Madoca 1977

For now I’m not going to share new models until I finish physical building and making instructions. Because I have left many abandoned projects which I could not complete. Currently I’m working on a new 4x4 model. It will be shared in a few months. (Not in a few years!)

Thank you for building! I chose those old/new gears on purpose. The 20t gear on steering link should be old(double bevel) one. New azure square gear touches 7L liftarm when front axle articulates to the limit because of larger diameter than old ones. The 12t gears under the chassis should be black(double bevel) ones. They have smaller diameter than new blue ones and rounded edges. Which means slightly better for ground clearance.

I built that one last year. It was highly experimental model which had front and rear independent suspension with self-locking differentials. Instead of 2 speed gearbox, it had M motor for locking 3 differentials simultaneously. I didn't share it because of poorly outdoor performance. But now I'm thinking if I combine those mechanics and Blazer's together, off-road performance would be much better. You are absolutely right. Actually I used old red 2L driving rings during WIP because I had dozens of those parts. The only reason I used new (and still rare) 2L driving ring was to avoid discontinued parts in 2025. Also, I got 42209 as a donor for this MOC.

Since all gears and shifters are in 5 studs width, using shorter 2473(2L) was the only choice. If you use 18947(3L), you also need to replace red differential to older DBG one which has smaller housing. My Dacoma 4x4 model has rear diff lock using 18947. With major modification to both axles, you may use 18947 with DBG diff gear. I think performance would be almost the same thanks to planetary hubs.

Gears are meshing quite smoothly. But gear tooth touches at very small area(A) compare to normal square tooth gear meshing(B). Transmitting high torque will damage gear teeth. In this MOC, transmitting torque (diff-locked) situation is limited. So it worked. By the way, I also learned interesting/annoying size difference of those gears. Maybe you all have already known it though. I tested flat fenders and they fit well. But with this chassis setting tires touch fenders when suspension articulate to the limit. So I used curved one which have more space in it. (This time I stick to maximum suspension travel.) I think widen the body 1 stud would be solution. Instructions available at Rebrickable! I know sometimes my photo-sequence instructions would be hard to follow. I'm very sorry but I prefer somewhat challenging instructions (back in 1980s) to recent "18+" instructions.

Thank you for your kind words! Since I had abandoned old projects, I will have to build everything from scratch once again including Land Cruiser 80. But I learned there are plenty of useful new parts available nowadays. So new one could be better in terms of both functionality and appearance. As for the model, I found this kind of self-locking diff was not enough for driving on low-grip surface. It should be remotely locked when needed, or some kind of brake lock differential like Suzuki Samurai and Jeep Wrangler.

Hello, everyone! Here is the first creation I have completed in 6 years. I used only pure LEGO parts and Powered Up components. Weight: 1475g (including 6 AA batteries) Features: - 2x L motor for propulsion - 1x L motor for steering - 1x M motor for High/Low gearbox - Self-locking differentials - Linked pendular suspension - Detachable body and removable top - Openable hood, doors, rear hatch and tailgate Video: The main feature is self-locking differential system. Basic idea was the same as I put into modified rm8's Toyota Hilux in 2019. When one axle articulates to the limit, orange shifter rotates and diff lock engages. This time I also added center diff lock which engages when axle linkage moves to the limit. Since both axles and the linkage between them move together, all three diff lock engage simultaneously when suspension couldn't soak up the bumps. Rear suspension travel is longer than front because the pivot of linkage is off-centered. Additionally, rear axle is positioned slightly lower than front. This can be done thanks to the flexibility of some connection point. Steering system has a pivot on the same axis as roll center of front axle. Therefore suspension movement barely causes bump steer. The upper body looks narrow because of one stud width of the edge of beltline like 42213 Ford Bronco. Last but not least unique feature is the way of fixing body to the chassis. First, hook the back side of grill on the front end of chassis. Then switch four levers to fixed position. In a way, this model is the successor to my Jeep Wrangler built in 2017. I tried to pack more features in the same wheelbase as Jeep. Eventually its heavier weight required the use of planetary hubs. Which means the model became powerful but very slow. Unexpectedly off-road capability wasn't so good. Since diff-lock system depends on the movement of suspension, it didn't work when any wheel lost their grip and started spinning even on a gentle incline or slippery surface. But I am happy with the result because I realized that I still could make something even after losing love, money and lots of hair! Building instructions at Rebrickable.

Fortunately I had a chance to see you driving this monster in the event. Amazing model. I especially love the bodywork. It looks like a Moby Dick, but also runs unbelievably fast!

That picture is rm8's studio. I'm surrounded by HIS creations! Anyway, I drove this truck in Russian community event. Pictures and videos of the event can be seen on the site of LEGO Technic Russia. From now building instruction is available at Rebrickable. And the picture below is how it looks with 120mm tires. I think these RC4WD tires are the same ones as Sariel had used for his Crawler and Baja Truck.

Last night I visited the studio of my friend rm8. We made a review of my Monster Truck! Now we arrived Moscow and will join the event of Russian Technic fans. Instruction will be available after coming back to Japan.

