[MOC] Trial Truck 6x6 [free building instructions]

[keymaker]

Hi,

I hesitated if I even should post this MOC here since it is so simple but at the end here I am. I created this truck mostly to have some fun outdoors. It has minimal amount of features and its main goal is to drive over not so pleasant terrain, like sand, mud, snow and even quite deep water. And I can do that without fears, that drivetrain will jamm, gears will skip, motors will get wet and at the end I won't have desire to clean all this mess up.

I also very like the closing mechanism of "differentials" covers. It is simple, effective, works like a charm and has satisfying click when closing.

This Truck is also testing ground for a couple of solutions I wanted to try out, like drive shafts connected to the axles at the angle, steering controlled by rod or way of suspension for both front and rear axles.

 

Nevertheless please enjoy the video, use the instruction and check some details below if you want to know more.

Instructions: https://rebrickable.com/mocs/MOC-136120/keymaker/trial-truck-6x6-rc/#details

Some details and main functions:

• dimensions LxWxH: 37,5x13x15cm
• weight: 1132g
• 6x6 drive (3xPF L motors)
• steering (PF servo)
• suspension on all axles
• completely secure bottom of the truck with panels
• easy access to all "differentials" via openable covers

Couple of highlights why this truck can be fun to build and to play with:

• Drivetrain - it is very solid, so you won't hear skipping gears, if wheels aren't spinning, then you either broke some part or stalled motors. It is also super easy to use different gear ratio or different number (1/2/3), type (M/L/XL) or even technology of motors (PF/C+). What is more, removing all electronics takes only couple of minutes and truck is ready to taking the shower to clean all evidence of you off-road madness
• Construction - it is very rigid and solid, you can lift it up by almost any part of the frame and body
• Off-Road Design - all gears are protected so you don't have to be afraid that they will jamm due to sand, mud, snow, stones etc. And even if something get inside "differentials", it is super easy to open covers and clean this up. Last but definitely not the least - ability to drive through deep water - UP TO 8CM! It over half of the height of the truck. 8cm of water and your electronics is still safe.

Internals of the truck:

P.S. I know it is rather ugly, but it brings fun! :)

Edited January 28, 2023 by keymaker

[Zerobricks]

What a brillinat idea using these L panels to simply click into place!

And I agree, protection from dirt is very important when offroading, a simple stray piece of rock or grass can wreak havoc on your driveline, damaging and disabling your model.

If I see correctly, the drive goes to the rear axles at an angle? Got more pictures of it? And the rear axles are atatched using only one bottom link + a panhard rod? I asuume there's a top link somewhere too.

Well done, really compact, though I would recommend using the small CV joints instead if U joints, since there's no 3L stud axle to slip out (I assume you used 5,5 in the video cause of this issue?).

[keymaker]

5 minutes ago, Zerobricks said:

If I see correctly, the drive goes to the rear axles at an angle? Got more pictures of it? And the rear axles are atatched using only one bottom link + a panhard rod? I asuume there's a top link somewhere too.

Each axle has own drive shaft connected directly to axle for maximum efficiency. And all of them are connected to axles at an angle for better GC and ramp angle. Rear axles are connected via upper common links and single bottom links. The last axle also has a panhard rod. I need to to prepare render of internals, then it will be better visible.

10 minutes ago, Zerobricks said:

Well done, really compact, though I would recommend using the small CV joints instead if U joints, since there's no 3L stud axle to slip out (I assume you used 5,5 in the video cause of this issue?).

I decided to use cardans and 5,5 stud axle to have better angle and to be sure, that no matter what, I do not lose the wheel even in rough terrain. It doesn't look good, but when you play outside, it doesn't really matter. And you can always use 3 studs axles for better look (I did it for photos and indoor part of the video)

[gyenesvi]

Well I would not say it’s that simple :) It’s got some pretty unique and interesting solutions. Nice suspension, innovative drivetrain, and I love that steering system, it’s a great idea to combine a steering rack with a linkage based solution, though I have yet to understand how the steering rack interferes with the chassis construction (I often have the problem that the chassis is in the way for linkage based steering). All of that in a small scale package, and I’d even say it looks cool. The simplicity of the paneling and the right shapes is what makes it look good. Great design altogether! Thanks for sharing!

