Krxlion

I have an unusual question for you @Daniel-99 about gear ratio in your MOC and in general solutions. If I can see correctly you have: - 5:1 gear ratio in 3d-printed planetary tranmission - 1.4:1 gear ratio in 28-tooth gear to 20-tooth gear (those gears are to move force to main driveshaft) - again 1:1.4 gear ratio due to differential usage - 5.4:1 in planetary hubs - AND If you put your gearbox into first gear it will add another 5:1 Those all transmissions puts model in situation where you can approximatelly have 96.428:1 gear ratio(first gear) or 17.857:1 gear ratio(second gear), which is pretty huge gear ratio for first gear. Are you not having issues with that? For example If you drive on first gear at full speed on normal road and then suddenly realese the throttle, the force in the driveshaft cannot go anyway, because of such big gear ratio, or am I wrong? Can you move the car freely on first gear with your hand on a ground like kids toy, without any power? If you cannot understand what I am saying it's okay, I could have overcomplicated it, haha :D I am struggling myself with similar topic and I cannot just gear down the motor speed infinitely, because If I do that too much, the car will each time I release throttle bend the axles and bricks in general.

Good to hear that! I was thinking myself to update TROPHIC topic as I heavily modified my MOC. I was experimenting with three different BL motors but each have its own upsides and downsides. Main goal was to actually build up torque in a smallest possible area (something like you use with 3d-printed components on A2212 BL motor). We will see how it goes, tomorrow I will probably run some tests.

I have watched your video recently and I love this MOC. Clean cable management, robust design, clever suspension and driveshaft, good steering angle. On top of that I envy this two-speed gearbox, I would like to try this solution myself, but I feel like I would need a lot of 3d-printed parts, haha :D Keep up the great work and I am looking forward for your MOCs releases. :)

This topic was raised due to our recent discussion with @Daniel-99 and @FriedlS, thus can be used to discuss ways of implementing brushless motors to our lego technic creations. We may also speak about other modifications that surely comes with implementing brushless motors like transmitters, receivers, ESCs, ball bearings, printed parts, etc. To start of, I want to get everyone a picture what we need to power our models with brushless motors: Brushless motor - for example A2212 1000KV 2-3s (A2212 - meaning model type and dimensions, 1000KV - how many turns does motor make when we power it with 1 volt , 2-3s - which type of battery does motor support). Transmitter - for example DumboRC X6FG (good starting transmitter that often comes with suitable receiver, which supports gyro function - it helps the model go in straight line using countersteering). Receiver - like mentioned above. ESC - heart of brushless setup. Think of it as lego technic hub that you connect all motors and receiver to it. The ESC must be bidirectional, usually for mentioned above motor 30-35A should be enough. You may go with SurpassHobby 35A ESC. Servomotor - GeekServo, simple, does it job and is easy to implement in lego models due to pin holes in it. Battery - usually we can choose between 2s and 3s. Second option is more powerful but often simply bigger. My choose was GensAce LiPo 1800mAh 3s 11.1V 45C, but I find it now too big. Battery charger - for example iMAXrc B3. It is cheap and simply does the job, but you can get a better one, suited exactly to your battery capacity and number of cells. If you have any doubts what to choose or how to start, feel free to ask, that is especially the case why this topic was raised. There are some things that you need pay attention one, like matching connection plugs of your ESC and battery, how to transfer RPMs from motor's shaft to lego gears, how do you plan to hold your motor in lego model (usually screw the motor to the liftarm using M2 or M3 bolts). Just to not leave this topic without any questions or discussion I want to ask mentioned above guys few more things: 1. @FriedlS you mentioned one of previous posts that you are using carbon axles, may I ask where do they come from? 2. @Daniel-99 are those housing of A2212 brushless motors are available as printable files so I can try to print them on my own? 3. Do you guys know what other cool brushless motors we may use in our setups? 4. @FriedlS do you know the dimensions of those ball bearings that you've been using in your recent model? Maybe we can fit them in technic liftarms or frames if we would additionally drill slightly bigger holes in them?

