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Didumos69

Eurobricks Dukes
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Everything posted by Didumos69

  1. Didumos69
    I cannot really judge whether the looks match the original - I'm actually impressed by those who are able to point out what could be done better - but it already looks absolutely amazing to me. I suppose the black 20t gears under the rear window are HoGs for shifting and steering? And maybe I missed something, but I was wondering whether you have been able to improve the operation of the paddle shifters?
  2. Didumos69
    Yeah, it's hard to get the wheels aligned properly with all these angles and Ackermann steering. On the Steppenwolf I optimized for pushing the car forward and I limited the steering to guarantee a successful return. Max steering angle was still over 40 degree. When pushing the car backwards it suffered from a little toe-in. I also had to build an 8L gear rack. When the steering links don't make enough angle with the wheel hubs, steering gets sloppy. This problem is more likely to occur with Ackermann steering. I've seen people bringing the gear rack closer to the axles to make sure the steering link-wheel hub angle averages around 90 degree. This shows what I mean: Nice to see someone using the tilted wheel hub idea from the Steppenwolf
  3. Didumos69
    I like your search for a properly angled steering geometry. Nice to see some details. Very clever how you secured the CV-joint. Given your geometry, I guess this was needed because the axle inserted into the U-joint will slide in and out of the CV-joint. The 3L thin lever could still slide over the 3L axles with knob, but I guess that won't happen. I would also very much like to see your custom wheel hubs.
  4. Didumos69
    Okay, thanks for pointing this out. If I understand correctly you're saying that 90 degree bevel gear meshes generate friction when steering gets harder due to increasing weight. I'll see what I can do. This HoG steering is giving me more headaches than the entire build sofar.
  5. Didumos69
    Haha, I'm affraid you're right Jeroen! But it turns out I'm a lucky guy too. The odd number of 90 degree meshes easily makes you think the steering wheel will always be 1 tooth out of center - in this case 1 tooth of the last 12t gear. That would be true if it wasn't the angle made by the U-joints to align with the tilted dashboard that compensates for that perfectly. Here's a short - unlisted, bad-quality - video in which I fixed the steering wheel in centered position and try to show what I mean. It also shows how the slack in the steering gears averages around the center position. The fact that the 2 U-joints are not correctly aligned and the 2L axle was not inserted was because I didn't want to put in the effort in LDD. And here's a video showing the HoG in operation. The HoG works the same, but the steering wheel operates with less slack compared to the situation with 3 8t gears. I think this is a more elegant solution:
  6. Didumos69
    I know . It feels like I'm Winston Wolf (Harvey Keitel, Pulp Fiction) and could walk in anywhere with my bag full of pieces and speak the legendary words: "I'm Winston Wolf, I solve problems. LEGO problems." Sorry for off-topic bull...
  7. Didumos69
    Yeah, you're right. I did exactly the the same in my Steppenwolf. I did need to add an extra half bush to secure the end of the CV-joint inserted into the diff though. Otherwise the CV-joints would eventually get pulled out of the diff because the distance between the CV-joint and the U-joint varied in turns.
  8. Didumos69
    Good to have you back in business, both professionally and Technically. Cheers!
  9. Didumos69
    I wasn't really content with the HoG steering. I simply don't like three 8t gears in a row, they come with a lot of slack and make steering with the steering wheel quite unpleasant. Only had time to work in LDD lately, but I think I have found a better way to combine a working steering wheel with HoG steering. Would this be better? I also did some work to reduce lengthwise twisting of the entire structure. Now I have to find some time to build this. The black 7x5 liftarms are intended as the base of the driver's cage.
  10. Didumos69
    Didn't know about kneebine mechanism, but makes a lot of sense. Now all weight is carried by a few teeth of the 8t gears. About the orientation of liftarms. I could not have explained it as well as you did, but I have the same belief. You can partly overcome the falling apart issue by locking up these beams vertically, so they can't go up or down, but in the end the structure will bend more easily when carrying weight. I have another tick that helps me to establish a firm and logical main structure: I tend to work in horizontal layers. The odd layers have lengthwise beams and the even layers have widthwise beam. Everything tied together with orthogonal connectors such as - of course - vertically placed 3x5 frames. This is also convenient for axles running through the length of the car; I usually have them running through the even layers with widthwise beams. 8 hours straight! Wow, interesting way of working. I have a completely different way of working. I spend most time in LDD, where I do most of the pre-work. Every spare 15 minutes that I have you find me building behind my laptop, for instance when traveling from and to my work. I've learned my lessons when it comes to sloppyness and friction so I more or less know the dos and donts when building in LDD, but still real life building always comes with surprises. I think I spend max 4 ours a week on real life building. Mostly during lunch breaks. I have all my LEGO pieces and my build in a big black bag that I carry around all the time .
  11. Didumos69
    You could also collect all your fun facts in a single topic called 'Richard Dowers Breaking News'.
