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Found 18 results

  1. Hi everyone! Not so long ago, I presented a WIP project I was working on, a 2WD Drift car. So the question is, why am I showing you this model. Actually, the best answer would be that I gave up too fast on the previous one and immediately move to the smaller scale. During building this model, I came to the realization that the problem with drifting in the previous car was not with tires (although suited drift wheels are much better), but with the floor I was testing it on. From that moment on, I was testing the model in a different place, where the floor is made out of wooden panels. Features Locked 4WD with different speeds on axles(front 1:1, rear 1:1666) Positive caster angle Working front and rear lights suited for Lego Regular Lego 49.5 mm wheels (15413+56145) Opening trunk Powered by RC setup (with gyro function - helps counter-steer) Design After the first failed attempt to build a drift car fully out of Lego bricks, I still wanted to use rubber tires and achieve my goals. In the time I was starting to build the model, there were at least two similar cars posted, which reminded me about @Anto Hoonicorn MOC. I wanted to preserve his idea of front axle in my MOC and enhance my model by giving its rear axle faster rotation speed, thus making it slip faster. The source of power still remained in A2212 BL motor, in the drivetrain you can see that it was geared down by planetary wheel hub. Model is steered by geek-servo directly connected to the axle, which controls the steering rack. Legend (explanation on stud.io bricks presented in the picture above) 4x yellow stacked 28-tooth gears are in fact a A2212 motor Grey bricks shaped in 5x3x3 are in fact a geek-servo More renders and pictures below Non-Lego parts usage RC setup (DumboRC X6FG, 35 ESC SurpassHobby, SOARIN2 S 1300mAh 7.4V 30C, A2212 1000kv brushless motor, geek-servo, Lucas Oil for lubrication) 1x metal U-joint 4x 1x3 trans-red plates from CADA Finally, I got a short video presenting the model Mass 770g Dimensions 30 x 15.2 x 12.1 cm Scale 1:12.5 GALLERY
  2. Hello and welcome in 2024! Today after quite a break (due to moving to a new house) I present you... Well, it does not have a name yet. Although it is kinda based on real car - Ford Probe II (which I own myself). The idea was to create a version of mentioned real car, but with rear wheels drive so it would be able to drift. After some time spent in the building process I convinced myself that I will simply go with the flow regarding body and just slightly base on Ford Probe II. Features Locked 2WD (rear wheels) Double-wishbone suspension Camber (provide less tire contact with the surface and helps drifting) V6 fake engine Regular Lego 56mm wheels (56908+41897) Manual pop-up headlights Powered by RC setup (with gyro function - helps counter-steer) Design The initial idea was to create a car in roughly 1:12 / 1:10 scale that is able to drift with rubber tires. To help achieving this I immediately knew that I need a camber in the car (this section was heavily inspired by plastic gear YT channel). For differential I went with an old 28-tooth one, because this is the only one (I believe) that can be locked. I also wanted to finally have fake V6 engine in my MOC, so by placing another 20-tooth gear in the back of the frame it not only helped transfer rotation to V6 section, but also secured differential, so it cannot skip gears. Source of power comes from A2212 BL motor, it is then transfered to Lego system using slight modification in its shaft (I explained this topic a little bit in one of my previous posts. If you want me to elaborate it deeply, please let me know :). I then gained torque but decreased speed using 46490 wheel hub as transmission. The steering is done by geek-servo, although I have a problem with those, because in fact they are not fully rotating +90/-90 degree, so I needed to put 20-tooth gear first and follow it by 12-tooth so it rotates slightly more than +/- 90 degrees. This solution provides a massive steering angle, which cost me giving up on regular wheel panel arches. So does it drift, that is the question. Answer is yes and no, what I mean by that is that without a body it does have a perfect 50/50 front/rear balance and tuning the gyro helps even further with drifting. I recently started to work on a body and sometimes I do test-drives and I can see heavy impact of that extra bricks. With the body now placed mainly in the front of the car it is a lot harder to handle and it mostly spins like most of lego "drift" cars. We will need to wait for final results after I finish the whole body and tweak everything. The video will be for sure, but not yet (need to learn properly how to drive it and build body ). Time for some renders and pictures Legend (explanation on stud.io bricks presented in the topic) 4x yellow stacked 28-tooth gears are in fact a A2212 motor Red bricks shaped in 5x3x3 are in fact a geek-servo Gloss 11x3 panels with some other bricks that are in two 5x7 technic frames are in fact a battery Front axle close-up Rear axle close-up Built MOC Partly finished body Non-Lego parts usage RC setup (DumboRC X6FG, 35 ESC SurpassHobby, GensAce LiPo 1800mah 11.1V, A2212 1000kv brushless motor, geek-servo, Lucas Oil for lubrication) 2x 3L axle cut to 2,5L (used in driveshaft in each wheel, because of non-standard length) 2x half bush cut in half, so it is 0.25 stud long (used in driveshaft in each wheel, because of non-standard length) 2x metal U-joints Mass (without body) 706g Dimensions (without body) 21.3 x 33.6 x 8.5 cm Scale around 1:11 Gallery
  3. Hello, EuroBrickers! I am pleased to present to you the second version of my RC Lego Trophy Truck EAGLE. To be more specific, this is the third deep modification of the second chassis. Not surprising, as I've been working on this project for over three months now. For a better understanding of this topic it is worth reading about the first version. A better quality photos could be found on my BrickSafe. And a video: First looks: Features Independed suspension at the front with positive caster angle. 4-link solid axle suspension at the rear with anti-roll bar RC shocks (80 mm at the front and 110 mm at the rear) Brushless motor A2212 1200 kv for propulsion, Geek Servo for steering, 1500 mAh 3S Li-Po for power Strong and efficient transmission with metal U-joints and metal bearings. 95 mm RC wheels Light-weight bodywork Main goals "It's never a good idea to stop if you have something to improve." With these thoughts I was preparing a post about my Eagle a month ago. Here's a list of things I wanted to improve: Weight distribution: the heavy electronic components located in the cab loaded the front suspension more than the rear suspension. Rear axle geometry: due to triangulation on the rear axle, the driveshaft and lower suspension arms were located very high off the bottom of the truck, which limited the maximum compression angle of the rear suspension, and the entire chassis was not set to the horizon. Rear suspension setup: a true trophy truck requires a suspension with progressive stiffness. Front axle: steering was very sensitive, rather unusual front triangle shape and tilted lower suspension arms. Overall bulkiness of the chassis. Electronics The Eagle V2 utilizes the same electronic components as the Eagle V1. The story of my choice of such components is given in the post about Eagle V1. Therefore, I will be brief here. Motor: A2212 1200 kv Battery: 3S Li-Po 65C (30C is more than enough) 1500 mAh Controller: 2-3S 35A Transmitter: FlySky FS-GT5 Pros: Brushless motors last longer than brushed motors. High speed and torque in a compact size (about 3 BM in an XL motor) Radio control (best for fast RC cars) Cheap components (compared to Lego electronic components) available at local RC stores. External Li-Po battery allows for different layouts and unlimited power flow. Cons: Requires advanced techniques to build strong transmissions (requires lubrication) Otherwise can easily damage plastic parts. Not an easy decision for purists. Difficult to share instructions with others. Have to take care of tangling wires (same goes for large Lego-is designs). Non-universal solution, suitable mainly for RC Lego machines without a list of additional features. Frame & layout The Eagle V2 has a new "tube frame" (or chassis). This is why I decided not to call it a modification of my Eagle. Let's take a look at it from front to back. All important terms in this section are marked with bold text. In addition, this terms are highlighted on pictures. The front triangle uses the same "almost right" triangle with 14,15 and 6 stud lengths as the Eagle V1. The lower tube of the front triangle is made of two flip-flop beams