gyenesvi

Thanks for making this! I agree, actually this was my first idea too, but as I started thinking how I would build with it, I found that the second crosshole could be in the way in a couple of cases, either for the steering, spring mounts or some cross-connections, that's why I simplified to the single crosshole version. However, I really like the pin-hole on the back of your version, that has some potential of using it to fix it more solid if it's needed, even if there's only one crosshole, for example like this: On the other hand, I started playing with your version, and came up with this construction, which could be a solid one, if there existed a male CV joint with an axle (have you tried that?), as the top and bottom bars could be connected in the center, close to the wheel (no need for more connections on the front/back side): What do you think about these?

Thanks! Do you mean the part or the axle construction? Sure, I guess the part itself can be improved (and the axle construction obviously needs more connections to be solid). Sure, I can imagine that, but then the mounting becomes more problematic, and it protrudes more towards the center and you start losing ground clearance..

@efferman have you tried printing a part like this but with a towball socket in it instead of the pinhole? The closest I could make in Studio part designer is this: And I have been thinking about using it in an axle like this, where the width of the axle could be adjustable by replacing the thin 5L liftarms to 4L or 3L versions. Do you think that such a construction would be strong enough? BTW, I have checked out your Shapeways parts, lots of interesting stuff there. Was wondering if a diff with 20z gear is possible, it seems you have tried it already, although your desing is 2L wide, and I was thinking of a 3L wide version to fit into a 5x5 frame. How sturdy is that with those small gears inside? I guess they may be a bit weak for heavy-duty RC cars?

Thanks! Indeed, I like that part on the real truck, especially that the bed side goes well under the wheel arch on the outside, it's kind of unique, and I thought that's pretty easy to replicate with the existing parts. Thanks, I'm especially happy that I could do a fairly performing motorization without the need for custom electronics (as often is the case with large and heavy models).

It's true that that model seems to turn better, but it's hard to judge from the video what constitutes to that. One thing is sure, the model is much shorter, the two axles being closer, that instantly results in a better turning radius, even if the steering construction is the same. But maybe the actual turning of the wheel is also a bit better. He may be just using the PU app to control it, or he changed something about the construction, but I don't think he used something like @efferman's trick to actually increase the angle. But now that I think about it, that trick may work well with the overly limited app, as @efferman's construction in itself would result in a radius that is too much for the joints, but with the app not taking it to the limit, it might just be fine :)

Hmm, I didn't even think of that, I thought the angle was small enough to start with.. It's sad, because it limits alternate builds as well (if used with the stock app), even if they are built such that the wheel could not touch anything..

