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Hod Carrier

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Everything posted by Hod Carrier

  1. Hod Carrier
    After designing the lit Oslo tram, I thought I'd play around with Stud.io to see what effects could be attained using the various light settings and luminous parts palette, among other finishes. To give it a real test, I thought I'd push it as far as I felt I could by creating a fully enclosed scene, such as you might find in a London Underground deep tube station. I'd already got a virtual design for a deep tube train, so it just seemed like the natural thing to do. And here is the result. This is a semi-fictional view of a Northern Line service entering the platform at a deep tube station. The scene looks a bit murky, but it is set in the 1960s/70s when the deep tube wasn't as brightly lit as it is now, so I didn't want to go overboard with the lighting. I've included an old-style "lightbox" destination indicator and some period-typical advertising. Part of the problem with rendering in standard LEGO colours is that these parts tend to end up very reflective in the renders, which created a lot of unwanted light effects. To counter this I had to make fairly extensive use of the rubber colour palette and keep the standard finish for sections that would have been tiled rather than painted, as well as the sides of the train. I've rendered this at maximum resolution, which you can find on my Flickr page, to allow folk to see as many of the details as possible and compare the different lighting effects. There's also one or two jokes hidden in there for folk to find. Enjoy!!
  2. Hod Carrier
    Another lovely little model that you've turned your shrinking ray on. You hinted in another thread that you're building British models in 8-wide scale...? I think that's a really good call as the scale certainly works better for you with these smaller prototypes.
  3. Hod Carrier
    Sounds like you're getting through all the various challenges of the design. I'm sure that what we're all waiting for now is the appearance of some real bricks.
  4. Hod Carrier
    Flipping heck!! That's a visual feast. I've looked at Wickhams before and wondered about building one, but they've always seemed too tiny to do any justice to them. I think your approach of bending the scale to fit works very well indeed. Kudos to you, sir.
  5. Hod Carrier
    Another option from the left-field would be to put the train motor on it’s side inside the body of the power car driving a conventional Technic power bogie. It might be a bit of a fiddle to get it set up correctly so that everything aligns properly, but it means that you can have the speed and power you want from the train motor without having to compromise on the size of the bogie.
  6. Hod Carrier
    That's kind of why I started the close-coupling round up thread, so that information and discussion could be focused there rather than being scattered around in different threads. It's easier for anyone who stumbles upon the idea and wants to copy it to find all the information in one place rather than having to search for it in different threads where it really is only a side-topic. I am happy to signpost readers to different parts of other threads if that is considered helpful, but really I'd rather it be done from the thread specifically relating to the topic to show examples where it has been applied.
  7. Hod Carrier
    Always happy to help if I can. Try it and test it out and see how it works out with your trains, as I'll be interested to know the results.
  8. Hod Carrier
    @XG BC That's a great idea for an adjustable link, but unfortunately it's a bit too bulky to work in the railcar. I really need the link to end with pin connectors otherwise there won't be enough space for it to articulate.
  9. Hod Carrier
    That’s for real life.
  10. Hod Carrier
    Further to the issue of setting the length of the diagonal link, I have a quick design for a jig that would help to set the length correctly.
  11. Hod Carrier
    You'll have a conventional power car at each end which will guide the first and last axles, so you shouldn't need to do anything else. The single axles between the cars will be steered by the linkages due to the movement of the cars relative to each other. If a pair of cars make a straight line then the axle between them will be straight. If they make an angle due to the train turning left or right then the axle will be steered left or right. Where you may have a problem is where the train makes a shape that the track doesn't follow. For example, when I tested the articulation for my railcar I noticed that the cars made almost a straight line when going across the S-bends formed by the points/switches in the test track. This isn't a problem for the railcar because it has bogies that can pivot underneath the cars to take in the curves in the track, but it might be a problem for a Talgo because the axles do not steer independently of the cars. As a consequence you may find that your model struggles on complex track like this because the wheels are not following the shape of the track correctly, causing friction and potentially a derailment. This is why I suggest that you try to avoid having lots of bends and points/switches close to each other when you build some track. But you will see this when you get your train built and tested. There's no need. The amount of steering that you get from the linkages will proportional to the movement of the cars relative to each other. On a wide radius curve you'll get less relative movement between the cars which means you'll get less steering effect, while on small radius curves you'll have more relative movement and more steering. The only way to limit the amount of steering effect is to limit the movement between the cars, but then you won't have the flexibility to run the train on standard LEGO track.