that have been stacked together. This solution provides a sufficient level of stiffness and resistance to torsion. In addition, I was able to bring the suspension arm mounting points as close to the center as possible. The lower tube of the front triangle is adjacent to the flat bottom made of panels. The upper tubes of the front triangle intersect with the front wall. Further they pass into the side tubes of the cockpit. These tubes are made with flip-flop beams, which allowed me to secure them in place with a 15L front cross-brace (the Eagle V1 cockpit was 2 studs thinner). It's worth noting that the GeekServo motor squeezed perfectly between the lower front triangle tube and the cross-brace of the front wall. Thus, it practically reinforces the front triangle. The cockpit ends at the rear wall, which is reinforced by a rear triangle and structure around the transfer case housing. The side tubes pass into the rear H-tubes (horizontal). At the same time, the rectangular rear triangle is mirrored to form another rectangular triangle at the very back of the truck. The cross-brace on the rear wall is made using L-beams and 3D printed motor housing. Now let me describe the layout of the electronic components. Using a custom transfer case housing, I was able to move the brushless motor out of the cab. It is now located directly behind the rear wall. More importantly, I was able to move the Li-Po battery out of the cab. It is now located above the motor. It is true that this solution increases the center of gravity, but on the other hand it provides excellent weight distribution, which is very important for a trophy truck. The controller is located in the cab next to the driver's seat. Both battery and controller have no pin-holes, but I was able to fix them in place quite greatly. To load the rear axle even further, I added the spare wheel. Bodywork My main goals with bodywork of Eagle V2 were the following: keep it light keep the original shapes of Eagle V1 improve the proportions As a result I made the whole truck one stud longer and two studs wider than the first version. Now cockpit is wide enough to fit the driver`s seat. Also I changed the bonnet and the front grill. Finally I changed the very back of the truck to make it closer to real prototypes. I have to add, that not only the bodywork make the car look good. More importantly to keep the proportions in the chassis. The authentic look of the Eagle V2 is achieved with the proper settings of the suspension. Transmission I'd like to make a 3D model of my truck and show you a nice rendering of the drivetrain, like some great technical builders do. However, the Eagle V2 has a lot of custom parts and a bunch of "illegal" techniques like "almost rectangular" triangles. So I will just mark out the transmission components: Brushless motor with custom housing with planetary gear inside (1:4 gear ratio) Central transfer case with 28:20 gear ratio Rear differential with 12:28 gear ratio The transmission is built on carbon fiber axles and metal U-joints. It is separated from the frame by metal bearings. Metal bearings are used in the center transfer case, in the 5x7 frame that holds the differential, and in all the wheel hubs. I also lubed the planetary gear inside the engine case. Suspension geometry As I've said before, trophy trucks are all about suspension. So the main reason I did a V2 of my Eagle is to try and improve the suspension (both front and rear). Front suspension: Truth be told, not all custom parts turn out to be universal. On the contrary, the idea of efficiency in certain places and the idea of universality are not compatible at all. The Eagle V1 front wheel hubs are a prime example of this principle. They were originally designed for IFS street cars with smaller wheels. Therefore the basic ideas are present in their geometry: An inverted ball joint for the lower suspension arm (which is great in general). Combined with the tilted front suspension, they looked nothing like real trucks. The steering arms were 0.5 studs long, which resulted in very sensitive steering. I also didn't really like the 8 stud length suspension arms, which required custom of steering links to work properly. So I designed a new front suspension system that includes: 9 stud length suspension arms. New hubs (originally designed for live-axles) with 1 stud length steering arms. Thus hub does not use the ball joints! The new design is a deep modification of the Falcon trophy truck front suspension, which has proven to be reliable. In the V1, I used 8-studs suspension arms to fit within a certain chassis width and maintain a strong lower tube of the front triangle. However, by using stacked flip-flop beams, I was able to keep it 1 stud wide without losing stiffness. Rear suspension: It won't surprise you that the Eagle V2 has a new rear suspension. Here's a list of the changes: A new rear axle has been designed (again with a different set of custom hubs). It's more compact than the one the V1 had. The upper triangle of the suspension arms has been inverted (to match the real-world examples). New lower arms have been build. Now the live-axle was given the necessary degree of freedom. The attachment points for the suspension arms were lowered by two studs. This modification was possible due to the changes in the drivetrain described above. The anti-roll bar has been redesigned to match real prototypes. It resists to the twisting effect of the rear axle that appear in the acceleration. Shocks "Once a perfect suspension geometry is achieved, one may look for a proper set of shocks springs" The best springs Lego ever made are the hard 9.5 L springs, because they have a good amount of travel and responsiveness. For example, the 9.5 L soft shocks are not as good because the spring force has a hard time overcoming internal friction. On contrary, the 7L hard shocks have little travel and not enough stiffness to work properly with the hard springs. So I used 9.5L hard springs in the Eagle V1 and early versions of the second chassis. I tried to build a progressive rear suspension using Lego springs, but was not successful. The resulting design was either too unreliable or too bulky. I guess I lacked luck and skill, but I couldn't build a suspension that was both soft and shock resistant. It was either too stiff to absorb big bumps or too soft. So I decided to use RC shock absorbers to properly address this issue. RC shock absorbers have different springs that allow you to adjust SAG and progression without having to move the shock absorber mounting point along the suspension arm. I once tried to adapt RC shock absorbers to Lego, but couldn't find a suitable way to attach them to the Lego pins. Fortunately, a working solution was offered by Ryokeen in his Generic Brushless Trophy Truck. I again had to modify the chassis to fit 1:10 scale RC shock absorbers. Front suspension has 80 mm shocks with 2.5 studs travel. I mounted it behind the suspension arms as it is done it real Trophy Trucks and many RC scale models. There was a way to place it through the upper A-arm, but such solution required 4L liftarms. In addition it had not freedom in the choice of mounting points. Rear suspension uses 110 mm shocks with approximately 3 studs of travel. Additionally they have a dual spring setup, which give the desirable progressive hardness to the rear suspension. Again, I tried to mount rear shocks in the same way it is done in real Trophy Trucks. Developers diary. 3-7 Sep An Eagle V1 was finished. The driving tests started. Front wheel hubs are the same as in Hornet 4x4 Buggy. 11-15 Sep The new front triangle has been built. Now truck has a tilted lower tube and positive caster. The differential has been changed from yellow to red one. 17 Oct I stated developing a new chassis with a different set of ideas behind. (mostly with the triangulation in the rear axle removed and central transfer case added). 24 Oct First prototype of the new chassis has been built. In addition to the redesigned rear axle, I made a new front axle with a shock coming through the upper A-pillar. 27 Oct I started building a bodywork for a new chassis. 1 Nov The first modification of the second version of Eagle has been finished. I started the driving tests. The rear suspension has a new idea if mixing anti-roll bar with additional shocks to achieve progressive suspension hardness.... that was a total madness... 8 Nov The whole chassis has been widened by 2 studs for better proportions. 14 Nov A new rear suspension ideas has been applied. The back of the Truck has been changed. Now the rear suspension has two sets of hard 9.5L springs on each side. Progressive stiffness... Bulky realisation. 25-28 Nov RC shocks has been added. For that reason both front and triangles has been redesigned.