Very great build Daniel! I can see that you put your heart into this model and it payed out! Amazing performance, car is full of features, drives well and is able to go off-road as well. There are some things that I do not understand, but they are due to fact that I do not know about usage of your 3rd party solutions into this model, but it is okay. I would like to understand how you achieve gear switch option using I believe geek-servo motor and what rc lights are you using as I would like to get my hands on them as well :). Body of your car is a step up level from your previous MOC, maybe only the front lights could be done differently as they seem little bit out of shape. Cable management is done good, someone could tell that this is regular lego car :) I believe I have ordered similar wheels to yours but with 102mm diameter, how do they perform, aren't they too soft for SUV? Anyway, great build once again and I do not know with what else you can get me surprised with. Crossing my fingers for your next releases, take care!

Hi guys, I just wanted to share with you the concept of using A2212 Brushless motor to drive front and back axles at the same time. Link to GALLERY of few photos, so you can see the whole concept and understand what I will further say. In this case the two yellow 2L axle connectors are driven by this single A2212 BL motor. This is done due to slight move of the shaft to the back. I needed to glue them in place though and slightly sand one of them down, so they now fit exactly to Lego stud diameters perfectly (7 stud long whole setup from one yellow axle connector to another). I must say though that I am bit disapointed by the perfomance. In my previous MOC - Trophic, I was using different BL motor and it could handle two driven axles no problem on full load. In case of this setup, first I tested it without gearing (by planetary hub you see above) and it couldn't rotate ONLY front wheels and without load on them. After that I attached the gear reduction you see (planetary hub) and tested it on front axle. The result was okay, output speed is not compared to "Trophic" MOC though, if I would guess. What I wanted to achieve is a small motor setup, working already on both axles and without need of further reductions (except those in differentials) but this concept fails me on that. I will keep you guys posted and If you have any suggestions or simply want to share something regardin our topic, please feel free.

Now this is what I am talking about! Great stuff Daniel! I really like the way you are aiming your models to have around 15km/h max speed which is honestly enough. I have found btw. one cool way to make our A2212 Brushless motors drive front and back axles at the same time without gearing. I might show it up in the weekend. I also really like the idea of driveable front axle with positive caster. This is something I am currently trying to achieve and I am looking for ideas. :) I do not know what yet what king-pin solution put into our models but I might get into it deeper. Ackerman geometry looks sick, the steering angle looks so great that I cannot even believe you manage to do front axle driveable. Your plastic bottle solution gets better, it is more clean, though I still I am not a fan of but hey as long as it does it job it is okay. One thing that In my mind could be done better is body and maybe cable management, but those are really not the things you should concern about. Great stuff and keep us posted on further projects or modification of the current model!

I already saw your video and was waiting for some more details to be shown and here they are! Great placement of the motor and it suits baja buggy models a lot! I like usage of sturdiest, new differential gears in both axles, are those from aliexpress or Lego? I would just cover the working gears using Technic panels, it shouldn't be that hard.

Hi everyone! I want to present you my proposal of a trophy truck. Main goal was to create a big model as capable in speed and climbing ability as it is possible. When main feature of the car was implemented I wanted to attach the body to it as simple as I could so I can reduce the weight effectively. My model features: - 1x 2838 4500KV Brushless waterproof motor for propulsion - 1x Geek-Servo for steering - Planetary wheel hubs - Open 36-tooth differentials on both axles - Brushless motor is connected to main drive shaft with 3:1 gear ratio - Live rear axle - Independed front suspension - Reinforced steering joints - Metal U-joints - Closed bottom of the car - Openable front hood Mass: 1603g (1178g without the body) Regarding brushless setup I used features(apart from what I mentioned above) those elements: - DumboRC X6FG as transmitter and receiver - Waterproof 35 ESC from SurpassHobby - GensAce LiPo 1800mah 11.1V 45C - White lithium grease from Lucas Oil(lubricating gears and each hole where axles turn) Feel free to ask anything. I probably didn't cover everything about this model in this topic so it might be updated in the future. The model was run on the video with about 20-30% of full power, except few moments at the end, where it was approximatelly 60%. I might some day test it at full speed but let the model live for a while, haha. I want to thank those people which inspired me with their work to build my model: @Zerobricks @gyenesvi @Daniel-99 And here are some photos of the car and link to whole album - GALLERY

Simple, yet effective and I assume fun to play :) I would be worried though that some of the parts might pop out and be left on the bottom of water, haha. By the way, what about your iWD4 project is it still in development as I didn't see you uploading any longer video about it.