  12. Hod Carrier
    It's geometry Jim, but not as we know it. It's possible. Perhaps I'm a little less squeamish than some, but I'm happy to glue these parts to prevent that from happening. That's right. I'd happily take a suggestion.
  13. Hod Carrier
    It's looking good. I think the spacing between the cars is fine, as my railcar uses the same gap and runs OK on R40s, even though it has longer cars than your Talgo. Building and testing your design will show if there's any changes that need to be made.
  14. Hod Carrier
    @Darkkostas25 @Toastie @Selander You're most welcome. I'm always happy to share. The pins/axles pointing upwards is the means of coupling cars together, so the weight of each car is transferred down through the mechanism to the bogie. This should hold everything together and prevent slippage running. The awkward length is to do with the length of the axle that forms part of this linkage. It needs to be @ 3.5L in order to centre things correctly, but no such part exists. I opted to use a 3L axle instead and glued the pin holders to it to ensure adequate strength and to hold it at the right length, but I could have chosen instead to trim down a 4L axle to the right length.
  15. Hod Carrier
    I hope the board will forgive me for duplicating a lot of information already posted, but as it's mostly been scattered across the board in various other topics I thought it would be a good idea to gather it all together in one place for ease of reference and discussion. Other threads were this has been discussed are: LMS Articulated Railcar 1938 - Development of the idea and application for an articulated train My LEGO Renfe S-130 - Use for a Talgo design I had been thinking for a while whether it might be possible to come up with a way to close couple LEGO trains in a way that looks more like real life. After spending a while fiddling around with some Technic parts I came up with the following arrangement that offered a possibility. This design gives a floating pivot point that holds vehicles close in to each other on the straights while still permitting enough movement relative to each other to allow for bend and points/switches. The idea initially was to use this design for conventional bogie vehicles that would need this amount of movement and still centre correctly on the straights, although I am still to test this idea to see how it works in practice. The first application of this idea was in an articulated railcar, but this presented the first problem. I wanted to isolate the rotation of the bogie from the movement of the cars, as would be the case for an articulated train in which neighbouring vehicles share a pivot point, but such a design would not centre itself automatically. The initial solution was to use an elastic band to pull the vehicles back into line, but this was not a very successful idea and actually caused a few more problems than it solved. What the idea needed was another adaptation. The solution was to add an additional diagonal linkage across the car mounting points. This prevents the sideways motion of the linkages that is desirable for bogie vehicles but not on an articulated train. It's an awkward length and requires careful set-up and securing as it's important to get the length absolutely right in order that the cars centre correctly. Get the length wrong and you get an offset between the cars. It turns out that this design also works well for Talgo trains as, in addition to providing close coupling between the cars, it also gives the axle steering effect needed to ensure reduced friction and prevent derailments you might otherwise get with a fixed axle.
  16. Hod Carrier
    I should flag one issue with the design, which I suspect will be a problem whichever solution you choose. The test train struggled to take the points/switches on the test track at low speed and I didn't want to try it any faster because of the risk of derailing. The issue is that the axle is being steered by the movement of the cars relative to each other rather than by the geometry of the track as would be the case with a convention bogie. This means that sometimes it's not being steered in the correct direction to follow the bends. Therefore I do not recommend having lots of corners, bends and points/switches close to each other. It may be worse with my railcar because the cars are longer than would be the case with a Talgo, but testing your finished train on different track configurations will prove the case.
  17. Hod Carrier
    I'm ahead of you. I've done a very quick mod to the LMS Railcar to turn temporarily into a Talgo. This is how I (illegally) attached the wheelset to the close-coupling system. There are a couple of 1x2 jumper plates (in red) hiding deep inside the render which are joined to the pin holes on a pair of 3L Technic pins. I'm not suggesting that this is necessarily the best solution or the one you should follow, but I wanted to make the modification easily with the minimum of new parts to fit the existing layout of the Railcar. The top half of the mechanism isn't shown because I've not changed anything there. So does it work? You know when you've been Talgo'd. (Click on the image for the video) Look between the cars and you can see the self-steering effect. It's not perfect but it's working OK. I suspect that there is an issue with the unequal length of the cars or maybe the weight distribution that could be affecting things. Well, for now I shall wish you luck in your plans and wait to hear what happens.
