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Didumos69

Eurobricks Dukes
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Everything posted by Didumos69

  1. Didumos69
    So cool! My son wants instructions! He has this model and added fake front and rear lights himself, but this would really finish it off!
  2. Didumos69
    Very nice! You made yourrself a factory that makes boxes out of boxes, haha. A so-called identity-factory .
  3. Didumos69
    This is so cool! You must be having a thorough understanding of pneumatics and even better, you have the skill to implement your ideas perfectly. A big compliment and good luck in the competition!
  4. Didumos69
    I made some adjustments to make it possible to have two independent axles running right through the middle of the unit. I needed that myself to route drive and steering from the rear side to the front side. LXF-file here (the silicon bands need to be routed over the yellow bushes and yellow half bushes inside the unit, I will post a video soon).
  5. Didumos69
    Nice to see how this is progressing. I'm amazed how small the movement is that is needed to make shifts. It seems you do need quite some power to shift though, but still okay I think. The paddle unit reminds me of this one (he uses a lot more silicon than you do of course ): But you're video makes me even more curious about how this magic shifting box behind the driver seat works. You seem to have hidden its contents carefully. Could you tell or show us a little more about what's inside that box? And about the limiter at the back: I suppose the #2 connector will be braced better, because this way it will eventually slide off the shift axle. Btw, I just read this complete thread and I really like the goals you have set and the fact that it will be a pure manual model. I will be following this more closely.
  6. Didumos69
    Thanks guys! I don't have a problem with it either. I've been using axles as torsion bars in suspension setups for whole my Technic life. Like in the 8845 mod below, haha (note also the Ackermann steering ). Nevertheless, the version of this stepper that does use silicon bands operates more smooth than this one. The nice thing about silicon bands is that they give a fairly constant stress, almost independent of how far you stretch them. As opposed to that, the resistance of axles used as torsion bars does increase significantly when you twist the axle further.
  7. Didumos69
    The boat is a great novelty! And I like the looks of the concept car even more, especially how the red and white parts seem to be separate components in a perfect marriage. Well done!
  8. Didumos69
    Thanks! I tend to make use of axles as torsion bars more often. But also for me there is a fine line between do's and dont's. I would for instance never - or at least not deliberately - make use of slack in parts to make something work.
  9. Didumos69
    Yes, that would for sure be a workaround. Btw, here is the LXF-file of this MOD, but I see you already sorted it out yourself.
  10. Didumos69
    Thanks! Something purely mechanical, that would indeed be cool. I had something like the above setup without anything elastic. It relied on friction in the shift axle and the shift lever had to be pulled far enough to make a complete shift and had to be returned manually. But it could result in non-90-degree positions if the shift lever wasn't pulled far enough. I might look into that once more...
  11. Didumos69
    If you don't like things that use axles as torsion bars, then please skip this topic. In the march of steppers, shifters and limiters, here's my throw at a 90 degree stepper without silicon or rubber. I started off with my compact 90 degree stepper which uses silicon bands for returning the shift lever as well as for limiting the shift axle to 90 degree orientations. Because the rotation movements that had to be limited are quite small (max 10 degrees), using axles as torsion bars seemed to be a valid option that wouldn't put too much stress on the axles involved. After some trial and error I found a setup that actually works. It uses 3L axles with knob and half pins (also with knob) with a flat round 1x1 tile attached to them as stoppers and pole reverser handles as torsion levers. In idle state, there's practically no torsion stress on any of the involved axles. Only when you pull the shift lever, the axles get twisted, but not more than about 10 degrees for the shift lever and even less for the 90 degree limiter. The casing had to be made quite strong to prevent any other bending then the intended axle torsion. LXF-file here.
  12. Didumos69
    I get it. I visited Lego World last weekend and there was a Lego fan demonstrating the Porsche. He used a motor to show the shifting mechanism and after a few shifts the entire setup stalled because of double engaged gears. I hope you'll do better . Good luck and have fun building!
  13. Didumos69
    I'm not really into dual differential steering, but this seems like a nice compact design. Is it common to use a worm gear for the steering input? I know LEGO worm gears induce a lot of friction when used in high torque applications. They push themselves hard against the pieces holding them. Maybe that is part of the grinding problem at low speed.