Same thing, but I am using C+ L motor, which serve as a servo-motor. Something is seriously off, I believe that any C+ motor with center steering module will not work. I wanted to test current limits but I cannot do so If my steering is not working properly. I switched back to Brick Controller app with PS4 pad, everything works corretly.

Those are indeed great news @Zerobricks! I have never before attended beta versions of Buwizz app before, is it gonna be a separate app or simply some kind of checkbox to mark in present program?

Hi there, Daniel! Yes! The receiver has gyro function and it has been turned on, but it has not been securly attached into the body(it holds by Lego rubber band) and it slightly wobles when I speed I believe. During runs the gyro function was on, but set like to 20% of max value and I believe it didn't had much impact into steering performance If any. I ran into several problems in the meantime: - Planetary hubs (and I believe all lego hubs) have slight issue with wobbling. - Car do not run straight in high speed. I could try using positive-caster on the front (I built car with this function before) but I am worrying about implementing another set of 92911+92910 bricks(or other option) to change angle of driveshaft in the front. I will probably first try to securly attach receiver to help me stabilise the car during speeding. Then If that will not work, I will probably try to built much less wobbly hubs out of bricks(I've seen few idead on the Internet). Lastly I can try custom hubs, etc. but this will be final option, though it is curious for me how they perform. :)

After some minor MOC tweaking I have prepared myself for measuring the top speed of TROPHIC. I found a straight line, placed two small glass bottles in exact 10 meters separation and runned model through them several times. I then calculated frames in editing program and came with the results: The body mount is now fixed and the model can climb steep objects such as big curbs. Regarding second part of your answer, I do not believe there are bigger Lego Technic wheels than 107x44 that will suite this kind of MOC. Fixed! Correct! I've also the Lego version of those wheels but somehow I like the grey option on this model. If you would like to get them cheap, you may buy CADA C61008W set. ;)

I am not so great with gearboxes, but If it comes to using them I always reach out to Sariel's videos. In example below he has gearbox that you can attach to another, similar one: You can always look for other films on his YT, he could have something that you can use. :)

Yes, exactly the word I was looking for. :) I put few more photos of the front from side view, so If you want you can see the approach angle. Yup, it could be done the way you say, Daniel. But after all I believe that currently I will focus on fixing mounting points of front section of the body and modify slightly body itself. Great explanation, I don't want though to use this much of non-brick things in my models(custom hubs and liftarms with bearings are still ok, but the plastic cover from a bottle is not something that I would use in my model ;)). The main goal was to simply power the car using the brushless setup and rest should be solved with technic bricks(although I know they have their limits). I might test different solutions like using hubs without gear reduction or portal hubs, we will see in the future. :) The top speed is still unknown, but I would like to check it for my own curiosity and for that I might do a setup like this: - Find straight road without much traffic - Place camera where it can cover wide angle of the road - Place two objects(for example bottles) in 10 meters separation - Run the model in full speed between those two objects - Calculate estimated speed (record with 60fps for as much frames as I can, count the frames between entry and ending points - those two placed objects. Finally, do the math :D)

The problem is not with ground clearance but with body starting too much in front of the front wheels(I do not know how to put in words differently), my MOC have 107mm diameter wheels and it is AWD. I do not understand the part, where you say that rear axle would limit the amount of height. Can you be more precise?

The second thing. Currently I have mounting points of my body slightly in front of a car which decrease full potential of climbility of the car.