Thank you for watching! I wanted to use dual shocks only because its look. As the black version does, using single hard shock for each wheel is enough to hold the body. But dual soft shocks was a little bit unstable.

Hello everyone. As a monster truck MOC was one of my earliest creations, the time has come to remake it! Weight: 2030g - Powered by 2 SBricks - 4 XL motors for propulsion - 2 Servo motor for steering - M motor for switching steering mode (normal/crab) - M motor for raising front hood and rear bed - LED lights for headlights - Openable doors and tailgate Those old-school power functions components still work sufficiently in this MOC. The body was inspired by 80's monster trucks made from lifted and modified Ford pickup trucks. The under structure was designed for robustness. Eventually it looks more like modern tubular chassis. There could be multiple options for the sets of dual shocks. (Hard/Soft, Hard only, H/H, S/S) Vertically placed M motor moves Polarity Switch connected to rear Servo motor. Horizontally placed M motor is for two functions. Front hood opens via worm and 24T gear. On the other hand rear bed is raised via small actuator. That requires two driven axles of different torque and rotational speed for each side. Center differential enables single motor to transmit the power to both sides. One of the benefits of portal hub is easy to change gear ratio. Body parts could be replaced with different color scheme, though they are not fully modular. On November 2nd and 3rd, Monster Jam live was held in Japan for the second time. I did go to the event and took photos of amazing real monster trucks and drivers. Thank you, Bari Musawwir and Neil Elliott! Building instructions available at Rebrickable.

2: 10 5: 6 4: 4 7: 3 1: 2 8: 1 Actually I fell in love Seasider’s custom sticker of technic pin flying over the mars:)

Nothing has changed in using parts and building results. Just a few parts were connected before they should be in older 24-25 steps photos. Perhaps builders who noticed that may jump step 23 to 26 and follow the rest. Don’t worry, I see you built it perfectly right. Thank you for building!

I am very sorry, I rechecked instructions again and noticed that I have used wrong photos for step 24-25. I just fixed it. If you have already copied early version of instructions, please check the (tiny) differences and use correct photos. Turns our concentration on working became lower than in my 30s...

3810g is more than 1kg heavier than the old one. The inclination in the last part of video is 40 degrees. Surprisingly there was no gear clicking in that scene. I think because all wheel (8 pairs of bevel gears) equally shared the load.

This odd suspension linkage was necessary to make chassis narrower because steered axles with portal hub move wheels deeper toward the center of frame. For years I’ve been searching how to conquer terrain and gravity. And I’m still looking up your 8 XL powered FOX 8x8x8. This is yet another answer to it.

Thank you! For me sharing MOC is purely enjoyable. Making money is not. Even though I’m not rich at all. The truth is, I’m a stubborn cynic who wants to go against the grain.

I’m sure that will lead to even more clicking because it is much heavier and putting larger tires.

Hello everyone. This is my second Tatra model.Comparing to previous Tatra 813 Trial Truck built in 2014, it is bigger, heavier and a little bit faster. Weight: 3810g Length: 62.4cm Width: 24cm Height: 25cm -Powered by 2 SBricks -6 L motors for propulsion -2 M motors for steering -M motor for 2 speed gearbox -Working steering wheel and V12 engine -Openable doors, front grill and roof hatch The model was specifically inspired by a unique truck of Jansa Team participating at real truck trial events. I tried to replicate overall look as possible without using any stickers. The cabin became one stud longer than it should be. Also using many system parts was somewhat compromising as a Technic builder. This time I omitted offset axles because symmetrical structure was more robust and efficient. Each side of half axles are independently driven via two parallel drive shafts. That enables slightly smoother turning than previous one adopted single drive shaft. Body parts are removable by pulling out both seats and two 5.5L axles behind the rear bed. When I completed the chassis early in 2018, it never came to my mind that LEGO would officially release "game changing" planetary wheel hub. Admittedly those bulky half axles using portal hub look outdated in 2019. The core of chassis contains bunch of L motors which I called 'Six Pack Abs'. The gearbox is simple yet packed 16 gears into tiny space between L motors. Although suspension mechanism is not like real Tatra, pairs of swing half axles move like real one. That realizes good off-road capability. The steering angle of 1st axle is twice as 2nd axle. Two hard-coupled M motors move 13L gear rack via dual pinion gears. For more powerful steering, I did not use white clutch gears. Consequently geared down motors keep rotating and make clicking noise when gear rack reaches end position. After all, this MOC ended up to be just a big truck driven by old technology. (Strangely it sounds like aged Tatra 813 in modern truck trial events...) Still I am happy with the result and sharing another massive 8x8 model. If you like it, feel free to put colorful stickers on it, make alternate cabin design or build more accurate chassis with new hub parts. Building instructions available on Rebrickable.

Thank you for your kind words! Actually this gearbox was inspired by rm8’s idea of assisting rear axle by another motor. It is always interesting to make it simple, effective and reliable. Some models without instructions are still in my to-do list. I will fix or improve them like I did for Dacoma truck.

