tilting cab, a 6-cylinder engine with mini pistons below the cab, and lights connected directly to the 8878 battery so the speed dial on it can be used to control their brightness. The 6-cylinder engine is accurate, as one of the engine options on the real Kalmar DCG180-330 is a Cummins B6.7. The fake engine is connected directly to the drivetrain and makes a pretty cool noise while driving. The functions overall worked pretty well - it had decent driving speed, a really good turning radius, the fork elevation had sufficient torque without being painfully slow and the pneumatic mast tilt had good precision. There were some issues - such as the fork elevation mechanism skipping at the racks when under load and the pneumatics not being able to tilt the mast back when the fork is fully raised and the mast is fully tilted in the forward direction. The fork mechanism also lacked a clutch, so it was really important to stop the motor precisely at the moment the fork reaches the bottom to prevent it from stalling. Still, given how well the functions worked overall and how realistic and detailed the bodywork is, I feel like this MOC was a great success.

Video:

Photos:

 

 

 

 

 

 

 

Edited July 12, 2020 by JLiu15

[Mechbuilds]

i'm the guy who commented on your video "it turned out amazing" it really did. Looks stunning! So many features packed in. I love it that you could squeeze in the cabin tilt feature so the motor can be seen. 
It was a good decision to move the boom lift further back.  

[Pattspatt]

Fantastic job! Love how functional it is - it looks like everything works at a nice speed, too. Any chance of a close-up of your servo motor steering connection?

[JLiu15]

3 hours ago, Mechbuilds said:

i'm the guy who commented on your video "it turned out amazing" it really did. Looks stunning! So many features packed in. I love it that you could squeeze in the cabin tilt feature so the motor can be seen. 
It was a good decision to move the boom lift further back.  

Oh haha I saw that 

But yeah, I'm glad you like it, and once again thanks for your support in the WIP topic 

Here's a secret - the fake engine wasn't actually part of the original plan. I only added it when I found sufficient space for one, and this was thanks to keeping all the motors close to their respective functions thus optimizing space in the chassis.

1 hour ago, Pattspatt said:

Fantastic job! Love how functional it is - it looks like everything works at a nice speed, too. Any chance of a close-up of your servo motor steering connection?

Thanks! And yeah one of the things I like about how this MOC turned out is how all the functions work with a pretty good speed - like nothing is painfully slow.

As for the steering, you can take a look at my WIP topic to get a general idea of how it's done. The first few images should have a pretty good view of it.

 

[qwest70]

This is great MOC. Where I can see how implemented pneumatic engines or examples same models, where are these engines  ?

[Mechbuilds]

Whats the maximum lift capacity? How much can it lift? 

[suffocation]

What a beauty

The functions are flawless and the overall look is so sleek & clean.

[Mr Jos]

Very nice MOC.

Size, speed, turn radius etc all look good. Only thing I seem to notice is that the mast tilt seems to not stay stable when you drive around with a load. Looks like it starts to tip over.

Well done!

[JLiu15]

7 hours ago, qwest70 said:

This is great MOC. Where I can see how implemented pneumatic engines or examples same models, where are these engines  ?

Thanks! You can take a look at some recent Technic sets featuring pneumatics for a general idea of how they're implemented, such as the 42043 set. You can get individual pneumatic elements here:

https://www.bricklink.com/catalogList.asp?catType=P&catString=159

6 hours ago, Mechbuilds said:

Whats the maximum lift capacity? How much can it lift? 

The L motor has plenty of torque so it has a pretty good lift capacity in theory, but unfortunately the mechanism starts skipping under load. I'm guessing a little more reinforcement where the pinion gears meet the racks would've solved that.

4 hours ago, suffocation said:

What a beauty

The functions are flawless and the overall look is so sleek & clean.

Thanks! I'm glad you like it 

[JLiu15]

21 minutes ago, Mr Jos said:

Very nice MOC.

Size, speed, turn radius etc all look good. Only thing I seem to notice is that the mast tilt seems to not stay stable when you drive around with a load. Looks like it starts to tip over.

Well done!

Thanks!

As for the mast tilt, I agree - a drawback of pneumatics is that they can't hold the load precisely in place like linear actuators can. Nevertheless, the pneumatics worked a lot better than I expected here. I was worried they won't have enough load capacity to tilt the mast, but they can tilt it back just fine even with the fork completely raised.

