DaFokka

Eurobricks Vassals
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Everything posted by DaFokka

  1. Promobricks has images of the H2 sets. https://www.promobricks.de/lego-technic-sommer-2020-bilder/102934/ I'm not sure of the Volvo Articulated Hauler. €250 for a just three functions seems a little steep. EDIT: Took out the images themselves because they were too large.
  2. The Ballkirk Wheel is a GBC based on the Falkirk Wheel ship lift near Falkirk, Scotland. If you want to see it in action, go straight to the video: Conception I love the concept of GBC and I wanted to build an original GBC module. Ten years ago I got the idea of using the Falkirk wheel. Its continuous mechanism should be just as good at lifting balls as it is at is at lifting ships. Unfortunately back then the inner hole of a large turntable was not large enough to accommodate a 14mm ball plus lane. The only alternative was to use Hailfire Droid wheels but since I was not quite ready to sell a kidney to support my hobby, I dropped the idea. Fast forward ten years and I revisited the idea. @jojoguy10 built a LEGO version of the Falkirk wheel, but noone had made a GBC module out of it yet. The new large studless turntables have no gears in the centre hole, which means that it's (just) large enough to fit through a lane with balls. So I ordered six of them from Bricklink and started building. Building Process When prototyping I tend to use a mix of colors. This limits search time and makes it easier to discern individual bricks. Once a module is finalised, I recreate it in Stud.io so I know how to rebuild it when my BrickLink orders arrive. This is the first time I used a CAD program during the building process. I had no experience with MLCad or LDD and I started out with the newest kid on the block, Stud.io. There are still a few kinks to iron out but I think Stud.io has a great balance of simplicity and power. Gondola orientation The orienting mechanism makes sure that both gondolas stay upright during the entire rotation. This prevents balls and boats from being spilled. The principle is demonstrated by this video: LEGO was actually used by the designers to demonstrate the mechanism for the Fallkirk Wheel. My implementation is very straightforward. The center turntable gear stays stationary. As the wheel revolves, the smaller gears between the center turntable and the outer turntables cancel out the rotation of the gondola, thus keeping it upright: Retarding Mechanism The most challenging part of the build was the intermittent rotation mechanism. The wheel needs to pause shortly to load and unload the balls. Initially, I wanted to use a mechanical solution for this. I have experimented with many different solutions, none of them satisfactory. I started out using a rotating cam that would temporarily block the rotation of the wheel. This did work but it was very imprecise and jerky: In movie projectors and watches something called a Geneva Drive is used, but I did not succeed in creating a version with sufficient angular precision to reliable loading of the balls. Another possibility involves a sliding mechanism on a piston driver, thus first converting rotating motion into intermittent linear motion and then back to intermittent rotating motion. Although motion was smoother than with the cam mechanism or the Geneva drive, it was even less precise and more bulky. Eventually I caved and just used a Mindstorms NXT to drive the wheel. The program is exceedingly simple: Rotate 900 degrees at 80% power Wait for 1500ms Repeat I'd be really interested if someone comes up with a mechanical mechanism, because using software to solve this issue feels like cheating to me. Loading Hopper Since the mechanism completes one cycle every three seconds, on average three balls should be lifted during each cycle to comply with the capacity of 1 ball per second which is required by the standard. For this, a pusher is located at the bottom of the hopper like in Akiyuki's Ball Cleaner. For the mechanism, I took my inspiration from @Lasse D's ball pump. A counterweight on the back of the hopper smooths pusher movement. I currently feel the pusher is the weak point in the contraption. Because it is driven by the same motor as the wheel, it spends half the time not loading any balls, thus limiting capacity. Since 5 balls fit on the piston simultaneously, theoretical maximum capacity is 1.66 balls per second. But when multiple balls are stacked in the hopper, the pusher loads less balls per cycle, limiting capacity. One solution would be to use a second motor to continuously drive the pusher but I prefer the contraption to be driven by a single motor. Controlling Ball Flow The balls move through the wheel because the entire assembly is tilted. The incline is 1 brick per 15 studs, or 1 plate per 5 studs. This corresponds to an angle of 8% or about 5°. The balls should only move when the wheel runs are oriented with the input and output runs. For this both the input run and the gondola runs are equipped with gates that are closed when the wheel is in transit: As usual, the simplest solution turned out to be the most reliable. A sliding gate is held town by gravity. The input gate is opened by two 42610c02 wheels [LINK] mounted at the end of the arms, which sadly are not available in Stud.IO. The output gates are opened by the gears of the orienting mechanism, as illustrated in the following image: Reliability The biggest challenge of a GBC is making it reliable. Those little balls have a mind of their own and tend to find every nook and cranny of your contraption to escape it, jam it or even break it altogether. I tested the contraption with beads with large holes which get stuck easier than the standard balls. The Ballkirk Wheel has gone through several revisions to improve reliability: Incread the incline to prevent balls from stopping in the middle of a run Like 7 versions of the input and output gates Enlarged the hopper and the pusher for greater capacity Several modifications to the pusher to reduce friction and increase reliability Addition of a counterweight to the pusher for smoother operation Added a shield to prevent ball spillage at the exit lane Added a bumper at the foot of the back support to push back balls that have missed the exit Together, these improvements have resulted in a fairly reliable GBC. I have tested the Ballkirk Wheel for an hour of continuous operation with no blockages and only one ball spilled. Maximum throughput is about 1.4 balls per second. Summary Thanks for reading this far, I hope you enjoyed it! Please let me know what you think! I haven't gotten around to creating instructions and I'm not sure I ever will. However, if you'd like to recreate this contraption, you can download the stud.io file: Ballkirk Wheel.io - Stud.io file.
  3. My girlfriend gave me the 4260 Road Work Crew for the holidays (you can see her present in the back of the pictures). I thought it'd be fun to have a go at building a C-Model. I grew up in a rural community and combine harvesters were a common sight in my youth. Without further ado, this is the result: The model has the following functionality: The mower drives the conveyor The conveyor almost reaches the hopper The hopper can be disconnected Rear-wheel steering The model is more fragile than I would have liked but this is the best I could manage with the limited part selection. The colours, stickers and the anniversary brick work out quite nicely. Some more pictures can be found in the Instagram post.
  4. DaFokka