  4. Hey, guys! After a 3-month brake from Lego, I am glad to show you my new RC trophy truck, called Eagle. I apologise for the quality of photos and I will try to improve them later after I will get myself a studio light. I will also make a proper introductory video when I will get enough outdoor footage. Features Responsive long-travel suspension with 4-link live-axle at the rear and double wishbone at the front Brushless motor A2212 1200 kv for propulsion, Geek Servo for steering, 1500 mAh 3S Li-Po for power Strong and efficient transmission with metal U-joints and metal bearings. Great ground clearance for outdoor use, 95 mm RC wheels Light-weight bodywork Experience and Inspiration I guess that nobody will be surprised If I would make a confession that I have a deep passion for Trophy trucks. This type of vehicle suits the best for the role of a fast RC Lego cars which are build for outdoors. Indeed, outdoor environment is always rough and "bumpy" for Lego cars. I took my inspiration and first experience form several well-known Lego builders, such as: Sariel RM8 ZeroBricks GooberReboot Through the last 3 years of intensive engineering I made a few attempts in building myself a "proper" trophy truck. Each of them had it`s own features and technical problems: Heavy-duty Trophy Truck: RWD, 2x BM, 2x Buwizz 3.0 units, 95mm wheels. Problems: "big scale" which caused a serious load for motors, over-tilted front caster. Phantom: RWD, 2x BM, Leshy control unit, 85mm wheels, mid scale. Problems: lack of power from Leshy unit, lack of articulation at the rear, plastic wearing in the wheel hubs. Wilde Beast: 4WD, 4x BM, Wixy RC control + 3S Lipo, 95mm wheels. Problems: "big scale" which caused a serious load for motors, indep. susp. with a questionable geometry. Falcon: 4WD, 4x BM, Wixy RC control + 3S Lipo, 75mm wheels. Problems: indep. susp. with a questionable geometry, overheating of motors at the maximal RPM. About a year ago I switched from Lego Buggy motors to a Brushless motor (for the reasons which will be covered later). This was not an easy switch for me and I had to learn some RC electronics theory and find the proper ways of using brushless motors with Lego. My latest RC cars with Brushless motors was: Unimog trial truck Pathfinder SUV Hornet 4x4 buggy With pathfinder and Unimog projects I studied the 4-link live-axle suspension geometry, while with Hornet project I found the way to achieve a proper suspension and steering geometry with my custom wheel hubs. With this projects completed I get myself all cars I need. - What should I build next? With such question in mind, I faced a deep burnout from Lego, so I decided to take a summer brake. Hot summer days returned me my passion for Lego, and I had a plenty of time to plan a new project. I felt myself ready to make another attempt in building myself a "proper" trophy truck. That is how the story begins. Electronics With my latest truck Falcon I reached the limit of what Buwizz motors could handle. Some time ago there was a discussion about efficiency and power-to-weight ratio. I would not resist that with the growing number of motors and Buwizz units, one could get a better power-to-weight ratio, though such a way faces the problem of plastic-weariness quite soon. With the growth of the number of motors, also grows the size of the car and it`s total weight, which get distributed to the four Lego plastic wheel hubs! I faced the plastic-weariness problem of Lego hubs with my Phantom truck, and solved it by purchasing custom wheel hubs with metal bearings, which I were used in the Falcon truck. Moreover, there was no gearing in the transmission of the Falcon truck: each wheel was connected to it`s own motor via driveshaft with metal bearings. With 4x Buwizz motors on board, powered by strong 3S Li-Po battery, Falcon had a great power-to-weight ratio. Through multiple tests I found that It can not handle full throttle for more than 45 seconds due to the rear motor overheating. It was pretty clear to me that RC Li-Po could easily overfeed 8 or even 12 motors with power, so there was no sense in adding more BM motors. Likely to me, one Russian AFOL developed a 3D-printed housing for Brushless A2212 motor which allowed to use it with Lego. I purchased two sets from him, and mot I have 100% RC setup. There was no problem with the lack of power or motor overheating anymore, but it was a real challenge for me to overcome this energy! Transmission With BM motors it is very natural to distribute the torque among axles \ wheels, by having separate transmissions to each axle \ wheel. But with Brushless motor I had to use "realistic" transmission, since there is only one output with a plenty of speed and torque. Despite the fact this motor is a baby-motor in the world of RC cars, It has enough power to twist Lego axles with instant reaction to the throttle. Custom 3D-printed housing has a 4:1 planetary reduction, but the speed of the output is enough to cause gear-melting. That is why the following decisions were made: use metal U-joints all around, most of them have a 3L lego axle glued from one side to prevent them from falling off. use silicone grease to lubricate the planetary gear in the motor housing and some external gearings. use custom parts with metal bearings to separate the transmission from the car frame. use carbon-fiber axles in the central driveshafts. The new Eagle truck has a very simple RWD transmission with a single "external" 14:23 gearing in the differential. Recall, that the 3D-printed motor housing has a 4:1 gear reduction. So the motor is connected to the differential via carbon-fiber driveshaft. From the differential power translates to the 95 mm RC wheels via half-axles with metal U-joints. The whole transmission sit on the metal bearings (custom wheel hubs with metal bearings, custom 5x7 frame with metal bearings for differential housing, motor output passes through the connector with the metal bearing). Surely you have noticed that I lifted the central differential by one stud over the wheel axle in order to achieve a higher ground clearance! Which differential to use RED or YELLOW? RED differential has a 28:12 reduction which reduces the load from the driveshaft and the motor. Moreover, such gear ratio is more realistic. On the other hand, YELLOW differential has bigger teeth so it is stronger. But more importantly, is that YELLOW differential is 125% more efficient than the RED one, since it has bigger gears and does not scratch the 5x7 frame under the load. In fact, I am using a custom torsen differential with 23-tooth gear. It also does not scratch the 5x7 frame and hold half-axles much stronger than the original YELLOW diff. Suspension Trophy truck is all about suspension, and it was the most challenging part for me! Non of my previous trophy trucks has a proper suspension: it was either rear live-axle without articulation (Phantom, heavy-duty trophy truck) or independed rear suspension (Wilde Beast, Falcon). As I found from multiple driving tests of Phantom, rear axle need an articulation, cause otherwise RWD car loose the speed on bumps. IRS give the desired articulation and stability, moreover it is very simple to build and it has a low unsprung mass. Despite that IRS has a limited articulation and it is not presented in real Trophy Trucks either! Lego engineers designed a ball-joint connection, which