amorti

I'm going to build this once my bricklink orders come through :) Considering Porsche wheels are ridiculously expensive and I don't have any, would it work on swirl wheels, or Landover wheels? They're the same diameter 81.6mm so ground clearance should be the same. Both have narrower tread, however both still seem to have the offset needed to get the rims at the same overall width? http://wheels.sariel.pl/ Any others which are (lots) less than 25€ per corner and would be suitable? I actually prefer a higher profile tyre to give a bit more cushioning when driving outside. Thanks :)

He's fitted two control+ hubs into a car based on Bugatti rims. I guess he could afford 30€ for a servo motor, but he doesn't need it, because control+ L motors can be used as servos, and they're much better than PF servos.

To give an idea of the extra power these motors are drawing, if you give full gas from a standing start in Ludicrous mode, it'll trip the safety immediately even with two freshly charged buwzz units. Original Lego L-motors don't draw so much power to do that. I fully expect they're cheaper-made than Lego motors and waste more in heat and friction, but that extra wattage has to be going somewhere. Anyways, some more mods have been made. Sometimes Claas tyres just aren't big enough... These are eBay China-special 1.9" x 120mm RC tyres. With them on, the model drives quieter as they're comparatively very soft rubber, relying on the foam inside to keep their shape rather than a hard rubber casing. The circumference is about 12% increased, so speed should increase by about 1/8 if the motors have the power for it (the Chinese motors do have enough juice for that, I don't know about original Lego motors). It now only barely touches the ground at full suspension compression, and has a little more clearance for e.g. driving up kerbs, which it will easily do. I also added LED strips front and rear. With all that extra power and extra grip, you can pop bevel gears at will by rocking the car back and forth in Fast mode. It's not a limit of the materials (yet) but the power exposing flex in the bevel housing. I haven't broken any since doing this modification though. Swapping an I-beam into the rear of each swing arm gives more solid support for the rear of the prop-shafts than original solution. An extra 5L beam goes a little further still with form locking; the price is the swingarm then becomes one unit longer, but this isn't an issue for clearance. The prop shafts are a 2L axle straight into a 2L axle connector, then an 8L axle which goes through a pin with hole connector being used something like a prop-shaft centre bearing. The 8L axle is better-supported at both ends than the original solution, eliminating that flex and saving your bevel gears. You do lose the mechanical stop which was present on the 5.5 axle in the original solution, but for me it's worth it, and anyway it takes a fair while to creep any noticeable distance. If it does creep out, it'll escape the 2L connector first, but not fall out of the vehicle entirely due to the 1L bush. I guess you get enough warning and no catastrophic failure occurs. I guess using an 8L axle with end stop would make it marginally quicker to change out a bevel gear if you still manage to break one. You might even manage to change out a pair without removing the wheel from the swingarm - I don't know, I haven't had to try. Thinking about it, there's now no reason not to use a 10L axle to cover the whole length of the prop-shaft. I may yet do that, and add 2 more bushes in place of the 2L connector to give more clutch on the propshaft. Again, thanks to @Didumos69 for the awesome design. It's a wonderful model, by far my favourite in the collection, and I just love to play with it, and make these little tweaks. Edit: I did change for a 10L axle as a prop shaft. It does have more clutch, it's also a pig to assemble.

Might be of interest to non purists:

The proportions feel off; wheels and arches are too big for the model. I guess it can be a tuner car in that case.

I do like the video! 9m well spent.

+1 to what they said. Awesome creation, can't believe how well it moves for the size.

Seems like it'd be easy enough to drive the steering wheel off the back of the servo and have it move with the steering, maybe a rubber band transmission?

Brickcontroller2 is what you need. It'll handle pf and pu systems, and it's very easy to program using whatever Bluetooth compatible gamepad will link up to your phone. Also why not KISS? This project has been done already. https://racingbrick.com/2018/01/lego-technic-42078-mack-anthem-test-rc-mod-images/

The controller you mention is really limited. Two paired digital buttons. What can it do? Better you get each of them a $20 android gamepad, this should allow control of multiple hubs by one device. I think. There's a bc2 thread to ask that question.

No shots intentionally fired your way mate. Just aiming at a general hypocrisy on a forum where people accept selling instructions for MOCs at $20+ a throw, listed using car brands they didn't license, rims at $60+ a set, using IP they didn't license, but we can't mention Lepin due to IP theft. More of an invitation for anyone who thinks the rim site is ok to take a look at what they really believe about IP, and whose is worth protection.

Agree with @Touc4nx. The 7L wishbones are going to be a problem. Better if you make them 6L instead, a lot of problems melt away.

As it accepts a triple-A or lithium battery box, it basically is built for buwizz. The only question is whether the cables reach all the way to the back if you don't have an IR receiver in the middle, but that's just a question of adding an extension lead or three. How would it look with the Corvette mudguards? Appreciate they don't exist in white, but just for sizing.

If you don't already have "brick controller 2" app, you should get it. It will allow you to freely program any output on any Bluetooth hub, to react how you want with a playstation or similar game pad. It's so easy and makes your vehicles so much easier and more playable, that I don't think it's worth the trouble of trying to stay pure and use the Lego app and touch screen or try to make a digital button remote work, which would be a disappointing way to control an anaolg system.

