keymaker

I know it can sound like pointless and wrong way to go, but what about adding two more motors to your simple model? It won't be 200g/motor for sure, but maybe you will get like closer to 300g/motror instead of 400g/motor?

Hi, I usually do not create WIP topics for my MOCs, especially from the beginning of work on project. But I decided to give it a try in this case. I hope it will be fun and useful at the same time for me and at least some of you I would like to continue the Snowrunner series I started with my Chevrolet CK1500. So the next project will be unnamed (yet) 6x6 off-road truck. As I am going to use 30mm rims, this truck will be quite similar to my first “official” MOC – KrAZ 255. The plan is to include all mandatory features I plan for vehicles in this series and to create truck, which will be an improvement in every aspect when compared to KrAZ 255. The mandatory features for all vehicles in this series are: RC drive and steering All wheel drive Suspension for all wheels RC winch I of course started already and did some work, so let’s move to designing and building section to have something to discuss. As usual, I decided to start with the front axle, which is in my opinion the most complicated element of the MOC. As mentioned earlier, my plan is to improve basically every aspect of KrAZ’s elements and make truck, which at the end I won’t be ashamed to put next to my most advanced and successful MOC – UAZ 3151. Start conditions for front axle comparing to KrAZ's axle are: keeping 11 studs wide for standard 30mm rims keeping using of live axle improving ground clearance from 2 to 3 studs improving pivot point for wheels making the axle comparable with new tractor tires make axle smaller, as compact as possible As I spent some time and developed couple of versions of axles, I would like to share some short story behind designing process. All axles were built in real life and tested quite extensively. Axle 0 – KrAZ 255 I still like this one, even if I know what problems are hidden there. Everyone can build this one, using free instruction on rebrickable for KrAZ mentioned earlier, or from yt video like this or this. Long story short, this is the starting point and reference level which I use to compare the final version of axle. Axle 1 – Chevrolet CK1500 I designed this axle with plan to improve in my opinion the most important thing in off-roading – ground clearance. So I increased it from 2 studs to 3 studs which, I believe, is the maximum with those rims and tires. I also tried approach where there are no shock absorbers and the axle is suspended only on swing arms, which uses 2 studs rubber pieces. It was success and my Chevrolet is very capable off-roader, which you can check here, but at the same time I learnt what are pros and cons of such type of suspensions. Axle 2 After dealing with ground clearance problem, I decided to address second issue – terrible pivot point which was located 3 studs from center of the rim. With such distant pivot point, wheel needs a lot of space to operate and steering is also inefficient. I was able to improve it drastically, switching from cardans to CV jonts, using a lot of half-studs technics and new mustang rims. As the result, I decreased distance of pivot point from 3 studs to only 1 stud from the center of the rim, which is also in my opinion the maximum, if you are considering making steering axle also a driven one. I even added ackerman geometry, but as I was told later, it was reverse ackerman geometry… So it couldn’t be the end of designing. Axle 3 Here the first thing to address was reverse ackerman geometry. I fixed that quite easy by putting steering rack behind the axle and getting proper ackerman geometry. Next things I wanted to improve were reliability of steering rack and steering input angle, which was 90 degrees and it is caused by using CV joints. I almost did that, almost… I needed one tile of height to make this work, but all I got was half of stud. So this version of axle turns out to be a failure because 0.17 stud. But not a completely failure since I learnt that 180 degrees of input movement for steering is possible even when using CV jonts. Axle 4 I believe this version had the biggest number of variations, changes, different concepts, but all in the range of the main construction. I will only describe the final form. As you may noticed, since the version of axle no. 1 I still didn’t back to the shock absorbers used in the KrAZ axle. There was the case in axle 4 also, but after many changes I decided, that I like shocks more than rubber pieces (because of couple of reasons). So the final version again is using shock absorbers. I also fixed the problem of one dimension mounting point visible in KrAZ axle. Now shock are connected to the axle in a way allowing them to move in two dimensions. So no more stresses for shocks. So what was the improvement regarding the Axle 3? This one worked, and it worked beautifully. Axle 5 "the final" So why next version, if axle 4 works so great? Two reasons: I wanted to make it smaller, I believed I’m able to make it one stud shorter. And in this scale of building, one stud is a lot and compactness is the king. Second thing was steering input angle. I couldn’t forget the solution I learnt during working on failure axle 3, which allows increasing input range from 90 to full 180 degrees of movement. It is important because bigger range of movement – more precise steering and secondly, 180 degrees makes this version PF servo friendly. At the end, I was able to do that and this is the final version of front axle, were I thought over every single part in it trying to find the way something can work better, or to work the same but to look more “clean”. And when I was thinking, that I did everything I could, @Fluwoebshowed up with this topic and I couldn't resist myself to give this idea a try. It opened so many possibilities unavailable in such scale. Because if I can have double, independent input, then I can use differential, which cannot be located directly on axle without losing ground clearance. And if I can have differential, then I can have locking differential as well, so I had to try. Especially that differentials with locks aren’t common thing in models in such small scale and I love to have one since this feature is one of the main features for vehicles in Snowrunner. I knew it will be a hard one, so I started slowly... Axle 4 – double input As axle 4 was big enough and the strongest one from all my versions I prepared, after a couple of tries, version of axle 4 which had all the features as original and double independent drive was done. I wasn't easy, but couple small things (like for example 1,5 stud deep hole instead of 1 stud deep in CV joints) made this constructions possible. Axle 5 – double input - The Final version It was inevitable, that as before, I will try to prepare double input version of axle 5. I spent couple of long evenings looking for optimal solutions and dealing with many problems which pop out like crazy, when you want to squeeze so many thing in such a tiny space. But at the end, I believe I delivered. List of most important features of this axle (there is more, but if you were able to reach this place you have probably enough of reading :D): 3 studs of ground clearance great pivot point, located just one stud from the center of the rim 180 degrees of input for steering, which makes it PF servo friendly ackerman geometry included independent drive for each wheel, which allows to use differential I am sorry for such long post. I hope some of you will find it interesting. I'm going to think about next thing on my list, and it will be "power distributor" which is also present in KrAZ and since this truck is going to use such a complicated front axle, then it needs such module too. And I definitely need a break from working on axles :D