is used in many Trophy trucks. It gives a single-lever suspension (with it`s simplicity and stiffness) and desirable articulation. Well, I did not use it, since it has no metal bearings for the U-joint inside the ball. So I had to replicate the 4-link live axle. 12-long reinforced suspension arms, invested upper triangle, 9.5 L springs, attached to the mid of lower suspension arms, Anti row-bar with a carbon-fiber axle, Now let`s move the the front suspension. Surely, real Trophy Truck has a complex front suspension, which is impossible to replicate with lego bricks. Though lego-ish version share important principles with real prototypes: double wishbone with 8L suspension arms (9L was too wide here) Positive caster angle Reinforced lower arms Shock is attached to the lower arm closer to the center of the car Steering rack is located in the front of the car Again I use custom wheel hubs with metal bearings. They have an inverted lower arm mounting point, though it is possible to use Lego hubs instead. With hart 9.5 L springs the front suspension has a long travel, moreover it has a great balance btw softness and responsiveness + side-way support. Bodywork & Frame In order to achieve a positive caster angle I tilted the lower part of the frame. At the same time, the upper part of the frame. At the very front of the car upper and lower parts of the frame meets together which form the "almost right-angle" triangle with lengths: 13+1, 14+1 and 5+1. (right-angle triangle has the following lengths: 12+1, 13+1 and 5+1). Second time I use the Pythagoras theorem to make a force triangle for the rear springs attachment points. I tried to keep the frame of the truck in 13-15 studs wide, to use 15L liftarms for cross braces. I was Luckily to me I was able to squeeze all electronics into cockpit. This give the model 50:50 weight distribution and a "low" (for such high car) gravity center. Well, one would prefer to obtain 35:65 weight distribution for the RWD truck, but It would raise the gravity center and would require extra structure over the rear axle. The whole bodywork consist of 24 panels and a few bricks, so it does not cause much weight to the truck.
  5. Hello Eurobricks! A few months passed since I shared with you my creations. Well, I was working hard on two RC projects and now I am proud to introduce you one of them! It is called "Hornet" and it is an Ultimate 4x4 Baja Buggy. Technical specs: 4-wheel drive, open differentials Full independed suspension Brushless motor, 3S Li-Po, GeekServo Custom wheel hubs with metal bearings Carbon-fiber axes, metal U-joints Transmission sits on the metal bearings Positive caster angle, kingpin inclination, Ackerman Anti-rowbar at the front axel 98 mm RC wheels understeering Light tubular frame A story behind the build. Half a year ago I bought myself a Brushless setup adapted to Lego. It can provide a strong and stabled stream of power to my RC Lego cars. In two days after the motor arrived I build a first project with it to test its capabilities. Of course, this was a buggy! The main goal was achieved, I was able to test the new system and it performed greatly! Though I was not happy with the car itself. It had technical problems with both front and rear suspension, steering, overview and proportions... During the winter holidays I found a great set of RC wheels on AliExpress. They looked ten times better then all the other RC wheels I had, so I bought them and at once started a new 4-wheel drive project (which will be revealed in my next post). All I will say now, it has solid axle suspension and no planetary wheel hubs. So it appeared to be quite fast and somewhat unstable due to the soft suspension and high center of gravity. I decided to postpone that project and build a fast and more stable Baja truck with the front in-depended suspension and the solid rear axle. The fist prototype can be seen of the picture below (half-way dismantled) and it looks totally weird, especially the placement of the Brushless motor! With such layout I tried to load the rear wheels, but did not succeeded. Despite a completely failed project, I get two important ideas from it. 1) My custom wheel hubs allows to build an advanced front suspension and steering with king-pin inclination, positive caster angle and Ackerman geometry. Also I learned how to use a half stud off-set for the attachment points of the lower suspension arm. 2) The placement of the Brushless motor behind the rear axle greatly load the rear wheels. I was not ready to give up, and decided go bigger next time and use my favourite 98 mm RC wheels. By widening the wheel base significantly I decided to solve the front wheel drive problem! It is well-know that steering rack is usually interact with a differential. Also the steering rack must be placed behind the front axle to achieve the Ackerman geometry. So I decided to move the front differential one stud to the front. The first sketch of the front axle looked very promising, so I decided to "copy" it for the rear axle. Well, to keep the same wheel base as at the front i needed to use the half-stud off set once again and this time on both lower and upper suspension arms. That is why the rear differential is covered with a mess of connectors and beams... Solving all problems with axles, I connected them together via central driveshaft and had to decide how I should place the Brushless motor. The problem is that the motor has a size of a PF XL motor, and so it requires a 24 to 24 tooth gear combination to connect it to the central driveshaft (and place the motor on a side or on top of the driveshaft). I was not happy with it because big gears would stick out from the flat bottom of the chassis. The brilliant idea came right in time! I decided to place the motor behind the rear axle and place the another driveshaft over the rear differential. This allowed me to use a 12 to 20 tooth gear combination! In addition it loaded the rear axle to achieve the understeering feature. It took me another day to finish up the first prototype, and I took the Buggy to an extensive driving tests. These tests took me over a month to complete, since they were interrupted with a melting of the snow. The following improvements were made (one by one): Reinforcement of the upper suspension arm. First version of the front suspension was falling apart on each big bump. Lowering of the suspension by one stud. This was made to increase the stability on the straight line and make the overview of the buggy closer to references. Also I widened the tubular frame for the same reason. Playing with gear ratios: differential swap and swap from 12:20 to 16:16 gear combination in between the driveshafts. Adding an Anti-rowbar with a carbon-fiber axe to the front axle. It was added to increase the stability on the fast corners. Making 3.5 L axes to solve the problem of the front U-joints falling off from the differential. The results. A tremendous efforts had been applied to finish this Buggy. A lot of hard work, tricky decisions and big regrets... Does the Hornet worth it? - NO! As a result I build myself a balanced RC car with a precise control, decent speed (about 15 km/h), enduring transmission and good-looking bodywork. But I would not suggest anyone to follow my way, because it will cost you a lot! If you want to get a good driving experience you would better buy an RC car! LOL.
