Teo LEGO Technic

Hey guys! I present my new model, a BuWizz 2.0 powered Baja Truck! It features: Independent double wishbone front suspension, with servo steering and positive caster for better return-to-center Live axle rear suspension, powered by a buggy motor and BuWizz 2.0 My goal with this truck was to make a small, lightweight truck with excellent offroad capabilities and smooth suspension travel, while also giving it a realistic look with the least number of pieces. Overall I'm quite satisfied with the result! Here's a video: And more photos: More photos can be found on the BrickSafe page: https://bricksafe.com/pages/Teo_LEGO_Technic/baja-truck Hope you guys enjoyed! -Teo

Got it, looking forward to more progress, that axle looks really sturdy I wonder if it wouldn't be a good idea to create some shared system of tracking what various transmission systems can handle in terms of torque before breaking or slipping (3L U-joints, old/new differentials in the 5x7 frame, etc). For example, with my current MOC, I would also be interested in knowing how much torque the 3L U-joints can take inside the ball joint.

For sure yeah, it's currently slipping under pressure so I was planning to strengthen it. Do you have an idea for a better diff lock setup? If it was more compact, I could turn flip the axle around and that would remove the need for the gears entirely, just stick the M-motor directly into the actuator following the perpendicular gears. As it is, the diff lock system protrudes too much and would ruin the truck's approach angle if it was at the front.

Great start! What's the size you had in mind for the wheel base? That looks like a pretty short axle, or are you going to use a four-link suspension setup?

After a lot of prototyping (and I mean a lot ) I finally have a working version that is pretty close to the final version of the front axle. Drive is using the new differential, in the 5x7 frame for maximum strength, steering is using a small actuator, placed at 2 studs from the pivot point for sufficient steering range of motion, and differential lock is using a clutch operated by a small pneumatic piston, shifted away from the differential with two sets of gears, to eliminate friction between the clutch and the differential hub. The portal axles are secured very well, both top and bottom, and the only thing still needing some work is some reinforcement on the gears at the front that transmit power to the M-motor for steering to prevent slipping, and some work on the diff locking system, perhaps strengthening it or moving it in a new position to increase ground clearance. Thoughts?

So here's the current progress. The front axle continues to be a challenge, but once I figure it out, the gearbox, diff lock mechanism, and chassis will be relatively easier. As far as the steering axle is concerned, I've broken it down into drive, steering, and differential lock, to investigate and compare my options: Drive: New differential in a 5x7 frame Zetros style, without frame, and geared on the side to allow space to for the clutch to enter the differential on the side Of these two options, I chose the 5x7 frame, because I want the perpendicular gears to be as secure as possible to take the toque I'm planning to put on it. Steering: Using an actuator: Small actuator - more space efficient, but has to be within two studs of the wheel hub pivot centre in order to have enough range of motion Large actuator - takes up A LOT of space, but can be much stronger, and has much more travel Worm gear - use a rack and pinion connected to a worm gear Either way, the motor powering the steering can either be on the axle or chassis. Of these options, the large actuator simply takes up too much space, so I plan to go with either the small actuator, or the worm gear. Differential Lock: (given 5x7 frame) Clutch: "Classic" lock system with clutch directly connected to differential causes some friction between diff and clutch, but is workable like @2GodBDGlory said Use more gears to push the clutch further out, and have less friction Clutch movement: Small pneumatic actuator Zetros - style with orange screw piece Of these choices, all are available, as none have any clear advantages or disadvantages. My one question to you guys is: what do we think of reducing the gear ratio further after the diff, and increase the ratio before the diff, to take pressure off of it in terms of torque? Is this worth the effort, or does the added friction and complexity not make it worth it overall? Hope I haven't rambled on too much

It may work, but the issue is the triangular shape of the diff causes uneven friction, which will be a worse issue for the MOC at higher speed (when the gearbox is in higher gear). It's a challenge for sure, hopefully I have a solution for you soon I don't sadly, gonna have to work with the regular rims. BTW more examples for driven, steered, diff locking axle builds are welcome!!! Thanks @Lukes_Brick_Studio for your input so far

Good idea, I can also probably stick an XL in each and see if it holds. Sweet truck! Very nice system for the front axle, I saw the same portal axles used by Functional Technic on his Unimog, they're very compact and sturdy https://www.functionaltechnic.com/2020-08-30/unimog-406-with-diff-lock-and-portal-axles My only problem with them were the use of the CV joint that limit the steering angle (an issue with the LEGO Zetros for example that I want to improve upon). It seems lots of people use pneumatics for diff locks, that might be something I should look into.