  12. Didumos69
    Just watched the video. The frame appears to be very sturdy and the air ride works solidly. I do have some concerns about the height of the whole setup. It seems that the top of the front suspension module is already at the level where you would expect the hood. My feeling is that it should be possible to make this more compact. Also for aesthetics I think it would look better if the springs where attached to the lower A-arm. Anyway, very interesting alltogether. I'm looking forward to seeing your next steps!
  13. Didumos69
    Great to see you doing a WIP-topic! Very original project and it looks massive! Will watch the video later, I don't have Wi-Fi right now.
  14. Didumos69
    Over the weekend I geared down the steering and had my go at HoG steering. As rightly mentioned by @Lipko this should be included. This also solved the 6.5L axle issue between the two steering U-joints - also addressed by @Ludo Visser a few posts back. The HoG serves as the primary steering device for playing. The steering wheel of course also operates but suffers from a little more slack because of the extra gears. I geared down by 12:20 by replacing 2 of the 4 bevel gears at the front of the front axles module. I could reduce by 12:20 once more, but it seems okay to me like this. Personally, I'm not a big fan of putting gears in a row to translate rotation, but this way I could hold on to the 'elegance' of the u-joints and the HoG works very smoothly. The HoG is also quite compact and solid; maybe it's hard to see, but besides the toggle joint, the HoG axle is also held in place by a pinhole with pin inserted in the red #2 connector nearby. Feel free to comment. It'll only help me make this model better.
  15. Didumos69
    I assume you have applied the errata. There must be something generating friction in your drivetrain, which gets most apparent in 1st gear when all unengaged axles need to rotate faster. My guess is that it is one of the unengaged axles or the engine. There should be so little friction that the drivetrain runs smooth in all gears. It's not easy to make all axles run smooithly. You have to make sure all individual axles run smooth and all red clutch gears have max play. Something I usually do to locate the friction: I take of the wheels or put the RND-lever in neutral. With one hand I push the grey bevel gears in the H-frame manually to set the drivetrain in motion. Then, when the friction is most noticeable, I reduce the hand-power up until the point where the drivetrain halts. I keep pushing the grey bevel gear, but just not enough to put the drivetrain in motion. Now I check all potentially problematic axles and clutch gears with my other hand. Axles or gears that feel as if they are tied somehow or even clamped are likely suffering from friction directly. Axles that feel loose and have some play do not. I hope this helps.
  16. Didumos69
    I guess I should. However, to motorize drive, steering and shifting I'm afraid I would have to redesign the whole thing. But this might very well be my next project. I would like to see a motorized vehicle that can actually use the gearbox as it was meant to be used: to shift gears smoothly while driving and actually take the speed of the vehicle up to the next level, gear by gear. Thanks @brunojj1! The diagonal beams are actually the result of my first exploration into the bodywork. But they turned out to give just the necessary rigidity if you regard the chassis as something self-reliant. Nevertheless I'm more and more moving into the direction of making a minimal body that adds rigidity and prevents the longitudinal twist. Just like what you're suggesting with a stable roof. Or a firmly secured roll-over bar. So I expect the diagonal beams to be something temporary. You're welcome! Here you can see the difference between 'torsion bar attached' (left) and 'torsion bar detached' (right): I don't know yet. 4L u-joints are not an option for me. The ones I have, have become very fragile and I prefer using present-day parts only. But I somehow like to hold on to the u-joints, they add to the overall elegance of the chassis in my opinion. And even though the 2L axle in the middle is only inserted by 3/4 stud into the axle connectors, the whole thing sits very secure between the two u-joints. I didn't look over that area for days and nothing happened with it, not even after some monkey tests. And when it comes to 'strictly legal techniques', my torsion bars are not strictly legal either. I do agree I should gear down the steering though, but I can also very easily do that with the gears at the front side of the front suspension. I can even reduce by 12:20 twice. Then again, I'm currently working on the HoG steering and like @Lipko indicated, this might affect the whole steering setup. Who knows where that will go.
  17. Didumos69
    I think it's temporary anyway. It came along with the rest of the 'Christmas' look.
  18. Didumos69
    Very nice moc! The proportions look perfect and this one shows that stacking beams - when done neatly - can turn out very well. Thanks for sharing!
  19. Didumos69
    Both motorized functions and design are very original and very well done. Thanks for sharing!