  6. Hi everyone! I want to create an off-road vehicle with these functionalities: - Speed around 13-16km/h - Positive caster angle - Good steering radius - Covering bottom of the car - Vehicle must be as versatile as possible (on-road, off-road, climbing capability) - that is why it is called Frontliner - No melting/damaged axles(or other parts) or at least minimal wear - this is with usage of brushless motor A2212 1000kv - Weight around 1,2 kg - Big wheels 100-110 mm (provide additional ground clearance) - Two-speed gearbox (optional functionality, may be implemented in the future) - Total gear reduction set to approximately 12:1 (including differentials reductions, etc. This still provides good speed of the model with usage of brushless motor) - Pendular suspension (optional functionality, currently implemented and it's very useful) What I will be using (non-lego): - RC setup (DumboRC X6FG - provides gyro stabilization) - Geek-servo motors (those works simply as servo-motor, but with 6 channels of the receiver I might use additional geek-servo motor as switch for gearbox) - A2212 1000kv brushless motor (I was previously using different BL motor, but this one is 14-pole, which means it has shorten rotating angle per-pole and is more precise in working with the throttle than 2838 3200/4500kv BL motor) - Metal universal joints (those are simply more robust than Lego ones) - Lucas oil white lithium grease (used to lubricate gears and axle holes) - 35A ESC - 3s li-po battery This is the first time I am seriously using Bricklink Studio to create a MOC. I had few attempts before, but this time I really pushed myself to at least design front and rear axle in it. Front axle: I used Geek-servo motor to steer the model (the front red weird stack of liftarms is actually it, dimensions 3x3x5). It also features planetary hubs, reinforced steering joints and planetary hubs. Rear axle (heavily insipired on @gyenesvi 42129 C model): We can see here the new differential (knock of part for now. I am soon gonna buy 42157 set to replace it with original Lego one). The yellow UV joint symbolizes metal version of it. Middle section: The yellow stack of gears symbolizes A2212 brushless motor. Between two 5x7 frames I hold battery and on top of that all RC components. This provides placement of all RC components in relatively small place. A2212 motor can rotate around 11100 RPMs at max throttle, then it is gear down 20:28 (differential gear). The differential distributes the power between the front and rear axles, which in my opinion creates less axle load than with just regular 28-tooth double-bevel gears. After joining above components into one setup I received the first prototype: I bought third-party wheels just out of curiosity and I have found that they weight slightly less than Lego ones, with pretty much same radius - 103mm. The body is just something I come up with in one day, I do not worry about that part for now as it is just prototype. At first I wanted to use 23801 steering hubs, but after few test runs with above model they simply couldn't stand the pressure. Other than that, the small steering joints were popping out from wheel hubs during steering on bumpy road. So that left me with only two solutions. Either I will use old portal hubs or new planetary ones. The first ones are more suited for big trucks, at least for me. So the choice was to go with the second option. (We need to wait for the Lego Audi set 42160, hope it will have good steering hubs, that support CV ball joints and are without planetary reduction) With that setup I was afraid that main shaft will have too much speed (around 7900 rpm at max throttle) and axles will start to melt. I was surprised when I took apart the model after hard run, because parts were in perfect shape! Those positive results are I believe because of light weight and short driveshaft. I am far from over with this model, that is why I submitted this topic. There is still room for improvement in those areas (at least :D): - Steering radius is simply poor. I thought that If I will put servo on the front and steering rack as close to the center of front axle it will solve the problem, but appareantly no. If you guys have ideas how to solve that or know any good front axle solutions I will be more than happy. - I need to cover bottom of the car. Shouldn't be problematic, but needs to be pointed out. - Body will be totally new. With 42157 set going soon into my arms and 42136, 42149 already in my hands I will be going with one main color and I believe you know which one I am aiming at. :) - Two-speed gearbox, but It will probably change overhaul look of middle section - Extending rear section. This is tricky one, current solution do not put much stress on axles, but with longer rear driveshaft it would give more "Trophy truck" vibes into it (and I love that :D). Other than stress on axles, this modification will actually shorten steering radius even more, so I am really thinking about implementing it. That's it. If you survived this wall of text I am more than happy. Here is GALLERY for you. Do not hesitate to write under this topic as I am open to suggestions and questions about this MOC.
  7. For those not afraid to mix LEGO with RC components, you might like this one: iWD4. A 100% LEGO chassis and body, driven by 4 brushless drone motors placed inside the wheel hub. In-wheel drive or independent wheel drive. The result is spectacular. Great speed, great control, and hardly any wear-out, since there aren't many moving parts. The rims are LEGO compatible and 3D printed, the electronics are drone based, steering is done by a LEGO compatible Geek servo. Rest is all LEGO, including suspension and removable body. Please have a look at this short intro video. Happy to share more details.