Hello Eurobrickers, Finally I am ready to present my latest MOC, the so called Bruiser Conversion of the 4-door Jeep Wrangler. The real thing is done by JK Crew, it looks like this (more awesome pictures here): The conversion includes pimped up suspension, a longer body on the rear part, turned into a pickup, and larger wheels. As for the scale, the real Jeep Wrangler has around 80 cm wheels, and the conversion has around 110 cm wheels. I thought this would be an excellent material for an alternate build from the 42110 Land Rover set because of the color match and the available parts (like those rear mudguards), and the 80 mm wheels of the Defender, and the 107 mm Lego tractor tires result in a good 1:10 scale match. I thought it would deserve the large tires and a motorization, all available in the set 42099. So I ended up with two versions: - Manual version, pure alternate build from 42110, with an optional raised geometry and large tires - RC version that is a dual alternate with 42099 I will present both versions below. They are identical on the outside, they differ in the chassis build and the gearbox / drivetrain. Manual version (42110 alternate) I wanted to build something from the Land Rover that has a more aggressive suspension with large articulation. I have been playing with the idea of 4-link suspensions on both axles, and the 8 A-arms in the set are just enough for that. However, I had to do it with short springs only, so I used similar geometry as the rear axle of Grohl's stadium truck, but with longer lower links on both axles. Furthermore, I wanted to build it in a way that works both with the stock Defender wheels, and with larger ones. So I built a chassis in a way that the springs can be positioned in two places, and the suspension geometry becomes lower or higher. Along with this, the front axle is also moved one stud to the front, to make space for the steering of the front wheel (just like in the real version). As such a suspension requires a lot of space (if you want large articulation), the actual useful space in the middle of the model becomes relatively short. I wanted to preserve the same functions of the gearbox as in the Defender, so I had to compact it. Taking ideas from the Pimp my Land Rover project I managed to create a version of it that fits into the available space, keeping the same layout of the controls. Furthermore, I have included a functional V8 engine (the real one has a V8 Corvette engine). One part that I struggled with a lot was the HoG steering, as it was quite hard to bypass the gearbox and the front seats as well. Finally I managed to do it under the seats, but I could not fit a functional steering wheel as the chassis structure that holds the front suspension was just in the middle of its way. The interior came out quite clean and also replicates the real one quite well I think. The seats are similar to those of the Defender, but I had to make them shorter, as the roof is also shorter: On the outside one key point is that the real thing (at least this version) has its doors made of steel bars (which gives it a great look I think). This is good as the Defender would not have enough green panels to build 4 doors, but the bar doors could be built (at first I did not think I could get such a clean look, but I am quite happy with the result). On the front, I reused some ideas from my Willys Jeep, but changed it to a bit more modern look. On the rear part, the fender piece was an obvious fit, and I wanted to emphasize the bed with system parts, which also came out nicely I think. At first the A and B pillars and the roof was tricky to make solid, as it is only built from a few liftarms. But the final assembly is super strong, thanks to the column in the middle that goes through the gearbox (that was a key structural element to make). The model can be lifted safely with the roof. Some side panelling was also tricky to get into place, but I am satisfied with the overall looks. The doors, the hood and the tailgate are openable. The spare wheel fits nicely in the bed. One last feature I could add thanks to the Defender parts is the front bullbar with a compact functional winch (with rachet mechanism). Here are some side-by-side images for a comparison. I think it works well with both wheel options. More info, pictures and building instructions are available on Rebrickable. RC version (42110 + 42099 alternate) For the RC version I decided to use components from set 42099 as it has everything required: XL motors for torque, heavy-duty CV joints, planetary hubs, more A-arms and hard springs for suspension and the few extra parts in black color. First of all, I wanted to motorize it in a way that I keep the interior and the functional fake engine as well. Second, I wanted to add a simplified gearbox. The placement of the battery was obvious in the bed, the steering motor would go onto the front axle, but the space required for the two (coupled) XL motors was less obvious. Finally, I could squeeze them under the rear seats, and place the gearbox in front of them into the drivetrain. As for the gearbox, incorporating a 2-speed one (hi/lo gear) was simple, but I wanted to do something more with the available parts. Finally, I managed to add an RWD/AWD switch. For this, gearbox routing is a bit tricky, going through itself through idler clutch gears, and returning later. Furthermore, the front and rear parts of the driveshaft rotate in opposing directions, which is resolved later by the proper placement of the differentials on the axles. It was really challenging to brace the whole gearbox properly so that the gears cannot skip anywhere, I had to rebuild and test it several times (those two coupled XLs have a lot of power). On the downside, I suspect the relative complexity of the gearbox add some friction to the system. As I wanted to maximize ground clearance, the front axle was tricky to build, since the planetary hubs can only be connected with ball joints when steered. For this, I applied the trick used by other as well, that slants the lower A-arms a bit, resulting in very slightly non-vertical front wheels, but it is so negligible I bet you'd never notice. The resulting axle is fairly slick, I am happy with the result. As the steering motor made the front axle higher, the functional piston engine had to be minimized as well, and I could only do a mini V6 with the available parts. Unfortunately, this small construction does not run super smooth in a V configuration (sometimes the 2L liftarms in the main shaft kind of collide into the half pins that make up the pistons for a moment, instead of smoothly pushing them up; the inline configuration with the same technique works smoother). For this reason, there is some friction resulting from driving the fake engine as well. Here is the final chassis, and one more image about the ground clearance at the rear: Although the final gearbox construction is strong enough not to let the gears skip, there is one weak link: the driving ring can move out of the clutch gear under very high torque (although in my tests the model sooner went up the wall if not blocked). This is because the gear stick does not firmly hold it in place. However, it can be solved by fixing it into one position with a linkage coming out of the center column. This issue made me think how much more powerful it could be if the gearbox and the fake piston engine was bypassed, and eventually led to the construction of a heavy-duty variant (in which the gearbox is still kept, but instead controls the speed of the fake engine, when not in neutral). The heavy-duty variant is further geared down a bit to have even more torque. It can climb almost everything if the ground clearance permits, as you can see quite a few cases in the video. A few more images about the whole model: More info, images and building instructions are available on Rebrickable. Let me know how you like it! Cheers, Viktor