  18. Hod Carrier
    No, it's complete. The only thing that is missing is the railcar bogie which, because it's a two axle bogie and needs to rotate freely around the central member, is attached using a tile with pin as described last night. The design uses non-friction pins where necessary (all shown in light bley) to ensure free movement. Unlike the double hinge design you've used so far, this design does not give a precise turning point. Instead, the geometry of the parts and the way they turn creates a floating pivot point, which is why it can allow for close coupling compared to a conventional fixed pivot (see first proof of concept photo below). For a Talgo you don't want a free pivoting bogie with just a single axle, as you will have no control over steering. The same as @Ferro-Friki's double hinge design, mine gives you the steering you need to make sure that your train goes around corners smoothly and without derailment. All you need to do is to attach the wheels to the central member (white) in a similar way so that it gives the axle the steering inputs that you need. Looks like a few of us here might be getting a cut, then.
  19. Hod Carrier
    You mean the red one? I got those set to 58 degrees, but I had to work it out using trial and error. What is more important when you build the train for real is to get the length of the red bar correct otherwise the cars won't centre correctly. The axle is about 3.5 studs long, but no such part exists so I have used axles 3 studs long and glued them into the pin connectors to fix the linkage to the correct length. If you mean the black arms, these are set at 30 degrees. The mounting to the cars is 5 wide where they attach and 3 wide where they link to the central member (white). The half liftarms are just there to join the various components in the central member together. There's a Technic axle and pin connector (32184) in the middle of it and the bogies for my railcar connect and pivot through that part using a 2x2 tile with pin (2460). For a Talgo you would want to mount your axle to this white section so that it is fixed to it. You can use different parts to make this happen if it's easier, as this specific design is really for articulated trains with bogies like my railcar. Focus on those first and come back to this later. Employers will be more interested in your exam results than in your ability to build Talgos out of LEGO. It's up to you. If you're just testing out the articulation between the cars, you can just push the train by hand.
  20. Hod Carrier
    @bogieman Thanks Dave.
  21. Hod Carrier
    This is part of the reason for building and testing, so that you can see how things work and whether or not they will work in your own build. It's part #60483. The axle hole is threaded onto the tan axle while the diagonal linkage fits into the pin hole. It will articulate very nicely and give you the steering effect that you need for the rodales. It's basically just a double-hinge mechanism with the diagonal linkage ensuring that movement on one side of the hinge is replicated on the other. On the subject of the articulation and coupling between the cars, I know that both you and @Ferro-Friki were looking at ways of trying to reduce the gap between the cars. As mentioned earlier, I have been working on an adaptation of the close-coupling system that I used on my LMS Articulated Railcar that might also work for Talgos and would be an alternative to the design that @Nikonissen came up with. Scroll to the end of that thread to see the design. I haven't tested it with a Talgo wheel arrangement because the length of the cars is much longer than for your train, but if you swapped out the regular bogie for a fixed axle it should work just the same. The only thing I would say is that I would try and avoid any tight S-bends, such as my test track has, as I fear the system would cause a lot of friction and possibly a derailment too. Coupling to the cars is using the upward-pointing pins and axles, with the pins joining the mechanism firmly to one car while the neighbouring car rests on the axles. All you need is some pin connectors securely fastened into the structure of each car to carry the weight of the car and any forces through the coupling.