  8. Hello everyone! I am glad to introduce you my Mercedes Unimog U4000. I made it last autumn for trial competitions and it became my first successful RC Lego model with Brushless RC motor. Technical aspects: - Brushless RC motor 1000kv with a custom 3D-printed planetary gear. - Custom 3D-prined planetary 2-speed gearbox with remote control (by Geek Servo) gear ratio 1:1 or 1:5 - RC remote control - 3S Li-Po for power - Geek Servo for steering - Transmission with metal bearings - Planetary wheel hubs - 4-link live axe suspension at the front - 3-link live axe suspension at the rear with free articulation - 85 mm RC tires - Light-weight bodywork, total mass is about 1.2 kg I tested this car on various terrain both indoor and outdoor. It reaches about 8 km/h on normal speed and about 1,6 km on low gear. Since the transmission has several reduction gears (made with planetary gears) Brushless motor feels good in this trial car. It gives the truck more power than it will ever need, so the truck can take a significant weight on board (if one change shocks to the hard one). Oscillating real live-axe and grippy tires provide a constant contact with road, so the truck climbs rocks easily both with closed and open differentials. Due to the reference, the gravity center of the truck is moved to the front, so it struggles a bit with going down the hill, but appears to be a great climber. It can beat Lego Zetros both on low and high gear!
  9. Greetings, Eurobricks! I am proud to introduce you my longest and most complicated project! It took me over 2 months to fix all the technical problems revealed in driving tests. Pathfinder is the universal off-roader built for regular outdoor driving. Features: all wheel drive with remote-control 2-speed gearbox Triangulated 4-link live-axle suspension both at the rear and front Brushless motor 1000 kv, 3S Li-Po, GeekServo, RC LEDs Strong transmission: carbon-fiber axes, metal bearing all around, metal U-joints. Realistic 98 mm RC wheels Underbody protection and custom mudguards Every Boy Dream I guess every Lego boy dreams about technic RC car to play with, at least I did. Since 2014 with a release of a legendary set 9398 Rock Crawler, I wanted to build myself a working and "playable" RC Lego off-roader. I was only fourteen at those days, so it took me a while to save money for a 9398 set. The day of joy turned for me to be the first regret in Lego... I was not satisfied with 9398 performance. I spent a lot of time trying to improve the set, but nether succeeded. Every time I felt the lack of power in my car. At the same time the Lego technic community has been growing in numbers, and many RC Lego off-roaders were shown by technic pioneers. I was inspired the most by Sheepo`s Land rover Defender and RM8`s Toyota Hilux. I decided to build Sheepo`s Defender chassis due to the strict limitation of parts available. Well, that car never moved even with wheels attached. Every time i pushed the gas U-joints in the driveshafts got broken. I guess it was caused by some mistakes I made in the chassis. Anyway, the second regret in RC Lego technic caused me to abandon Lego for 3 years. Time passed and Buwizz brick was presented to the community. It provided more power than the PF battery unit. This bring back my hopes of building and RC car with Lego bricks. My first successful project with a BW2 brick was an RC mod of Chevrolet Corvette. Through the couple of years I upgraded my technic parts collection, which allowed me to try bigger and more ambitious projects. With my RC version Jeep Wrangler the dream come true... A true RC off-roader driven by 4x PF L-motors and powered by BW3 unit provided a good speed and torque. Well, if my goals were achieved with jeep Wrangler, than I should stop my story here... The increased power and speed, revealed another problem: the transmission was struggling from plastic dust and hard outdoor conditions... With my next three project I ensured that there is no pure-Lego solution for this problem. Before going further let me explain the goals I wanted to achieve: Performance over details Efficient and durable transmission protected from dust and axle-wearing Max speed over 8 km/h Rigid chassis, capable to survive big bumps Precise handling (caster angle, proportional steering, physical control) Ground clearance over 3.5 studs, off-road geometric passibility 2-speed remote-control gearbox RC setup adapted to Lego and custom parts It was clear to me that plastic Lego parts would not allow to achieve my goals. The key components that required an upgrade were the wheel hubs and the 5x7 frames which hold differentials. Luckily to me I was not the only person on Earth who had this problems. Few AFOLS in Russia developed their custom wheel hubs and 5x7 frames with metal bearings! I ordered them without asking a price! These parts reinforced the weakest components of Lego cars, which allowed me to build several RC projects, such as: Blue Mamba V2, Wilde Beast and Falcon. This project used not only an improved transmission but also a new RC power and control system, which was able to feed PF motors with a constant stream of power. In fact, the system was so powerful, that PF motors started struggling from over-heating. Since I was in a mood of using custom parts, I get myself a Brushless motor setup adapted to Lego. It was designed by another Russian AFOL: a brushless motor A2212 1000-1200 kv placed in a custom Lego-compatible planetary housing. With a new purely RC electronics I started a new phase of advanced Lego technic engineering. Before challenging myself with a big project I decided to test Brushless motor to see its capabilities. I built a Dragonfly buggy V2 with brushless motor and a Unimog trial truck. Both projects proved the power of a Brushless motor. General layout By gaining experience with a Brushless motor in the Unimog project I decided to build a proper off-roader, which I was dreaming off for many years. Since the brushless motor has the dimensions similar to PF XL motor, I decided to use a classical chassis layout with a steering motor attached to the front axle, Brushless motor placed right behind the dashboard and a battery box in the trunk compartment. My Unimog had a similar layout, so I used it as a reference, though some changes were required. The first and most important change I had in mind was the scale. Since I wanted to drive my SUV outdoors, It should be capable to deal with natural terrain, so It should have a decent ground clearance. This can be achieved with bigger wheels and as a result a bigger scale. The choice of wheels As all of you know, the development of a new car starts with a choice of the wheels, which I have a plenty of. You will joke on me, but a plenty does not mean I have the one I need! Let me explain why. Lego has two most common rim diameters: 1.7 and 2.2 inches in diameter. Unimog used 85 mm RC tires placed onto 1.7 inches rims. Such wheels has a great proportions but they was not big enough for my new project. All bigger wheels were based on 1.7 inch rims. As a result they were disproportionally wide. The two sets of 95 mm RC wheels did not fit the future project as well. I surfed trough the net and found a great set of RC wheels, which you can see now on my Pathfinder. It was another win for me! Transmission Since I wanted to use an RC wheels I had to swap the planetary hubs to to the custom hubs with metal bearings. This swap changed the driving characteristics of a car dramatically as well as caused several crucial problems in transmission. Indeed, planetary hubs took a lot of stress from the transmission away, so I had to reinforce the whole transmission in all possible ways. Firstly, I used the reinforced differentials with 12:28 gear reduction. Further I used carbon fiber axles and metal U-joints. Finally, I used custom parts with metal bearings to divide the transmission from the other car components. This