Hello everyone! Thanks to the purple Titanian, it took 18 months for coming back from yet another dark age in my life. Now I am here with yet another pickup truck. Design was inspired by Ford Raptor, Dodge Ram and GMC Sierra. Dacoma 4x4 Redux Weight: 1360g -Powered by Sbrick -2 L motors for propulsion -Servo motor for steering -M motor for two speed gearbox, (sort of) limited-slip center differential and lockable rear differential -LED for headlights -Openable hood,doors and tailgate Video: https://www.youtube.com/watch?v=qMUH1YmF1F4&t=1s This is an improved version of my Dacoma pickup truck and TLC 80. I could not finish building instructions for them because they had fatal drawbacks on their drivetrain. In low gear, bevel gears in center differential often skip and pop out by the torque of propulsion motors. To make it reliable, it was necessary to reduce the stress on center diff while handling higher torque in low gear. The gearbox works sequentially. (1 - 2 - 3 - 2 - 1) 1: High - 2: Low - 3: Low with rear diff lock In low gear, center diff works like limited-slip diff. In high gear, two L motors are coupled and rotate center differential together. Front and rear axles are driven via open center diff. In low gear, only one L motor rotates center diff. Another motor is connected only to rear axle. (In other words, it just supports rear half of drivetrain.) Which means rear half of axle in center diff is (nearly) locked. That means front half of axle in center diff is locked as well. Maximum suspension travel is not as long as older Dacoma truck. But new one articulates better thanks to softer front suspension. Years ago I happened to get some rare blue parts from old sets. So I could build it in blue. With a few tweaks, it can be built in white, orange or black. Building instructions: https://rebrickable.com/mocs/MOC-25520/Madoca1977/dacoma-4x4-redux/#comments I hope you will like it. And I will work hard not to take a long time for sharing next model.

At first I thought putting fourth gear into differential would prevent gear skipping because of tighter meshing than three bevel gears. But I noticed that floating fourth gear was just lying on two inner bevel gears, which means there would be no tighter meshing between them. Then I realized that the point was not the fourth gear but inserting a piece (with pin hole) between two inner bevel gears. That piece can hold both axles almost in line. (Of course it also prevents gears sliding inwards.) Thus, inner three gears would hardly disengaged. ...At least on paper. Actually higher XL torque broke the theory. But I think it is still a better way to reinforce 4L differential. Also 1L technic brick is better than 1L liftarm because its slightly thicker and square shape leaves less room around it.

You always give me inspirations. Especially I like the way of pure technic (without slack) building. Thank you for sharing great ideas! In this case, I used a shock absorber instead of rubber bands for 90 degree stepper.

Hello everyone! It has been a while since I last posted on this forum. In November I tripped to Russia again for participating LEGO event held in Moscow. This year, my friend Rm8 gave me the opportunity to make video review of my models together at his studio. You might have seen the review of Jeep Wranglers. And this is the other model that I first had a presentation to Russian builders in the event. Toyota Land Cruiser 80 Weight: 1520g -XL motor for propulsion -Servo motor for steering -M motor for front winch -M motor for two speed gearbox and center/rear differential lock -LEDs for front and rear lights Everything started from the issue of center differential in the drivetrain of my previous Pickup. After driving on serious off-road I found that bevel gears in center differential got damaged and often slipped. So I tried to find the way to reinforce gear meshing in 4L differential. In conclusion, I still have not succeeded. Every attempt was not strong enough for transmitting the torque of geared down (3:1) XL motor. In extreme situation floating fourth bevel gear was pushed out by the force of twisting differential housing. I was even hoping new red 4L differential could hold four bevel gears tightly in it, but it does not. So I used the second one in the picture above. (just insert 1L technic brick for holding both side of axles tighter) While attempting several ideas of transmission, I was building another 4x4 model using three differentials. Eventually it became the most advanced version of my SUV models yet being over complex and less reliable. The main feature is sequentially working gearbox and diff lock system. I used Didumos69's Compact 90 degree stepper idea for switching four modes. (0→1→2→3→0 ...) 0: high gear 1: low gear 2: low gear with center diff lock 3: low gear with center/rear diff lock You can see it working in the second half of this video filmed by Rm8. I used M motor instead of Servo motor for switching modes because there was no space for it under the driver's seat. It is necessary to stop motor rotation when stepper axle comes to the right position. Actually this model is too heavy for real off road driving. Center differential often suffered the load, and it was a little bit tricky to operate sequential mechanism precisely from a distance. So I built a lighter and simplified version only using XL and Servo motor. It has softer rear suspension, manual gearbox and center/rear limited slip differential. (Weight: 1260g) Ironically it worked better than fully equipped version even lacking diff lock system. Thanks to soft suspension it has better axle articulation. All four tires well kept contact with the ground. I put it on rocky surface just for taking pictures. Actually it could not climb over those rocks, though. I am making building instructions for both versions. I hope you will like it!