[MOC] Off-road truck KrAZ 255 v2.0 (SnowRunner Ep2) [instructions available]

[keymaker]

Hi,

 

I present my newest creation – off-road truck KrAZ 255 version 2.0. This is successor of my first public MOC – KrAZ 255 to which free instruction are available here. The goal in version 2.0 was to improve basically every aspect of predecessor and to pay respect to this awesome off-road truck. And as usual, most of the features are based on truck Tayga 6455B available in game Snowrunner. This truck is also the next part of my Snowrunner series started with Chevrolet CK1500. On the video below you can check what details and functions I was able to put into this MOC and how KrAZ 255 v2.0 deals with off-road terrain and against obstacles. Extensive list of features, details and interesting facts about this creation you can find below the video. Enjoy!

 

Instructions: LINK

 

General details:

• scale: 1:23
• dimensions LxWxH: 42,5x13x16,5cm
• weight: 1525g

 

Features:

1. RC front axle steering (C+ L motor)

• positive caster (click)
• Ackermann geometry
• almost perfect pivot point (click)
• PF servo friendly - 180 degrees of movement for steering input

2. RC 6x6 drive (2 x C+ L motor)

• independent drive input for each front wheel (click) (for this idea I would like to thank @Fluwoeb and this topic, this is because of you! )
• rear wheels driven by two independent inputs (one for 2 left wheels and one for 2 right wheels) (click)
• front wheels driven by one differential and rear wheels driven by second differential (click)
• both differentials coupled together to harness power of two C+ L motors
• both differentials coupled with lock mechanisms (click), controlled separately and manually from the cabin (click) and equipped with visual color indicator of diff lock on/off status located behind the cabin (click)
• power train equipped with new big CV joints - cardans and old CV joints limited in drive of the front axle and completely removed from drive of rear axles

3. RC winch with place to lock the hook (C+ L motor)

4. RC front and rear lights (Lego LEDs)

5. suspension for all 6 wheels (click)

• front wheels on live axle suspension with shock absorbers (click) and a big range of movement (click)
• rear wheels located on independently oscillating arms with rubber suppressors controlling the movement (click)
• rear suspension without shock absorbers - no side leaning and no bending under the load (click)

6. three studs ground clearance (click)

7. bottom of the truck armored with panels to secure crucial mechanisms and improve dealing with obstacles (click, click)

8. two hooks for connecting trailers, front and rear one, both equipped with lock/unlock mechanisms

9. openable doors, hood, tool box, first aid kit, sideboard bed with separately openable sides, each one with two locks

10. working V8 engine with fan which can be easily removed “for maintenance, repairment or for swap” located in detailed engine bay with a grill via which working engine can be watched (click)

11. detailed two seats cabin with openable and usable glove box (click)

12. working steering wheel

13. modular construction (axles, cabin, additions can be easily disconnected)

14. powered by Buwizz 3.0 but also prepared to be powered by standard C+ Hub (click)

15. prepared to be built also with PF motors and PF servo without significant changes and to be powered by Buwizz 2.0 (click) or even standard PF Battery box with IR receivers (click)

16. "disk brakes" in front (click) and rear wheels and many others small details (click, click, click)

17. equipped with many additions from the game Snowrunner, like bull guard, exterior roll cage, roof rack with fuel canisters and spare tire, double snorkel, sun protector (click)

 

 

Interesting facts, designing decisions and details:

• driveshafts for front axle are connected in a way that the longer, more “smooth” CV joint part are connected closer to front axle, so lower to the ground, which corresponds with the idea to prepare bottom of the frame smooth and resistance to sticking out objects which can immobilize the truck (click)
• most of the motors are placed symmetrically at the center of the truck, which is good for weight distribution, but Buwizz unit is localized off centered, closer to the left side of vehicle. To balance that, motor from winch is placed also off centered, but closer to the right side of truck (click)
• all wheels can harness power from both C+ L motors, as they are coupled, but rear axles, which in general generate more load for motor, are connected closer to the right motor, that is why V8 engine is connected closer to the left motor, which is connected closer to front axle, as the front axle generates less load than rear ones (click)
• additionally output for V8 engine has the same speed as motor output - which is higher than rest of the drivetrain - for better visual and sound effect (click)
• there is a „biscuit connector” placed in rear wall of the cabin to increase ways of location and connection and types of power source which can be used to power up the truck (click)
• to avoid widening the whole truck, only hinges for sides of sideboard bed are located outside of the sideboard bed to allow opening sides to vertical position, which makes loading the cargo easier (click)
• positive caster present in front axle has (apart from being next feature adapted from real cars, apart from dealing with not very high tolerance of Lego parts, which causes negative caster and apart from being the force which steers front wheels strait when driving forward) a function of forcing front wheels to stay on axles when driving forward (I think this is the answer you were looking for @AutoBacon in this post )
• and many more details you will discover, if you decide to build my truck

 

I would also like to thank @nico71 for his great video series related to Western Star 6900 Twinsteer. It helped me to prepare more realistic grill, hood, roof elements and I believe overall better body of the KrAZ than in my first version of this truck. Thank you!