prevent any gear skipping and axle melting. Since I wanted to build a fast SUV but not another crawler, I decided to use open differentials both at the front and rear axles. However, I added an auto-lock system to the rear axle at the beginning of the project, which were removed later for practical purposes. Two drive shafts meet together in the middle transfer box. On the upper end transfer box is connected to the motor through the custom planetary gearbox. Gearbox is remotely controlled and has 1:1 and 1:4 ratios. Transfer box had 24:24 gear combination at first, but after driving tests I decided to slower the car down by putting 20:28 gear reduction instead. It turns out that both planetary gears in the motor and in the gear box require lubrications, otherwise the fast spinning satellites get melted. I learned this lesson in a hard way by having two serious breaks during driving tests. I had to order new parts, that costed me both money and time... Front axle The overall geometry of a front axle was taken from Unimog. I kept the upper suspension 6L links, but changed the lower suspension arms to the brick built one. I still do not understand why, but such combination of links provide a great geometry allowing decent flex angles and a slight positive caster angle (then the suspension get loaded by the weight of a car). At the same time the front axle is well protected from side-to-side wobbling. Reinforced lower suspension links provide a great protection for the front driveshaft. In an unfortunate scenario when springs can not absorb all bump energy, lower links prevent the front axle from being pushed backwards, which saves the driveshaft. The wheel hubs were made specifically for live-axle suspension. In combination with inverted 6L suspension arms they allowed me to build a sturdy and compact front axle. Luckily for me, they fit into the rims of my new wheels perfectly: the pivot point of the wheel sits inside the wheel contact patch. Rear axle Unlike the front axle, the final version of the rear axle differs a lot from the one used in the Unimog. Unimog has a 3-link free-swing rear live-axle, which would not fit a faster SUV with the gravity center moved closer to the rear axle. This was easy to fix by attaching springs to the live-axle itself. The real challenge for me caused the geometry of a rear live-axle. Similar to front axle I wanted to use brick built lower suspension links. I made them few studs longer but the 3-link set up did not work at all! Even without the springs rear axle refused to flex normally. I changed the lower links to the 9L Lego links, which gave me a normal flex angles, but this only revealed another problem. I found that with a 3-link setup the driveshaft moves significantly from side to side as well as changes it`s lengh. This might work for crawlers, but it was totally unacceptible for a fast car, so I had to redesign the rear suspension from scrach. In order to keep the driveshaft from unwanted movements, I made it parallel to the lower suspension links. From one side links have a ball joint and from the other just a regular pin connection. Such construction resists the side-to-side wobbling quite nicely, but uses an admissible plastic deformations to flex (since one end of lower links has a pin connection). The single upper arm was changed to a pair of triangulated links. As a result I achieved a decent geometry of the rear axle. Probably one may ask me why I did not use classical solution for the rear axle, given in Toyota Hilux by RM8? Well, because of scale and my main goals of rigidity. That solution worked greatly for 1:14 scale cars built for indoor trial. As long I was building a bigger car which supposed to achieve higher speeds, I had dial with much higher kinetic energy and thus potential load on suspension and transmission. Thus I had to reinforce the suspension as much as possible as well as reduce any unwanted wobbling. The resulting rear live-axle securely hold the drive shaft and does not cause any load on it. Speed VS off-road capabilities After I finished front and rear axles, I had to choose the spring setup. Lego has a very limited springs variation both in length and hardness. The common solution of this problem is to play with the mounting points. One principle I understood very clearly: the closer springs are attached to the wheels, the better responsibility is achieved. Further, the responsibility of suspension fall down significantly if the springs get attached incorrectly, so they bend with the suspension flex. Further I had to decide how soft I want the spring setup to be. The softer it is the better off-road capabilities, but it does negatively affect overall control and stability on high speed. Since the real SUVs are oriented on the speed and control, I decided to do the same choice. My favourite hard 9.5 L springs come very handy for that. Do not get me wrong, with a proper geometry of the suspension, Pathfinder has a great suspension flex (comparing to the real cars), but it clearly can not compare with mad Rock crawlers. To be honest, I would prefer the springs to be a bit softer (0.8 x current hardness) but Lego does not bother about making good suspension kits. Bodywork My favourite real-live off-roaders are Toyota Land Cruiser Prado and Mitsubishi Pajero sport, but I did not build their replicas due to the low skills in modelling. The shapes of the car appeared naturally for me. Firstly I found that 15L wheel arches perfectly fit to 98 mm wheels. The only 15L wheel arches I had came from Lego set 42069 Extreme adventurer. One of my old projects came in my mind shortly. Once I tried to build a Purple Pickup with parts from 42069 set. Well, I was not happy enough with the overlook of Purple Pickup, but I modified the front part of it to use if the next project, namely Wilde Beast. Now I wanted to modify the front part once more to fit my current project. I wanted to build the car in purple colour once again, but Lego does not produce many parts in purple. I found a great 3-d party set containing a plenty of purple! Namely this was a Sembo Technique 701028 set. Summary Before saying my verdict I want to mention the driving tests I made for Pathfinder. All the following tests are presented in the video. Max speed test: max speed is about 10.5 km/h Turning radius test: 0.86 m Stability and handling test: I tried to dive between cones in Zig-Zag trajectory on max possible speed. After 10 minutes training I was able to drive it with average speed over 5 km/h. Low speed suspension test: The car did not performed good here, to pass it a softer springs required. High speed suspension test: Suspension absorb high speed bumps greatly. High stair test: Due to off-road geometric passibility and high torque Pathfinder passed the test even with open differentials. Almighty hill test: I tested the maximal backward roll-over angle, and car was capable to climb into 60 degree hill. You might say that crawlers can do better, but come on guys, this not a crawler, but a short wheel base SUV! Multiple driving tests showed that such placement of a motor protects it from dirt and dust. However I made an underbody protection and custom mudguards to protect the transmission and the cockpit of the car. Now I can give you the conclusion: This project costed me a lot of money and time to finish, but at the end I get myself a robust RC Lego car, which is very fun to drive around. With this project I showed to the community what is not possible to achieve with pure Lego bricks.
  10. Bit reluctant to post this, since this boat is made of a 3D printed hull, the RIBs are made of insulation tubes, the electronics are all RC parts and the motor is a brushless drone motor. NEVERTHELESS ..... It looks like a LEGO boat, don't you think?! And it works great! Happy to share more details if there is interest, happy to remove it, if it's too little LEGO for the forum.