[LEGO Train 12 Volts]

Beautiful forklift ... in the video the perspective gave the impression that the model was real!

[JLiu15]

6 hours ago, LEGO Train 12 Volts said:

Beautiful forklift ... in the video the perspective gave the impression that the model was real!

Thanks! Yeah the model turned out pretty realistic in the end imo, probably one of my most realistic MOCs up to date.

Edited July 14, 2020 by JLiu15

[Thirdwigg]

Great job, this Kalmar turned out great. The cab turned out perfect, and the rear sides over the wheels look great.

[JLiu15]

8 hours ago, Thirdwigg said:

Great job, this Kalmar turned out great. The cab turned out perfect, and the rear sides over the wheels look great.

Thank you! 

[HUWI]

You asked for pics, here they are...

The weight of the bulk container is 1.1kg and the YT video is the evidence that it can lift it.

At a small meeting last week it could not lift the bulk because of the gears in the bottom of the mast.

Greetz from Germany,

Chris

Edited July 18, 2020 by HUWI

[siriuspaul]

The appearance  looks great! Maybe penumatic system is not so convinent to control and doesn't have enough capacity .

[JLiu15]

13 hours ago, HUWI said:

You asked for pics, here they are...

The weight of the bulk container is 1.1kg and the YT video is the evidence that it can lift it.

At a small meeting last week it could not lift the bulk because of the gears in the bottom of the mast.

Greetz from Germany,

Chris

The pics aren't showing up...

EDIT: nvm I saw your video of it.

12 hours ago, siriuspaul said:

The appearance  looks great! Maybe penumatic system is not so convinent to control and doesn't have enough capacity .

Yeah that's one of their drawbacks, but they are fun to use though 

Edited July 18, 2020 by JLiu15

[HUWI]

They aren't showing up? That's suspect, i can see them in my post aund in your reply... EDIT: now i found the Problem, you have to be logged in at the doctor-brick forum, i have to link other platforms.

You can see also them in Nico's fan gallery: https://rebrickable.com/mocs/MOC-27807/Nico71/42082-model-d-heavy-forklift-truck/#photos

 

Edited July 18, 2020 by HUWI

[JLiu15]

4 hours ago, HUWI said:

They aren't showing up? That's suspect, i can see them in my post aund in your reply... EDIT: now i found the Problem, you have to be logged in at the doctor-brick forum, i have to link other platforms.

I can see your other pics now.

I love how it looks like Nico71's forklift on the outside but the inside is totally different, with Control+ motors and all that instead of the distribution gearbox 

Edited July 18, 2020 by JLiu15

[HUWI]

Just now, JLiu15 said:

I can see your other pics now.

I love how it looks like Nico71's forklift on the outside but the inside is totally different, with Control+ motors and all that instead of the distribution gearbox 

Yes,  i changed all my links. Pictures in this forum have to be smaler than in our small forum.

 

Thanks, i gave my very best. Because it isn't a D-Model i could ad some details like air filter and steps. I build the axles and i knew the wheelbase, so it was easy.

 

The only fault is, that the tires are too small. The scale is round about 1:17, but the tyres are round about 1:20

and for the right scale i would have to redisign everything. Also i don't know such big wheel with street profile, only military.

[JLiu15]

17 minutes ago, HUWI said:

The only fault is, that the tires are too small. The scale is round about 1:17, but the tyres are round about 1:20

and for the right scale i would have to redisign everything. Also i don't know such big wheel with street profile, only military.

Honestly they look perfect - I used them on mine too. Also Nico71 used them on his forklift as well.

It's just one of the limitations of Lego ig...the next size up I can think of for these rims is the tractor tires from the CLAAS set, which really aren't well-suited for forklifts (unless you're talking about an off-road forklift, ofc )

[HUWI]

these tyres with a diameter of 106mm would be an option, they fit on the LEGO rim: https://store.rc4wd.com/MIL-SPEC-ZXL-19-Tires_p_1957.html

but i think my calculation was something about 120mm. The real DCG 620 is much bigger than yours...

9 minutes ago, JLiu15 said:

It's just one of the limitations of Lego

That's it...