But do you realize, that I can tell a lot about the Moon even if I have never been there? Or about dinosaurs without ever meeting a single one. And i do not know why you assumed I have never had other brands in my hands... You sound like you being offended because someone dared to tell something bad about you favorite brand. Most of non Lego brands, especially in technic elements have shitty tolerance and quality. It is the fact, grow up and deal with it. At the same time LEGO sets are often overpriced and TLG is messing with us not letting us to buy new parts on their official website. It it also the fact. That's life.

@aFrInaTi0n, @Toastie I use over 90% of technic elements in my MOCs, so the quality and tolerance are crucial here. And fortunatelly I feel I reached the amount of bricks (>40k, but some of them are locked in "shelf models") that I do not need to force myself any more to expand my technic collection of elements. I feel I can build anything I want, so the price of LEGO is not so concernig for me as I do not need more elements.

I also heard a lot, that those other brands are so great and the quality is at the same level as LEGO, it isn't. I perfectly aware, that LEGO some times is crazy with prizes, especially lately with those all rises. As the result, I am choosing new sets more carefully. And I must say, that in this year there were more interesting sets in Creator Expert line than in Technic line.

I think there is no point to focus on words. It is super easy to find point where gears touch each other but they skip practically with minimal torque. To sum up, as you said, this setting is unusable.

I do not base on photos, I have those parts in my hands. Such connection skips and jams frequently and it is definitely not reliable. I do not need your images or video. I have those parts. Such connection skips and jams frequently and it is definitely not reliable. I would not recommend such solution in any project with any torque involved.

It doesn't. Do not confuse people.

You can use for example https://bricksafe.com/ to host images.

The problem is (at least in my opinion) related to power (current) spikes during start/stop and lack of software protection against it. How to protect your MOC against it? Change gearing in a way, that there will be less torque required from motors (lower torque = lover power/current consumption). In my case it was change from 16T/16T (motor/wheel) to 12T/20T.

I did, with my Armored Trophy Truck. I needed to change gearing a little to reduce power consumption during starts/stops. There is no solution for this problem as far as I know.

Yes, with those rims and tires changing from 2 studs GC to 3 studs GC is a major and very impactful change, which improves off-road capabilities tremendously.

I saw it at premiere and I will write it here also: It is great video and very imformative, I definatelly rewatch it a couple of times when I will be at body designing in my next MOCs. Any news when the final part will be available?

Very interesting idea, especially with those double shaft drive train. Pivot point and rims from mustang are also great pick, I am working on something similar, you can check first attempts here. But my goal is to have 3 studs ground clearance.

I like suspension and drivetrain, what is more, truck looks great and I probably couldn't create better body, but I need to point out, that in this statement: " Clearance: 4-5 studs " you exaggerated, by far.

I added to the description couple of small (mostly technical) facts about this MOC, which can be missed because they are hidden under rather simple body: front and rear axles are connected to the chassis only by 4 ball connections, no suspension elements directly connected to the axles, yet they stay in place and axles have suspension suspension uses rubber pieces which allows to very compact and space efficient construction, thanks to that for example rear bed can be located very low – considering fully working suspended rear axle even if suspension has a lot of travel already, it is equipped with limiters, which have 2 levels of limitation or they can be easily removed to largely increase travel of suspension drive train has four places, where gearing can be adjust, it gives a lot of room for experimentation and choosing your own speed to torque ratio all wheels have disk breaks it works greatly also with standard 30x20mm rims or 30x14mm rims – you only need to removed disk brakes doors have “locks” to keep them in place, they do not rely only on friction between parts all electronics is hidden in the floor and power source on passenger place, thanks to that you get clean look, removable rear part of the body and fully equipped driver seat with steering wheel and central column, all of this with keeping great three studs ground clearance which is achievement in such scale and with used rims & tires I also upgraded list of free additions in the first post.

I did not know, that they send packages directly from Poland... Either way, polish post sucks, I fully agree.

When do you plan to air next episode?

I won't tell no, but it can be tricky. PF servo is 1 stud shorter than PU L motor.

I made some additions to this MOC, small trailer and foldable crane. Both are available on rebrickable for free. They will fit to the most of small scale models. I made a video for short presentation. Trailer features: • live axle with suspension • openable crate for tools • lockable, liftable and foldable support for undisturbed ground clearance Crane features: • compact size when retracted • located on platform with lockable and foldable supports • three separately operated sections • rope on drum with lock • full 360 degree movement with stabilizer Building instructions Crane: https://rebrickable.com/mocs/MOC-114764/keymaker/foldable-crane/#details Building instructions Trailer: https://rebrickable.com/mocs/MOC-114766/keymaker/small-trailer/#details

You broke the system! :D All parts on your list are not available on PaB. But if they sent you them, so there is a chance they will be available to order soon.

PaB pack ordered 30.05.2022, sent not sure when but received today so 14.06.2022. It is pretty fast as for our post office :P No new frames unfortunately but I got some parts I also wanted.

Same date of order like you, but my order was sent couple days ago. So I am waiting.

New system is indeed tedious and frustrating. I deal with it by looking for based on number of part or number of set where the part is and then sorting by price from the highest. Because part I am looking for are usually the most expensive parts from the set.

24 : 10 19: 6 30: 4 26: 3 4: 2 14: 1