  11. Hello everyone! I want to share with you my Monster truck that I build for an outdoor winter driving. It has a lot things to improve, but even this imperfect build gives a lot of fun! Yes, this post is mostly not about technical aspects, but about the whole concept and the driving experience it gives! Some highlights: All wheel drive and steering Solid axle suspension with permanently locked differentials Planetary wheel hubs Strong transmission with metal U-joints and metal bearings Brushless motor 1000 kv 3S Li-Po for power 2 GeekServo for steering 120 mm RC wheels with great grip Removable body Together big wheels and powerful motor makes this Monster Truck a real beast. It has both torque and a decent speed. Planetary wheel hubs give enough reduction to obtain the precise control of torque (that is rather unusual for Brushless motors). All wheel steering with deferent steering modes (made as an option of my RC transmitter) bring more fun to the driving. It also increases the climbing abilities of the Truck (as it is shown in the video).
  12. Here is my first attempt of building a rc trophy truck: Thanks to @brickosouch for the Inspiration and sharing the stl files for ball bearing lift arms!
  13. This buggy contains a 3600KV brushless motor (2838). It has a pinion made from a LEGO axle and it runs a seriously good working drive-train. Together with the new 42109 differential and a (new?) 2D suspension method it turns out to be a fun car to drive. Please watch a video here. Especially the suspensions are worth having a look. More and more I'm using custom springs to create all sort of applications. Useful and useless. Almost useless is the spring-lock to open the hood. Very useful are the long front springs and the two-dimensional rear springs. Please let me know your comments. No building instructions available yet. If there is a need, let me know.
  14. Finally finished a first version of a LEGO RC Car with 2 in-wheel, brushless motors. While I know some of you hate the combination of RC electronics and LEGO, others enjoy these hybrid models (hence this post). If you are more the purist type and in favour of LEGO only, please skip this. If you like stretching the envelope using (RC) electronics please have look and let me hear your thoughts. While searching for brushless in-wheel motors I ran into the ideal product: Turnigy Multistar 4225-610Kv. It mounts easily onto LEGO (same measurements) and fits almost any 56-rim. The result is spectacular. Great speed, no wear-out, all traction goes to the wheels, no gears necessary. Sadly, it turns out this motor is no longer available (working on an alternative). Car also includes an (adjustable) software differential running on an Arduino Nano, works surprisingly well. When fully applied the car has serious oversteer, when turned to 0 the car has understeer. The body of the car is a 54100 modified boat hull . It took some cutting but ended up nicely. Please have a look at the video here:
  15. Chanced upon this video while browsing youtube just now... I'm not in any way promoting the use of 3rd party parts () here (it's individuals' tastes after all), but I thought this video pretty much gives a rough gauge to all of us what pure Lego, when combined with brushless motor (i.e. no lubrication, no bearings, no other metallic 3rd party hobby-grade RC structural/mechanical components), can do... how Lego parts (especially differentials and universal joints) survived at such speed, for a roughly 1 kg model (my own model weighs 3 kg and if I accelerate it hard, the rear-front-middle differential and universal joints will complain)... and the control range to be expected using rc-grade transmitter/receiver. and if the speed claimed is accurate, the 68.8 mm wheels would have to be spinning at close to 6k rpm - depending on weather conditions this is probably the top limit before Lego axles melts (this limit will go down the heavier the model is).
  16. Hi folks, This is not for purists. Contains modified and non-LEGO parts. My urge to build a super fast LEGO RC Car often stopped at the stage where the body needed to be build. Seeing all the great designs on forums like this, it somewhat discouraged me building my own. Besides the fact that these bodies come with some weight and will not hold a crash a higher speeds, I had to come up with something else. As a result of an earlier project (building a fast LEGO boat) a had some damaged LEGO Hulls (54779). Since a car body works basically the same as boat hull (but 180 degrees rotated), I thought I'd give it a try. Have a look at the result in the YT video. It works fine. Gives strength to the car, the aerodynamics work well for good driving stability and it is not that ugly :) Called it The LBOW (Lego Boat On Wheels). Included standard RC components: ESC, brushless motor, 3s Lipo battery, digital steering servo and .... a Gyro. Resulted in a very fast RC Car. Theoretically this should be able to reach 100 km/h. Speed test will follow (need to find a good track first). For those trying to do similar things, I'd strongly recommend to add the Gyroscope to your car. It prevents the car from breaking out at higher speeds. Very useful.
  17. Inspired by Lego's Ferrari 599 and Enzo models, I've created something 'beefier' . Main characteristics: Measurements - 50 cm (L), 25 cm (W) and 15 cm (H). Weighs 2.5 kg. All wheel drive (AWD) with 3 open differentials. Full independent suspension. Steering - KPI, Caster, Progressive Camber, sharp steering up to 40 degrees. Towerpro MG995 Servo. Powered by a brushless 4370KV motor at 9 volts . For fun and laughter .
  18. Hey Guys, In this thread I'll introduce my race/trophy truck It features caster, kpi, long-travel suspension (front independent, rear fixed-axle) with damping, RWD, manually functional LED lights, hood, doors, extendable door steps, and moon-roof. Rather sizeable, at 4kg, and 65 (L) x 31 (W) x 30 (H) studs in dimension. Weight distribution is 50:50. And here's how it looks underneath... There was no modification to LEGO pieces, and no 3D printed parts were used. However, I've opted to use 3rd party components (mainly the electronics) because where I live, TLG does not deliver. There is a local shop selling LEGO stuff, but is often poorly stocked when it comes to Technic/PF components. While I do realise that these won't integrate readily with LEGO Technic pieces, and wiring will be messy, I was willing to give it a shot because they offer better performance and configurability. I started off wanting to include a gearbox (at least semi-auto if possible), camber and ackermann, full independent suspension, 4WD, etc. But as you'll see in due course, I encountered challenges either directly or indirectly due to my use of 3rd party components . I will provide more details about these later on. For now, suffice to say that there is some sort of a dilemma here - With LEGO PF, I can probably incorporate all these features, but I'll end up with something that drives like a tortoise (which defeats the purpose of having these features in the first place). However, with 3rd party electronics, I'm able to drive much faster, but that also resulted in the need to build a stronger model to withstand occasional crashes, and stronger drive-train to handle greater torque, and all these bits and pieces add to the resulting weight and size (don't forget that I need additional pieces to act as 'bracing' for the 3rd party electronics too). More details later on... For now, I've prepared a short video: In subsequent posts (assuming that there is sufficient interests), I will describe the challenges that I've encountered, and how they contributed to my current design decisions. Roughly, I'm thinking of elaborating on these areas: - Steering Axle/Hub Design (including how I incorporated a 3rd party servo) - Drive-train Design (why and how I gear down the brushless motor way before the wheel portals) - Suspension Design (why do i use this part, among other things) - Any other areas that you guys want to know more about...