But I'm sure using other people's IP to sell a product here is different to all the Chinese bootleg Lego and moc stealing companies. *Definitely* not the same thing at all. Right?

Is any caution needed here in terms of using the makers' logos? I think so.

The one which just failed on me is in a Buwizz model. You can use every position one at a t time on one side, but on the other side as you reach a certain point it shoots to the end stop and stays there. It'll come back if you command it to the opposite (good) side. The previous one failed the exact same way.

@Zerobricks I know buwizz is developing a buggy motor, but it would be amazing if they develop a servo too. There's a lot of room for improvement from TLG's attempt in terms of power, accuracy, and reliability. People already pay 30e for TLG servos knowing they're no good but there's no alternative. So the market definitely exists. Maybe it's a use for the mysterious port on top of the thing?

Not cool, Lego. Not cool. Still, at least their customer service is good. One is already in the post to me. I've emailed them now to request another. Are there any better options? Chinese clone/copy servos are all junk. The motors are stronger but they have to go to full 90° before they return to zero which is obviously no fun to use. I'm even starting to think about RC servos.

I had one go the same way, emailed Lego and there's one currently on its way to me. Now today a second one failed the same exact way! Seems like a design failure :(

I've just been playing with greyhound and I've had another servo go faulty. It's doing exactly the same thing, won't return to centre but only from one side. The first was in use on a MouldKing Bluetooth battery, this one's on a buwizz. They've got nothing in common apart from belonging to me and being supplied brand new in the bag by the same seller (brickcomplete). Just bad luck??

Sorry, my edit crossed over with your post. Yes, agreed. They'd be strong enough for sure, but they will of course wear at the pins faster than the steel bodied ones. However any wear may be slow to the point that you never notice it. The AliExpress joints wear fast partly because of the materials but partly because of just how janky they are. Considering the small price difference, I recommend not taking a chance on the alu bodied joints.

And the battery box? They have different rated fuses.

A quick eBay search also found these: https://www.ebay.co.uk/itm/Durable-Metal-Aluminum-Alloy-Silver-Joint-Propeller-Shaft-For-Lego-MOC-61903/303321237598?_trkparms=aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20131003132420%26meid%3Dd8674e24c5c74b52b37eb6e55670e4cc%26pid%3D100005%26rk%3D3%26rkt%3D12%26mehot%3Dco%26sd%3D114240368888%26itm%3D303321237598%26pmt%3D1%26noa%3D0%26pg%3D2047675%26algv%3DSimplAMLv5PairwiseWebWithBBEV1Filter&_trksid=p2047675.c100005.m1851 They say they have an aluminium body, and looks like they're not the same as either of the other two metal options I've listed. Might be worth a try, however the price isn't much less than the DarkIceDesigns joints, and you'd still have the issue of steel pins running in alloy bodies. And you'd have to wait for these from China.

Universal joints can be a weak point on crawlers or other RC off-road vehicles where a lot of torque needs to get to the wheel. The old style CV joints aren't much stronger, and worse they are quite severely limiting in terms of working angle. This can be alleviated by using portal hubs with a reduction or the new planetary hubs, but you may not have those parts or they may not be suitable for your application. If you have this problem, you might have wondered what can be done to strengthen a 3L universal joint. You can wrap bands or string around the connections to strengthen them: This will help to a degree as they won't snap so easily where the one in the first image has, but then you're just looking for the next weak link, and in this case it's the yokes which will spread and spit out the disc never to be seen again. You might like to try the new CV joints without using a planetary hub reduction. They're definitely stronger... ...but they are still a wear part. There are some aluminium universal joints listed on AliExpress. Unfortunately these are pretty janky. They are made of very thin aluminium (they say, but I'm not sure, maybe even cast zinc? ) and the tolerances are appalling. They are very loose on an axle, more so than an old CV joint. Right from new they have about 1/16th turn of free-play in them and in use, the steel pins will wear away at the softer bodies creating more and more play, until at around 1/8th turn of play the yokes can touch each other on each rotation. At that point, they don't have long left to live. Or you can try these better metal joints from Dark Ice Designs. These are not currently listed on the website but they do have more listed on their eBay store. Pictured here compared with CaDa plastic and Chineseium metal U-joints (Yes I am aware that there are only 2x original Lego pieces in this picture, hopefully even the purest purists among us can get past that): They are basically 4mm steel-bodied RC universal joints chucked up in a lathe, and bored (very cleanly I might add) to 4.8mm. You then use a grub screw to clamp the axle in place, there's no cross-shaped hole here. There is so little free-play in these, it's basically zero. Certainly, they have less slop than a plastic joint has. There are some limitations: They are just the right overall length, but they are thicker, this may affect fitment in some models. You can't quite get 1L of axle into the joint without it limiting the working angle, which may affect fitment in some models. They should just about take the short end of a 5.5L axle (particularly the newer ones with the slightly shorter stubs) cleanly. You can use them with plastic axles, but the axles will be scrap afterwards because they'll have a grub screw indentation in them. You can also order metal axles from Dark Ice. They list them in odd lengths only but can offer in other lengths against a custom machining fee. Be aware the metal axles have a 1mm rounding added to each end to be gentler to plastic pieces, this again may affect fitment in some models. Even if they're not pure, and even with their fitment considerations... I think this piece solves the problem of broken universal joints once and for all.