  20. Didumos69
    Thanks! Don't worry, I will add HoG steering. There enough space in the area just behind the dashboard. Yeah, Paul's model rocks and it was in fact one of the triggers to start my own awd chassis. Apart from the engine - with the 16t gear inside - I followed my own path and could come up with something quite different. After replacing the hard shocks with normal ones both the anti-roll bars and the torsion bars really make a difference. When I decouple the torsion bars, the shocks are to weak to carry the car by themselves. The nice thing about torsion bars is that their resistance starts subtle and increases fast when they get twisted. This makes dropping the car possible without having the bottom of the car touch the ground. And the shocks actually work as absorbers this way. They absorb the jumping spring effect of the torsion bars. The effect of the anti-roll bars is harder to observe. However compressing only one side of for instance the front suspension is significantly harder with the anti-roll bar than without. You can feel the difference. Your suggestion to leave it like this - as demonstration stuff - is tempting. Bodywork is not really my cup of tea, but I do have some aspirations there. It might also be a starting point or study material for others as you can easily leave things out. You can skip the torsion bars and/or the anti-roll bars. You can also quite easily skip the entire front drive and replace the central diff with a 24t gear and a 16t gear. I think I will first make a minimal - beam only - body, also to draw the attention away from the bulky anti-roll bars a little. And then I will take the take time for a more advanced body. I know that's what you would like to see. I'm still awaiting my son to enter motorized Technic sets .
  21. Didumos69
    That makes sense. When you use the tightly sitting pinhole-pin part as in my example you can partly overcome the connection not being in-line with its endpoints. With the drawbacks you describe, like not being able to attach anything to it, I agree that this is not something that one would use as part of the core structure of something. I guess it's more of a means to make auxiliary/secondary connections, just like in my example. The fact that it turns out to reduce twist in my chassis - even with the double hinges at the endpoints - is probably because it is used quite far away from the twist axis and works as a kind of stabilizing lever. I have to admit that I was also excited about how it looked . The discussion about the practical value of this is very useful, but I also remain to be interested in whether anyone knows a practical example .
  22. Didumos69
    You indeed need more complex hinges, and indeed the pinhole-pin part sits so tight that it partly overcomes that drawback. I tested the chassis stiffness before and after and it made quite a difference, it especially reduced twist. The chassis was already quite stiff when it comes to normal bending, but the narrow console between the seats did allow for some twist. It feels much more rigid now.
  23. Didumos69
    Does anyone - consciously or unconsciously - make use of Pythagorean quadruples in his/her Technic builds? Or does anybody know examples that make use of these kind of quadruples? As we all know triangular connections help making stiff constructions. And as Technic is particularly well suited for building right angle connections on a one stud grid, it is most convenient to find right triangles that only have whole-integer side lengths. Such triangles in fact make Pythagorean triples. Triples that we often use: (3, 4, 5) and (5, 12, 13). You could say that with Pythagorean triples we can make connections that span two dimensions: The (3, 4, 5)-triangle spans 3 studs in one dimension, 4 studs in the other dimension and together that makes a 5 stud span. The (3, 4, 5)-triple is even supported by Technic's angled liftarms. However, with LEGO we build in 3 dimensions, right? So we may also want to make triangular connections that span all three dimensions. And if we want to do so on a one stud grid we can make use of Pythagorean quadruples. For instance the well-known triples (3, 4, 5) and (5, 12, 13) can be combined in a quadruple (3, 4, 12, 13) where the 5 in the second triple is obtained using the first triple. This would look like this: Other useful quadruples are: (1, 2, 2, 3), (2, 3, 6, 7), (1, 4, 8, 9), (4, 4, 7, 9), (2, 6, 9, 11), (6, 6, 7, 11) and (3, 4, 12, 13). There are more, but they exceed the max liftarm length. Now what I would like to know is whether you know about LEGO Technic examples that make use of these kind of quadruples. Do you?
  24. Didumos69
    Thanks! The same things bothered me and a few more: Ground clearance, suspension travel, gearbox routed through the entire chassis, etc. Btw, the gearbox can be simplified even further when there would not be an engine on top. In that case the 4 axles to the side of the central diff can be replaced by two above the diff, between the driving rings and clutch gears. More functions? I want to have HoG steering, openable doors, openable hood etc as part of the bodywork. But the chassis is done as far as I'm concerned. I finally received my 8 red normal springs and replaced the yellow hard ones with them. Makes a lot more fun! The idea is to tweak the suspension by adjusting the way the torsion bar running through each upper wishbone is secured. With the softer springs this works out very well too! I will have to wait and see how they behave with the extra weight of the body later on, but for now the red normal spring seem to be the right choice. When the body weight requires more resistance, I can always revert to the yellow hard springs. This is how I secured the torsion bars at this stage:
  25. Didumos69
    I appreciate your pledge for authenticity and there will for sure be others that feel the same way, but in my opinion authenticity need not always be the single most important objective. There was so much 'wrong' with the Porsche and there were a few very playable functions missing, such as HoG steering and HoG shifting. That's how I got to my 'playability' objective. As for the McPherson suspension. I would like to see someone come up with a McPherson setup that is solid - as in not sloppy - and fits the stock body, or at least doesn't change the outer look of it. One problem I foresee is that you will have to move the steering axis away from the center of the wheel, which will cause the wheel to take more space when steering. The wheel will probably collide with the body.
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