[TC27] City bus

[Erik Leppen]

I think I have found a vehicle type I haven't built before and that is perfect for this competition. My goal is not to win, but to build a nice Technic bus with basic functionality and a nice color scheme. Interestinga bout a bus is the doors on one side which makes the build asymmetric.

Brickshelf folder once public: Brickshelf Gallery - Bus for Eurobricks Technic competition TC27

Progress so far:

Width is 13 studs, height will probably also be 13 studs. As you can maybe see, I'm going for the "low floor city bus" type, not the "long-distance travel coach" type. I think this is a more interesting type because it has less room for stuff so things need to be more compact. Of course, because this is Lego, some compromises will be needed for the low floor.

 

Shot of the bottom, where the door linkage can be seen. Also notice how I used the new 19x3 frames to create a bit of rigidity; in this case using 7x11s etc doesn't really do it, so I'm really happy with these new long frames.

I have the following functions planned and already started:

Steering: I'm using virtual pivot as the default option for this scale nowadays. I'm planning to have a HOG somewhere on the roof (don't know where yet). Goal is to not have axles run through the middle of the walkway, so it's a question where the HOG will be.

Drive: a basic differential between the wheels (no double tyres at the rear), driving a fake engine at the side. I have actually seen city buses that have the engine at the left side, and I like this asymmetric layout because it makes for less "mirroring" in the model. By not making the engine too large, I have room for a very basic 2-speed gearbox. I have room at the bottom and between the steering arms to run an axle all the way to the front so I can have a simple gearstick at the driver's seat.

Doors: At first I thought of having gearing at the top, in the roof, but I'm happy I managed to find a linkage system that can run along the bottom. As always with my models I use red/yellow axles for functions, so I used red for the door linkage.

I have begun a bit of bodywork at the front. I selected green as a color for now, but I don't have that many parts in green so we'll see how it goes. Roof will probably be white (one of the few colors I have enough large panels). Windows might be yellow to match the doors.

 

The side without the doors is a bit less exciting, but I might have different window heights left and right due to the engine/gearbox stuff at the left.

Edited July 15 by Erik Leppen

[Fluwoeb]

Is-is that the One Ring?!?  Looking good! I especially appreciate the virtual pivot steering. Does your door opening mechanism function well? It looks like it might get stuck in the open position at times... but that is probably not an issue, it looks very well designed. 

[efgen86]

A very interesting project. The start looks promising.

[JLiu15]

Having built many bus models with 49.5x20 tires, I'm very excited to see how this build turns out! I like the low-floor design - it's definitely a challenge keeping it low yet reinforced, especially at the front axle due to the steering mechanism, but installing the bodywork helps.

[Paul B Technic]

This is an interesting build, I will be keen to see how it all works out.

[Frequenzberater]

I always appreciate your detailed builds and that one looks promising too. 

One thing, I wonder about:

As I understand, the marked lever turns to the left when opening the door. But there will be a downside movement of the cross axle too. 

How will it be compensated? 

Edited July 16 by Frequenzberater

[Erik Leppen]

I have progress!

I added the wheel arches, and the driver's seat (blue of course). And I added two HOGs: yellow for steering, and red for gearshift (only 2 gears).

 

Also there's some stuff going on in the front:

I connected the steering wheel at the driver's seat to the steering system, and I added a gearstick (orange).

I have found no place for the HOG for the doors yet.

Here's another view of the front section. There's a lot of stuff going on in a small space, it was really fiddly to put together and everything just fits. Also, the whole model isn't really the epitome of structural rigidity. It's all very bendy. I hope the roof wil compensate for that a little, but it probably won't be up to the standard you're used to from sets :)

 

On 7/16/2024 at 7:50 AM, Frequenzberater said:

One thing, I wonder about:

As I understand, the marked lever turns to the left when opening the door. But there will be a downside movement of the cross axle too. 

How will it be compensated? 

It won't be compensated, becaus ethe vertical motion is very limited, so the play in the frictionless pins allows this movement without any problems.

Technically it's not correct, but it works. And yeah, this whole model wouldn't work as a set, it's all too wobbly anyways :D

Here you can see the linkage for the doors from below. The red bits stick out a bit at the bottom, but it's only about 0.3 studs below floor level, so it works without problems.

Edited July 22 by Erik Leppen

[SaperPL]

Shameless plug for reference on the doors:

You can do fairly compact door mechanism fitting within 3 studs and then incorporate the motor into the roof where a lot of modern busses have some HVAC units. You will most likely not make photos showing the ceiling of the bus from the inside, but most of the photos will show the messy floor, that's why it'd make more sense to make clean floor with mechanisms moved under the roof.

I remember Sariel has also figured out some clever door system for his tram recently, so you could look that up as well.

I like the trick with one-rings on the steering rack. I was wondering if the size is actually useful for things like that.

[Erik Leppen]

I have added one of the most important things for buses: seats :D

It's a bit of improvisation putting enough seats in, so I have put a few sideways and a few don't really have any leg room, but the idea is there :)

Also I have noticed that there is a LOT of places where things are only attached with a single pin or axle. It's one of the most flexible builds I have made and I really hope the roof will solidify things a bit.

I have noticed that the driver's seat kinda blends away into all the blue, so I might change the color of that to stand out more.

I've also changed the rear end slightly to fit the seats.

These are probably all the seats I can fit in, also because I ran out of blue 3x5s. (Yes, I know some of the headrests ave blue and dark-gray swapped, but that's because I don't have enough of the same parts in the same color.)

[Seasider]

You get seats, often bench seats sideways in U.K. buses so easily allowable

[Paul B Technic]

This is coming along nicely.

[Erik Leppen]

Quick update, to let you know the project isn't stranded and will hopefully become a finished entry. Will hopefully finish later this weekend.

I have one last surprise feature, which I had in mind and I'm happy that it works:

I don't know what to call it, but it's a set of destination tiles on a band that can roll to show the different destinations. I used the new blue 12t gears which are the smallest gears to work with chains. This plus the 1x8 plates just fits within 3 studs, which is neat. What's nice is that it works with the standard Architecture 1x8 tiles, so it doesn't require custom prints/stickers to work.

I do think the roof is one stud too high so I hope I can make it lower. But the sidways seats above the front wheel are in the way so I will have to change those to make it fit.

Left to do: lowering the roof by 1 stud, adding all the windows (in yellow), closing the roof, and some last details such as side mirrors, lights etc.

Edited August 31 by Erik Leppen

[2GodBDGlory]

Wow, the rotating destination signs are really cool!

It might be an awfully long bus ride between some of those destinations, though! 

[CK28]

This build has a lot of interesting functions, seems to be quite the challenge to fit it all in! I would have never come up with the idea to make a bus for this competition, always funny to see the creativity flourish, hope you make the deadline! 

[Erik Leppen]

I posted the final entry 

I lowered the roof by 1 stud. TO do that I had to make some of the seats above the wheels a bit shorter, but no one will notice :)

Gear changing and steering can be controlled by the driver:

Here's a view into the spacey interior. Also, the driver can even change destinations by rolling the chain by hand, but that's more of a "Lego artifact" and not actually intended of course 

The windows on both sides are quite different:

I also added two rooftop panels that can be opened via the HOG at the rear. The color may be a bit odd but I don't have the pieces in many other fitting colors.

Finally, the shot you'll see if you missed it and have to wait for another 59 minutes...

Seeing the quality of the other entries I'll probably not win, but I had fun building this and I wish all the other entrants the best of luck!

[Good old Lego builder]

I think it is a really fun entrance. I like buses amd this one has a lot of functions in it. Well done!