Well, I actually experience the contrary, I have built a lot from 42099, and never experienced this. I have a build right now, just checked it, and the steering rack is moved to the limit when it's on a flat surface (contrary to the Zetros, just compared the two on the same surface). Thanks, good to know. Have you by any chance reported this to TLG?

I agree with much of what has been said before: modularity can help with a cleaner structure that may resemble the real thing better, easier assembly and disassembly (yes, it's very useful when iterating on something building it again and again) even better building instructions. However, I do not try to enforce it just for the sake of it, especially when there is not enough space (like always) or when it would hurt structural integrity. This. Check my signature :) (no, I did not put it there now). I apply this a lot with Lego, and also in my work when writing software (I am a software engineer). It helps a lot to clean things up. And I agree with @nerdsforprez that the right way to understand it is to 'remove all superfluous structures'. (sure, some things are there for decoration..) But in general, this is where I stop with my models, when I achieved all I wanted (functions, looks), not more.

As I am trying to build something from the Zetros, I discovered an(other) issue with the steering calibration, wondering if anybody else has seen it too. I was experimenting with a different steering system (not based on gear rack, but on a linkage system), that would require turnig the motor 45 degrees instead of 90 as usual with the gear rack. However, I have noticed that after calibrating with hard physical limits, the motor actually rotates much less then the limits would allow, something like 25-30 degrees at most. I have also tested my build with a custom profile in the Powered Up app, and with that it works quite well, after calibration the steering motor moves all the way to the physical limits. I have gone back to rack based steering to see if it had something to do with my build, and I found that even with that steering mechanics, the motor does not move all the way to the limit after calibration, but the difference is less visible (I guess 15 degrees less movement is less noticable when starting from 90 degrees of limit than from 45 degrees). From this I conclude that this may be a bug, or there may be some sort of (over)protection in the Zetros C+ profile that makes it steer much less. That could explain part of the noticably bad steering radius of the Zetros (apart from the fact that the CV joint in the wheel hub cannot take a steep angle and that the Zetros has a long distance between the axles). Has anybody observed something similar? Can somebody confirm that he steeringg rack does not always move all the way to the limits? (Best seen when tested on terrain that puts some friction on the tires so they are more difficult tu turn than when moving freely in the air).

This will be done automatically by the Control+ app for you, so it does not really matter where the actual functions are positioned in the gearbox. Though I wonder how fast it will be to switch between functions. I wonder whether this is justified for example by the weight of the blade, would a faster gearing result in insufficient torque to lift it? BTW, thanks @kbalage for the compact review(s), I like that it only contains the really interesting pieces of info.

While it's true that in 42099 the steering rack itself is one stud closer to the center of the wheel, there is a limiter on the other side of the axle, which is one stud further (so exactly the same geometry as the Zetros), which limits the movement to 1 stud laterally, so the result is exactly the same angle as in the Zetros. It simply has a smaller turning radius because it has a shorter wheel base (the two axles are closer).

@efferman If I understand correctly, this increases the movement range of the steering rack by half a stud. According to my own tests, this is already too much for the CV joints, at that angle there is already considerable amount of friction on them (the wider part of the neck of the male part pushing against the edge of the female part, there's a 'hump' on every turn); sure they will turn with force, since the motor is strong enough to drive it, but I believe that they would get a lot of wear over time, especially at higher speeds. To check this, you should try to disconnect it from the drive motor so that you can spin it freely, and spin the hub from the wheel side to feel the friction. What I found is that roughly 1/4 stud more space for the movement of the steering rack is still ok, but 1/2 is just too much unfortunately. Let me know what you think.