One question, at the front axle, does that assembly fit all the way into that wheel hub? That way is the steering pivot reasonably close to the wheel even with a U-joint?

[keymaker]

21 minutes ago, gyenesvi said:

One question, at the front axle, does that assembly fit all the way into that wheel hub? That way is the steering pivot reasonably close to the wheel even with a U-joint?

Yes, that is why I love those new small rims. This one stud deeper connecting point does the job.

Edited January 27, 2023 by keymaker

[jorgeopesi]

Nice one and great ideas  .

[Celeri]

Great trial truck, so much better than the Zetros!

It looks nice and its performance seems very enjoyable, bravo!

Edited January 27, 2023 by Celeri

[LEGO Train 12 Volts]

Nice truck and wonderful video!

I love the trial in the snow!

[nerdsforprez]

14 hours ago, Zerobricks said:

What a brillinat idea using these L panels to simply click into place!

And I agree, protection from dirt is very important when offroading, a simple stray piece of rock or grass can wreak havoc on your driveline, damaging and disabling your model.

Not to mention it avoids parts of the underside getting snagged on things like rocks, twigs, or whatever you are crawling over.   Terrific idea.  So glad you chose to share this build.  

Edited January 28, 2023 by nerdsforprez

[Aleh]

Hey! Fascinating climbing abilities! The cab looks a bit boxe to me, but this is a personal taste :)

[williamyzfr1]

Two questions from someone who owns the Zetros and a 2007 PF IR remote controlled bulldozer.

1. Why is the PF Servo so expensive to purchase?

2. How do you control this fantastic creation - I couldn't see any PF IR modules installed?

Edited January 28, 2023 by williamyzfr1

[keymaker]

1 hour ago, williamyzfr1 said:

Why is the PF Servo so expensive to purchase?

Because PF servo motor was present only in 3 sets where one of them was in limited edition. And all of them are around ten years old.

1 hour ago, williamyzfr1 said:

How do you control this fantastic creation - I couldn't see any PF IR modules installed?

Buwizz 2.0 behind the cabin. But you can use any hardware you want, to drive, steering and controlling the truck. It is easy as it gets in this truck

Edited January 28, 2023 by keymaker

[williamyzfr1]

24 minutes ago, keymaker said:

Because PF servo motor was present only in 3 sets where one of them was in limited edition. And all of them are around ten years old.

Buwizz 2.0 behind the cabin. But you can use any hardware you want, to drive, steering and controlling the truck. It is easy as it gets in this truck

Thank you, unfortunately Buwizz exposeses another gap in my knowledge but I guess we are all on a learning curve.

Would I need a genuine servo or is there a Buwizz equivalent?

 

Edited January 28, 2023 by williamyzfr1

[keymaker]

22 minutes ago, williamyzfr1 said:

Would I need a genuine servo or is there a Buwizz equivalent?

Buwizz is a 3rd party equipment, it serves for power and remote control. But to steer the truck you need PF servo or C+ L motor or whatever Lego motor you have and know how to use for the purpose of steering.

Edited January 28, 2023 by keymaker

[Lego Tom]

Simple yet impressive! Any plans to add steering to the rear axles?

[keymaker]

7 hours ago, Lego Tom said:

Simple yet impressive! Any plans to add steering to the rear axles?

Thank you and other people for kind words :) I do not have plans to add steering to the rear axle.

 

And the rules deciding which MOC will be featured on main site and which doesn't are completely beyond my understanding, but quoting famous Palpatine sentence: "A surprise, to be sure, but a welcome one" :D

[Jurss]

Missed somehow this until today. 

Really good trial truck, and that cabin fits very well to it.

[Mechbuilds]

high quality work as usual! Well done! 

[Corrado]

I love the robustness, especially the gear covers. What about stability with such a high center of mass?

[keymaker]

39 minutes ago, Corrado said:

I love the robustness, especially the gear covers. What about stability with such a high center of mass?

Thank you. I haven't test it on slopes, since the main goal was to be able to withstand mud, sand and quite deep water.