    10261 LEGO Creator Expert Roller Coaster

    I have finished building this behemoth and here are some thoughts: The build can get a bit repetitive. This is the first time I have ever wished for a non-seniorized (the forum replaces the term I wanted to use with '<insert that tiresome argument>' ) piece. I am sure your fingers will do the same after sliding 300+ white round bricks on technic axles. The pacing of the build is great though. The coaster is divided in two sections which take roughly the same time to build. Each section starts out by laying out the floor plan. Then the supporting frame is built. Fitting the roller coaster pieces is very satisfying. Inbetween there are some awesome mini-builds to break up the monotony. The stalls and the cotton candy car (in the Netherlands they are called suikerspinnen or sugar spiders) are nice but my favourite is the COASTER logo, which just is a work of art in itself. The finished model is just huge. Make sure you actually have room to display it. It genuinely is a marvelous display piece and people of all ages will love to play with it (at least all my employees did). The main attraction () of the model is its functionality. The roller coaster performs splendidly. The chain lift, the pusher wheels at the top, the siding, the station brake and the pusher wheel at the station all work together very well. The station pusher wheel has a limiting mechanism so you can't turn it the wrong way. My only criticism is that the main drive should have a similar system. if you add a PF M motor, you can put the roller coaster in a continuous loop, which works equally well. In what must have been over 200 rounds, the train has not gotten stuck once. Of course, you have to be vary careful to make sure everything is connected properly but once it is, it tends to stay put. The coaster comes with two three-car trains. It is also possible to join them together to form a six car train, but some minor modifications are needed. The wheels on the top tend to conflict which each other. This is easily solved by removing the first and the third pusher wheel. The six car train is a bit slower and more stable, but it won't fit in the station. I guess it all comes down to preference. Unless you want to build bigger coasters (and why wouldn't you), this is a poor parts pack. There are 200+ chain links, 300+ white round bricks and 150+ green 2x2 jumper plates but there must be cheaper ways to get them than a €350 set.
  5. DaFokka

    2018 Friends Sets - Rumours and Discussion

    I don't know why they added the arrows, but they are oriented the wrong way. If the prop would rotate clockwise, the plane would move backward.
  6. DaFokka

    2018 Lego Trains

    It looks like 8 red train windows are included, as well as 6 big train wheels in black EDIT: Looks like I'm wrong on both counts. The windows are not of the classic train type. And there are 4 big train wheels with a flange and 2 big ones without a flange. Still, it looks like a great loc!
  7. DaFokka

    2018 Lego Trains

    It looks trans black to me on the images released on brickset (you can find them earlier in this thread).
  8. DaFokka

    2018 Lego Trains

    Pics of both sets are available at Brickset. This is the freight train:
  9. DaFokka