So here's what I've got so far. As it turns out I may have bit off more than I can chew, but with some patience and help from u guys, I think it's achievable. Like I said this is my most ambitious build yet. As of now, the width of the axle is just what i want it to be, using Zblj's custom portal axles to save a stud on either side compared with the Unimog set portal axles. Total reduction is approximately 11.6:1 which is going to provide a ton of torque, and all the gearing is solid and should be slippage-free . With this set-up (not yet strengthened by any means), the new diff sits inside the 5 x 7 case and therefore is as sturdy as it can be. The issue is, unlike, the older one, with the new diff there isn't enough room for this trick, so more gear are required to transmit power away and provide enough space, which takes up extra room: And if I want to do it the way it is in the Zetros set to save space, I think I might run into the same issue of gear slippage, due to the lack of the 5 x 7 frame: So my question is, which gear locking mechanism do you guys think I should go with: the current one, with the clutch outside the differential, or the Zetros version where it sits right beside the differential? Also, does anyone know of other builders who have made a steered, driven, and locking front axle? I could get some more inspiration for how to fit it all in, I'm pretty stumped at how to put it all together in a nice solid fashion

Honestly same, if it's worth doing it's worth overdoing in the words of the immortal mythbusters I looked this up and I can't find it, what is UGH? Tonight I will continue working on the front axle, probably the most complicated part of the whole build. I have a couple different ideas for how to fit all three functions in (drive, steering, diff lock), and I'll post the prototypes to get your guys' feedback .

What's OP? I'm choosing a trial truck mainly because I want space for the gearbox and differential lock mechanisms. Yeah I'll either do a small actuator or a worm gear.

Sweet crawler!! I guess the small actuator remains an option... That could work, I'm looking at the U3000:

Good idea, worm gear it is. The Chilli Crawler is indeed a great model, is the worm gear attached to an 8-tooth or 24-tooth gear I can't tell?

Sounds good, I'll post a photo of the front axle as soon as I finish a prototype. I'm also a Unimog fan, so we'll go with that. Seems like it's unanimous: actuator > servo. For a MOC roughly the scale of the Zetros you don't think the small actuator would do the trick? I'll try fitting the large one in and see how that goes.

Interesting idea. How bout an M-motor with a small linear actuator mounted on the axle? I've been trying to decide whether to place the steering motor on the axle or the chassis. The diff lock motor and drive motors have to be mounted on the chassis to transmit to both axles.

Great review! Personally I love pick-ups and so I like this set, but it isn't my favourite either

Hey guys! I'm trying something new this fine Wednesday afternoon, my first WIP topic. I always present my models fully built, but this time I'd like to get feedback and advice as I build, to make a better final model, and to learn more from the Eurobricks experts as I go . So please feel free to expound productive criticism, and here we go! For this model, I want to build a 4x4 trial truck that's loosely based on the new Zetros in its diff lock system, but otherwise quite different. The scale is going to be such that it fits with the CLAAS tires, and the main features I want are a combination of a heavy-duty 2-speed gearbox (based on Sariel's: http://sariel.pl/2011/02/2-speed-heavy-duty-linear-gearbox/), combined with diff locks based on the Zetros system, on both front and back axles differentials, with no central diff. This will allow the truck to travel fast in high gear with open diffs and good u-turn capability, and slow and powerfully in the low gear with closed diffs for offroading. To sum up, these are the desired functions: -Precise steering with servo motor -All wheel drive powered by 2 XL's -Two speed heavy duty gearbox -Differential locks on front and rear axles with M-motor -Power by BuWizz -No chance of gear slippage/damage anywhere along the drivetrain, steering, or locking systems For starters, what do you guys think is a good truck to model? Perhaps just a good old Mercedes Unimog? A Russian Ural trial truck?

Great, thanks!

Out of curiosity, I'm also considering a rebuild of the chassis, what are some of the best steered live axles with diff locks that have been built in the past? The scale is the CLAAS tires, with a goal of bearing very high torque.

Great axle build! Just wondering, is the bar at the front for controlling the steering? I imagine so, because there's no rack and pinion.

I've never seen a bike that actually balances in LEGO before, the battery box being moved by the servo motor is brilliant

Makes sense, yeah. I like how you put the L motors directly in the rear axle, replacing a differential. Minimal power loss

Nice truck man! My only thing is I'm surprised the BuWizz with an RC motor doesn't work, I just finished a very similar build with BuWizz + RC and the power never cuts out.

That makes sense. Your average customer is probably more interested in builds that won't wear the parts, than in maximizing performance.

Great Ferrari, reminds me of the one from Scent of a Woman My favourite part is the grey curved parts you used for the engine design, they look great