Yup Daniel, cover of all gears that are running in the car is necesarry, due that the bottom of the car is covered in all kind of plates and liftarms. I have runned model 3 times and didn't yet need to strip it apart and clean it to get dirt out of, which is great! Are those planetary hubs that you are talking are available on chinese website(If you know what I mean)? :D I currently run original Lego ones but If they will break I will be more than upset, haha. I would love to upgrade the model, I am more of a person that upgrades the model, instead of stripping it and going to another. Currently I have few issues: - Turn radius is not so great - Bad fit of BL motor in the car(the motor is slightly bigger than three lego studs - 28mm diameter, where ideally it should be 24mm) - Modify body - I cannot climb steep obstacles, because of the size of the body structure I have no knowledge regarding metal bearings (no bearings I know will fit lego liftarms, you will need to heavilly modify it or buy whole liftarm with bearing). Regarding moving from planetary hubs to metal ones, I believe that soon after the change of original plastic hubs I will start breaking 52730+52731 parts in the front axle. I might though be mistaken because I've never used previously metal hubs. All in all, I was afraid of using 2838 4500KV motor in the setup but I believe with some pruedence and starting reduction(for example 3:1) you may run it in your models.

I have added more photos into the gallery, please take a look. :) I reinforced steering joints so they will not pop out during high speed on bumpy road - there is 61184 brick inside pin hole, where ball pin is insterted. Apart from that, most of front axle comes from one of @gyenesvi MOCs (he has available instructions on rebrickable), I adapted it to my MOC, reinforced steering mechanism and found a way to insert a geek-servo instead of PU L motor No issues at all with planetary hubs, they hold very well! Although, I must mention that previous version of the MOC had 52730+77590 in the rear part of driveshaft and 52730 broke down(those small plastic grooves where you insert 77590 brick), so I ended up with switching to 92911+92910 setup and inside is metal U-joint. Model weights 1603g (1178g without the body).

You can also take a look at this guy: http://www.youtube.com/watch?v=qgf4Vfnd5Hg&t He found brushless motor that fit exactly in Lego PF M motor, you may also find brushless motors in same size but with more torque instead of speed. :)

Currently my model has THIS way of transfering power from the motor to lego model. I find it more "clean", I do not like mixing my bricks with superglue or anything of that sort, haha. You may take a look at other videos of this person channel, they are quite usefull for brushless enthusiasts like us.

I love it! I believe you would need to drill bigger hole to fit it for example in liftarm. The problem is that liftarms are around 7.38mm high which is not enough, you would simply cut the piece in two. I also wanted to mention one thing about lubrication. I received today a package with white lithium grease and after some initial tests I must say I find it better than silicone grease which I used to this moment. With new lubricant I can move more easily main drive shaft and what is more important it sticks better to the gears and does not splash away that easily during high RPMs.

Many thanks Daniel! I must say your list regarding gears problems is interesting, I will keep it in mind. I started lubricating lego gears but due to high rpm of my current brushless motor the lubricant simply go away few seconds after revving the engine. :D I have watched the video with some subtitles and ordered right away the A2212 1000KV just to have it in stock for future MOCs or to replace the current one :) The casing showed in the video is marvelous, I believe it would not have a problem with escaping lubricant like I have due to closed case. All in all I am aiming at something that @FriedlS created, baja truck but in a bigger scale, something 1:10 or 1:12, 10-15km/h speed and decent climbing ability (35-45 degree angle). Maybe if you are interested I could film my current model and upload it in a new post, so you could help me with solving my issues. In the end I want to use as less as possible non-lego parts. My initial thoughts was to create a MOC that is simply delivered with more power. I bought two BW 3.0 in the past 1-2 years but even implementing those two in a single model is not enough if you use BW Motors or Buggy motors, shutdown, bluetooth lag, etc.

Hi guys, For the last few months I've been trying to implement brushless motors into our bricks. I have a few questions and if you would answer them I will appreciate that a lot! :) 1. I am struggling with melting axles, this is probably because of high RPM motor. I am using 2838 bl motor, 4500kv right now and if I would choose different one, do you recommend A2212 1000KV for lets say 1-1,5kg models or should I go with different one? 2. What pinion gear are you using to match lego gears? I am using 10T Bullet Flux Pinion but I find it just slightly to small, it rotates with for example 20T lego gear and there is small space between those two gears. Just to sum it up, I am using DumboRC 6r with gyro receiver, I have 35A ESC and one geek-servo. Currently I am working on baja truck, actually I have one now but during some recent tests I still believe this model is not yet ready to be showed on forum. :) PS Daniel, your model is great I am looking always forward to see more of your models since you release Dragonfly! :)