I have posted free building instructions for this model on Rebrickable: https://rebrickable.com/mocs/MOC-86341/gyenesvi/8830-remake-moon-buggy

Thanks for the answers, I have been thinking exactly in this direction, but some crucial detail was missing, but now I have figured it out. It's probably something like @Gimmick is talking about, although I am not sure exactly what he means, but here is my solution. As opposed to an 8-speed gearbox, which has only a single output with different speeds, something must be fundamentally different here, and what I have realized is that in the generic case of up to 8 functions, you need not just a single 2-output gearbox and a single 4-output gearbox, but you need two of the 4-output gearboxes after the 2-output one. The 2-output one is which changes once after every 360 rotations of the 4-output gearboxes, and basically selects which of the two 4-output ones are active. So theoretically the drive part is not too complex, maybe the switching mechanism is a bit more involved, but that does not really effect the performance. The whole thing would be probably quite big though. On the other hand, the special case of 5 outputs gets more simple, as one of the 4-output gearboxes can be left out, simply using the second output of the 2-output gearbox without further multiplexing it. So that would be somewhat more compact, although probably still large enough.

I don't think he put it wrong, step 24 flips it upwards, otherwise it wouldn't be doing anything there. I think the friction is just like that, I remember wondering the same. I think it didn't matter at the time, since it's a manual set, and large enough so that you don't really feel it when you push it around.

I totally agree with this. But it only gets worse, as they are not even really compatible SW-wise. I bought the Mindstorms set, as I saw great potential in the rechargeable 6-port hub and the motors, but it turns out that the Powered Up app is not compatible with the Mindstorms hub. I learned that they use different Bluetooth technology for remote control (Technic hub uses more recent BT Low Energy, while Mindstorms uses old BT technology??? (although it does contain some BLE HW AFAIK), and does not use the Lego Wireless Protocol as the Technic Hub). It just seems a bit uncoordinated for me, lot of potential left on the table, all the HW seems to be there without proper SW, which is annoying.

So at least in theory it is possible with current pieces? Do you have some reference to see how it would work?

While I agree that LAs are more precise and hence more playable, I would have loved to see an RC pneumatic solution with the new PU small motor for switching valves. Also, the 6-port rechargeable hub from the Spike / Mindstorms set applied to the Technic lineup. Although, if I count it right, drive plus 4 functions requires 7 motors at least (2 for drive, 4 switchig, 1 for the pump, right?). But other solutions for avoiding more than one hubs would have also been interesting, such as the separation of the control unit from the battery, or some way of connecting two identical motors that are driven together to a single port. I have already asked in the CAT thread if anyone actually sees this even theoretically possible (with a single motor for drive and one for switching, I don’t) and so far I did not get any solutions.

This. Another opportunity missed for improving the range of available parts. The review is really nice, even with the too dark background, the photography is great, and the summary is to the point.

This is somehing like what I meant to say. I don’t mind lack of perfection, a set is totally okay if I can build something else with functions that I like better. But sometimes that needs the right parts, like those suspension parts you mention and missing links in the PU electronics system, and I feel that Lego is not too fast grabbing the opportunities to introduce those. This year’s off-roaders don’t innovate too much, and the new parts in this set are nothing revolutionary either. I could have imagined a small motor for gearbox switching for example.

My problem is more the direction where Lego is NOT going. This behemoth could have been a good opportunity to release for example a 6-port hub, like the Mindstorms one (or even just reuse the yellow one from the Spike prime set). Then two more functions could have been added, like a ripper tilt and some lights (which could have been a really nice addon to a construction machine). I guess the ripper tilt was excluded because it does not add too much to the play experience, and the fancy ladder is probably going to attract more 18+ buyers..

Low ground clearance on off-roaders. And bulky live axles.

Oh, I mixed them up with the LBG ones, those are the ones that don't have then. So it's a different system than on the Liebherr then? On that one they could rotate.

Those tan ones don't have a + hole in them but a round one, so they can rotate on the axle.