  22. Hod Carrier
    Sorry for bringing this back up from the depths, but I wanted to post an update. As I mentioned during the building phase of the project, I was not entirely satisfied with the close coupling system I had employed for this build as it wasn't very well optimised for an articulated train. Part of the problem was that the geometry did not automatically centre the cars which meant that found myself having to resort to using strong elastic bands to achieve this, plus it did not fully separate the articulation of the cars from the rotation of the bogies. It was an OK solution but not ideal as it caused a few unwanted side-effects, such as causing the fully-articulated middle car to lean alarmingly outwards on any curves due to the change in the weight distribution as a consequence of the pivot point shifting with the articulation. It also needed a very strong pull to achieve any centreing. After a good long break from the build I decided that I needed to revisit the design and address these problems and try to come up with something a bit better. And here is the fruit of my labours. The innovation is the diagonal linkage (coloured red). This provides the force to centre the cars and also acts to stabilise the middle car to prevent it from leaning. It has necessitated a bit of a redesign inside the railcar to accommodate all the changes, but these alterations now allow for the coupling gap to be shortened if necessary for larger radius curves. I have also altered the design of the central member (coloured white) to make it more compact. The results are just as I had hoped. The cars now articulate independently of the bogies and the middle car is now stabilised. It can still negotiate R40 radius curves and handles points/switches with ease. Here's a couple of very short videos of it in action.
  23. Hod Carrier
    Ah, I get it now. You've got two problems with attaching the skirts to the bogie. The first one is the half stud offset I discussed yesterday, which should be easy enough to fix. The second is that big issue that affects all 7-wide builds, which is that you have a quarter plate left over on each side and there isn't a part with a quarter plate thickness to deal with it. This is a much tougher puzzle. I always like to try and keep things simple if it avoids having to deal with a really tricky problem head-on. The first thing I would explore is whether the side-skirts can be attached to the body of the car and still leave enough space inside for the bogie to move as much as you need it to. If you can make this happen it will completely avoid all the other problems as well as look better when the train is running. Only when I have exhausted all the possibilities over this would I start to consider how I might try to attach the skirts to the bogie.
  24. Hod Carrier
    Dark blue is VERY dark. I have some parts in my bin in that colour, and it's hard to tell them apart from black. Looking at photos of Sir Nigel together with Mallard, I would say that they are both almost the same shade of blue. There isn't a huge difference between BR Blue (which really doesn't look purple in real life) and LNER Garter Blue. They look different because Sir Nigel no longer has the streamlined wheel and motion covers which accentuates the amount of black visible. It also has banding over the casing, whereas Mallard is simply plain blue. Also, bear in mind that looking at photos online can also be misleading where colour is concerned, as there are any number of factors that can affect how it can be presented and reproduced. In some pictures, Mallard can appear almost azure. I vote standard LEGO blue for both. I think you've done a grand job at capturing the shape of an A4. The only nit I would pick over the styling would be that the lower front casing should taper inwards on both sides where the buffer are fitted. I'm also a little confused about the configuration of the drivers. Do you not need more than one set of flanged drivers?
  25. Hod Carrier
    That might not be a massive problem. If the weight is being supported by the bottom link the attachment at the top is there really just for dynamic stability (in other words, so that the cars don't wobble too much), so you may not need to build it as strong. It's possible that I might just have something in the pipeline that could help you gentlemen. I have been working on an adaptation of the close coupling technique I used on the LMS Articulated Railcar, specifically for articulated trains using Jacobs bogies. Depending on how this works out, it might just work for a Talgo also. The problem at the moment is that I don't have a lot of spare time to get the thing built and tested, but when I do I will report back and let folk know how it went together with some ideas about how it might apply to Talgos. I mean, it's a high-speed train so it needs bigger curves so that it can stretch it's legs a bit. It's nice if a train can be made to work even on R40s because then it can run anywhere, but you are right about them being limiting. If you want to get close to anything like scale modelling with LEGO they really are useless for anything other than trams. I'm unsure if I've understood what you're trying to make happen. Are you trying to get the light bley brackets holding the side skirts to connect with the bogie arm? Is there not enough space inside the skirts to have them fixed to the body and still leave enough room inside for the bogie arm to swing? You might have to approach the problem from the opposite end. Sometimes the solution to a design issue is not obvious and there could be more than one solution to the problem. Brackets, as with any part that has an open stud (as opposed to a solid stud), can provide you with the means to create a half stud offset. Any plate that is 1 x N has little studs on the back which will fit inside an open stud and secure parts together, which is a feature that Stud.io supports. So rather than starting off by fitting the brackets to the inside of the skirts and then stressing about how you can attach them to the bogie, maybe fix the brackets to the bogie first and then see what options you have for fitting the skirts to the brackets.
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