 

Attention! Two C+ L motors with decreased speed 3 times, so with torque increased 3 times, generate a lot of force which needs to be handled by rather advanced drivetrain. That is why there is a risk for 12T gears to skip or even be destroyed if wheels come across too much resistance due to very rough terrain. Please keep this in mind and happy off-roading!

 

Photos: (click)

 

 

Here you can see the original KrAZ-255 (1211 parts, 991 grams), the new KrAZ-255 v2.0 in standard configuration (1632 parts, 1220 grams) and the fully equipped and ready for everything version of KrAZ-255 v2.0 (2091 parts, 1525 grams):

 

Internals of the MOC, so drivetrain with differentials and diff locks connected with V8 engine, steering with working steering wheel and the winch

 

I hope you like it, if you have some comments or question, please ask. I will happy to answer.

Edited December 10, 2022 by keymaker

[Zerobricks]

What a masterpiece! Really like double driveline with differentials, it's a great solution to bring more power to the wheels and also to cancel out any torque acting on the axles. Also nice use of 9L links to keep the rear oscilating bogies from bending. I would just like to ask why did you use the rubber bricks in the rear, are they needed?

[keymaker]

57 minutes ago, Zerobricks said:

What a masterpiece! Really like double driveline with differentials, it's a great solution to bring more power to the wheels and also to cancel out any torque acting on the axles. Also nice use of 9L links to keep the rear oscilating bogies from bending. I would just like to ask why did you use the rubber bricks in the rear, are they needed?

Thank you! The rubber elements in the rear are added mostly to limit a little the range of movement and prevent tires from rubbing against 5 stud half beams when tires are in max positions. And I thought it will be some sort of stabilizer when rear tires deal with uneven terrain :)

Edited December 9, 2022 by keymaker

[jorgeopesi]

Great truck and even more great post it is a pleasure to read it and learn.

[AutoBacon]

It was really great following the story of development, I was always left in anticipation of how the solution to each problem is going to look :D The model looks great, it seems very polished and refined, and every part looks like it's meant to be there. Now the journey is over, what is next in the snow runner series? :D Is the chapter of 6x6 complete? :D

 

[keymaker]

5 hours ago, AutoBacon said:

It was really great following the story of development, I was always left in anticipation of how the solution to each problem is going to look :D The model looks great, it seems very polished and refined, and every part looks like it's meant to be there. Now the journey is over, what is next in the snow runner series? :D Is the chapter of 6x6 complete? :D

 

For sure I plan to create at least one representative from each type, so one model 4x4, one 6x6, one 8x8 and one 10x10. In addition I definitely will revisit my older MOC - Kirovets K700A - and I'll create it this time with instruction and in proper yellow color :D I'm not sure about scale yet, I'm wondering If I should go with small tracktor tires or to give myself more options and show how powerfull this tractor is by prepering it with middle tracktor tires (from Zetros). Time will tell.

And if chapter 6x6 is complete? Yes and no. One thing is the plan I described a sec ago and the second thing is the fact, that I'm very tempted to prepare KrAZ 255 in trial version, so super light, sturdy, with minimal amount of details and functions. Rough power and off-road capabilities, unstoppable no matter what.

Edited December 10, 2022 by keymaker

[lmdesigner42]

Very impressive MOC! Putting in such a complex drivetrain and suspension at this scale is quite a feat, not to mention all the extra features and details you included. Definitely a worthy tribute to Snowrunner. Looking forward to seeing what you come up with next.

[gyenesvi]

This really turned out to be a great model! I like both the amount of technical detail and how all is concealed inside a nice body. It would be hard to tell from the outside that it has such a complex drivetrain. I like also how the suspension is really functional, which is a big feat at this scale with all wheel drive. Great attention to details all over the place :)

[keymaker]

Thank you all.

On 12/19/2022 at 9:57 PM, gyenesvi said:

It would be hard to tell from the outside that it has such a complex drivetrain. I like also how the suspension is really functional, which is a big feat at this scale with all wheel drive.

The look sells - literally and figuratively. It is quite clear even observing this technic (in some part at least) forum. But for me functions will be always more interesting and will have higher prio when MOCing than creating maybe super nice looking, but still being just an immovable pile of bricks MOC.

That is why I'm still sharing here my MOCs, counting on some discussion about technical aspect of the model, about functions, mechanisms, designing problems and solutions for them. I'm perfectly aware, that everyone can judge if something is nice looking or not. But to judge and to be able to discuss mechanical stuff you need to have knowledge and understanding of it. Without it, any even most complicated feature will be just a next gimmick. I know, that those people with knowledge are rare, it is especially visible on yt or FB, when I see reactions and comments on particular models or functions. Here also those people are definitely in minority, but I think (hope) that this percentage is bigger than on yt or FB :)

Edited December 22, 2022 by keymaker

[Jundis]

Incredible work!

Looks and function go so well together here :-)

[Fluwoeb]

@Keymaker, glad you could take some inspiration from me! I appreciate your attention to functionality and also detail. My favorite detail has got to be the snorkels on the KrAZ-255 v2.0. Great job!