    10261 LEGO Creator Expert Roller Coaster

    I just managed to place an order (I am in the Netherlands). It is not showing up in my order list though and I haven't received a confirmation e-mail. Fingers crossed!
  10. DaFokka

    [GBC] Upslide

    That's a nice GBC. Kudo's on the video! I think it's great you didn't put in your own music - the balls have a rhythm of their own.
  11. Did you consider moving the driving wheels to the sides of the track? That way you could lower the center of gravity considerably, which should lessen the wobbling by quite a bit. It might also help with the steering.
  12. DaFokka

    2018 Lego Trains

    What if the bright colours are for the young child and the Bluetooth is for us? A man can dream, no?
  13. DaFokka

    2018 Lego Trains

    Actually, I think the Duplo train is the most exciting innovation. I suppose those 'smart bricks' contain some kind of RFID chip. If that is the case, it would be possible to build stuff like block signals or switches based on the train content.
  14. I ordered one from A-Tembo in the Netherlands yesterday, got delivered today. At €143 (plus €5 shipping) it was a pretty good deal too.
  15. DaFokka

    [MOC] Dual-voltage (9V-12V) GySEV Vectron locomotive

    When I read the title I did not expect this to be an actual dual voltage loc ;). Great work!
  16. Awesome, I've been obsessively refreshing your channel for the last couple of days!
  17. DaFokka

    [REVIEW] 75192 - Millennium Falcon

    Your reviews are always a joy to read. A bit of humour, some obscure details and great photography: 5/5, would read again.
  18. DaFokka

    Can you ever have too much Lego?

    One way to limit the amount of space needed is to build in two passes. In the first pass, you ignore colors altogether. This simplifies searching since the search space is smaller. Once you are fully content with structure and functionality, you will know exactly how many bricks you need in which color. Now you can gather all the parts from your collection, which is much more efficient than searching during the build. Of course, if you are really lazy, you can also order the parts from BrickLink and outsource the searching ;).
  19. Nice mechanism, smooth operation and great photography. Really a nice GBC!
  20. DaFokka

    21309 NASA Apollo Saturn V (LEGO Ideas)

    Mine arrived a week ago but I only built it yesterday since it was a birthday present to myself. That wait definitely took some self-control :D. I agree with almost everyone here: This is a great set, possibly my favourite ever. Of course the subject matter is epic. But the build itself is lovely from the first to the 1969th brick (actually, brick #1969 is the brick separator but let's not split hairs ;)). Building this set is an excellent way to appreciate the sheer scale of the Saturn V. The build is subdivided in 12 sealed bags. The last one contains command module, the escape rocket, the lander, the service module, the splashed down command module, the stands, the lunar diorama and the payload fairing. The remaining 11 bags are dedicated to building the three stages that propel the relatively tiny service module+lander to a lunar intercept trajectory. Sometimes I change round the order of the bags to make for a more interesting build, but in this case building bottom-up is a great way to appreciate the dimensions and structure of the rocket. The build is a masterclass in SNOT techniques. Almost every technique in the book is used to create an attractive shape, an impressive level of detail and a surprisingly sturdy model. Last but not least: If you would want to use this set as a parts pack (which I would consider heresy, by the way), you'll never need to bricklink another SNOT connector ever since the set is absolutely filled with them. This set is a must-have. If you don't get it, you will regret it.
  21. DaFokka

    21309 NASA Apollo Saturn V (LEGO Ideas)

    Amazing. I ordered mine on wednesday night 9PM (the Netherlands) and it was already on backorder. No indication as to the delivery date.
  22. Hi Doug, it's nice to see how inventive you are. You are running into some of the problems I've also run into, although I haven't explored the mechanism as thoroughly as you have. The problem is that the mechanism both needs to provide quite some torque, needs to be very precise and also needs to run smoothly. I'm curious to see if the stronger differential will make a difference
  23. Lower left: This is a turntable. It allows you to rotate one structure in relation to another one like for instance the turret of a tank. Top left: This cam can be used in camshaft mechanisms. Also, it allows for a 1.5 stud offset which can be useful in some mechanisms, especially crankshafts Bottom middle: These gearboxes allows easy fitting of a worm wheel and a 24t gear for a 1:24 reduction in rotational speed and a 24x increase in torque. Center left: This is a differential, allowing the outer driven wheel to turn faster than the inner one in a turn Center Right: This is a clutch, used in gearboxes. You'll need additional parts for it. Right: These rods are used for suspension in cases there there needs to be more than one degree of freedom