  14. Didumos69
    Cool! It appears that the a full shift is only completed when you return the shift lever. Does it return by itself or do you actually need to mobe the lever back manually?
  15. Didumos69
    Thanks for this extensive report. It's always good when people make their own analysis and try to understand what the exact problem is with the Porsche. Still, if you want to get the shifting mechanism working properly, I strongly advice you to add the simple 90 degree limiter and remove the 8t gears that are supposed to reduce backlash in the shifting mechanism. That will make the biggest difference when it comes to reducing the chances of double engagement. And when you have that working, you can extend the change-over catches with half a stud again. That will reduce friction in the gearbox. Btw, I suppose you already know about the complete set of must-have improvements on Rebrickable. P.S. I also wonder why they used change-over catches in the paddle shifter unit in the first place. They could have done with a more subtle stop-and-return setup which would have allowed for a shorter paddle movement at the same time:
  16. Didumos69
    Although these wheel hubs look strong and we see similar ones around a lot, I doubt whether they are really that strong. The weak part is that the triangular levers bracing the gears are only attached to two horizontally aligned axles. Bumps and weight of the vehicle will induce vertical powers and introduce slack in these parts regardless of the axles being with end-stop or not. The only reason that we see vehicles with this type of wheel hubs standing on zero camber wheels is because of the flat tyres. With the big rims that you're using it should be possible to make something more sturdy.
  17. Didumos69
    Very nice! I also like this kind of rugged down-to-earth builds. It shows what Technic is all about in my opininion.
  18. Didumos69
    Cool! But you're not telling us that we're gonna have to wait until after Christmas . It will be hard to do without changing the bodywork...
  19. Didumos69
    I also think the new hubs are more versatile, but when it comes to slack in the hub itself, I did not experience any difference between the two versions. The slack in the LEGO wheel hubs has been reported by many already. You could always consider replacing them with nicjasno's modified turn table wheel hubs, which have considerably less slack. http://www.lpepower.com/products/small-turntable-wheel-hub
  20. Didumos69
    I think that should be posible and it might actually turn out better. I needed the yellow ones in my ultimately playable build but in that case the strength of the stock shocks was reduced because I also used the full length of the suspension arms.
  21. Didumos69
    In my perception the most straight forward way to improve the front ground clearance was posted here, see first image below. To maintain a correct rake angle you may want to combine this with a very easy way to improve the rear ground clearance as well: see this post and second image below (btw, the latter post also shows the front axles that I use in my ultimately playable build, it also includes Ackermann steering and a gear rack slider). If that would lift the rear too much you could try combining it with mounting the rear shocks to the lower suspension arms one stud closer to the wheels.
  22. Didumos69
    I thought I should at least make a short note on how I got to this. I got inspired by @Attika's compact sequential stepper. His stepper triggered me to try and see whether I could apply the same concept to the paddle shifter unit of the Porsche. Although I got that working quite nicely, the issue with it was that the paddles needed to travel extensively to make a single shift: And when I integrated it into my Porsche it was still not enough to actually shift gears. This also had to do with the fact that in my case it had to set quite a few things in motion, not only the driving rings in the gearbox, but also the HoG shifter and the dashboard gear indicator. So I reverted to the original Porsche paddle shifting mechanism and re-established the side knob gears. But this time with a renewed casing and more importantly, a more simple and reliable way to catch and return the side knob gears, without using any moving change-over catches or rubber connectors: This simplified catch-and-return setup allowed the side knob gears to be aligned perfectly to the left and right sides of the center knob gear when the paddles are in idle position. This did not only result in a significantly shorter travel of the paddles to shift gears, but it also made this catch-return concept suitable for operating in two directions. And that's exactly what this stepper does, albeit with slightly different catch-return stoppers.
  23. Didumos69
    Here's a cutaway showing the essentials of the mechanism:
  24. Didumos69
    Indeed a very compact 2-speed switch. Can the center-part of the slip gear be removed easily? I don't have that part at hand.
  25. Didumos69
    @Attika, @aeh5040, @Paul Boratko, thank you guys! Indeed the shift lever is not fixed to an axle. I don't think this mechanism is particularly useful in a motorized gear changing setup.
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