Trains in 4-Wide

[witchy]

Regarding the drivetrains, here is my standard solution from Planet, a variant of which is also used by John Bull and the Lafayette-ish Norris. The brown goo is tungsten putty from a fishing supplies store, which appears to be by far the best material for ballasting (Planet has about 35 grams of plastic and motor, and I've ballasted it up to 70 grams total weight so far, and it still needs more to be motor-limited rather than adhesion-limited). It sticks to itself more than it sticks to ABS, so you can fill all reasonably accessible cavities in a reversible way as any residue can be swabbed off with a small ball of putty held by fine tweezers. The axle also doesn't need to be metal, I just tried it as another source of ballast (the small bevel gear is also metal, adding another 0.4ish grams to the loco).

The mine cart wheels seem like a significant bottleneck due to their apparently extremely high resistance, so I'm waiting for an order of custom #2 wheels to see if it can be fixed by using Technic axles instead. If even technic axles fail to yield a significant improvement, custom ball bearing wheelsets using 18677 to hold the bearings could be the ultimate solution.

Edited September 4, 2023 by witchy

[witchy]

L&MR trains obviously need some proper L&MR track to run on. Using jumpers for sleepers loosely inspired by Hod Carrier's brickbuilt narrow gauge track, but with a completely different general structure.

The track on the left is easy to make and trains can run on any adjacent pair of tracks (legend says the L&MR track was designed to allow that for oversized loads at off-peak hours, but not all sources agree on what exactly the gauge of the central pair was). The track on the right lines up correctly with stud spacing and is compatible with standard narrow gauge tracks, but the central pair is too narrow for train wheels to fit properly.

Edit:



This version lines up with studs even on the outer plates, but the ballast bed ends up wider.

Edited September 4, 2023 by witchy

[Trekkie99]

On 9/3/2023 at 12:19 PM, witchy said:

1:64 (or, to be precise, I usually scale to 1:62.5 where 1 plate is 20cm/8" and 1 stud is 50cm/20") is a very convenient scale for making people because you have 2 bricks' height for the legs and body, and 2 plates (or more with tall headgear) for the head. The width of such people is roughly 0.5m which is reasonably close to a train seat, so depending on how thick you make the walls of a 6wide coach you can easily get a realistic number of passengers side by side (on the other hand, trying to get 4 minifigs side by side would require the train to be at least 13 studs wide).

'snip'

This isn't a train, but it's another example of what you can do with the scale; a 1830ish Royal Mail stagecoach, with the guard having a bugle and a shotgun. I haven't figured out how exactly to do the horse harness yet (I need to study how actual coach harnesses worked in the period, and the build would probably end up relying on flex hose a lot).

The Houses of the World sets are, incidentally, at a scale that matches these trains and people well enough to be compatible on a layout.

Love your trains!!! I've heard this called midi scale with the five plate tall figurines.

[witchy]

15 hours ago, Trekkie99 said:

Love your trains!!! I've heard this called midi scale with the five plate tall figurines.

Oh, interesting. Midi scale is not a term I've heard before; it appears to be generally somewhat ill-defined with "midi scale" spaceships ranging wildly in their actual scale, with the only uniform factor being that they're a "convenient size" smaller than minifig scale but larger than microscale. I guess in that sense my relatively precisely defined 1:64/1:62.5 counts as a "midi scale", being a convenient size smaller than minifig scale L-gauge but larger than the HOish 4wide, or 2wide micro trains.

Your well-defined 3wide (which seems to translate to a scale around 1:100-120) midi scale work is neat; I especially like the "studs towards end" solution to the SNOT details on the Chicago Metra passenger coaches.

[Trekkie99]

7 hours ago, witchy said:

Oh, interesting. Midi scale is not a term I've heard before; it appears to be generally somewhat ill-defined with "midi scale" spaceships ranging wildly in their actual scale, with the only uniform factor being that they're a "convenient size" smaller than minifig scale but larger than microscale.

Yeah, lots of Star Wars mocs when searching for midi scale.

7 hours ago, witchy said:

Your well-defined 3wide (which seems to translate to a scale around 1:100-120) midi scale work is neat; I especially like the "studs towards end" solution to the SNOT details on the Chicago Metra passenger coaches.

Thank you! I've learned soooooo much from building those, only to have solutions that I'd spent hours on made obsolete by new parts.  Oh well, it just means there's now room for more detail! They're a ton of fun to design.

7 hours ago, witchy said:

I guess in that sense my relatively precisely defined 1:64/1:62.5 counts as a "midi scale", being a convenient size smaller than minifig scale L-gauge but larger than the HOish 4wide, or 2wide micro trains.

This book that may be the original application of the term midi-scale to the five plate tall figs.

https://www.amazon.com/Big-Unofficial-Lego-Builders-Book/dp/3868526587

I'd seen mocs scaled to the five plate figs before such as a Empire State Building, but that book was the first time I'd seen it called midi-scale. 

[witchy]

On 9/9/2023 at 10:50 PM, Trekkie99 said:

This book that may be the original application of the term midi-scale to the five plate tall figs.

https://www.amazon.com/Big-Unofficial-Lego-Builders-Book/dp/3868526587

I'd seen mocs scaled to the five plate figs before such as a Empire State Building, but that book was the first time I'd seen it called midi-scale. 

Alright, so the most established definition of midi scale as a well-defined thing would be 5 plate tall figs, meaning it would be better to have yet another name for the 1:64 scale with 8 plate tall figs.

It's getting hard with all these scale names , what even would be between minifigs and "midi"?

[Trekkie99]

8 hours ago, witchy said:

It's getting hard with all these scale names , what even would be between minifigs and "midi"?

Possibly "mini" which I've never liked cause it sounds like short for "minifig". I have seen people call midi mini lol.

[witchy]

I've upgraded Stephenson's Rocket with a number of improvements, including chimney stays (a regular Lego string) and improvements around the cylinders, especially the feedwater pump on the right cylinder which is now using a golden crowbar. Also, a brickbuilt stretch of accurate L&MR track as a display stand.

More photos at: https://www.flickr.com/photos/198768132@N07/albums/72177720311012954

Studio file and instruction PDF at: https://drive.proton.me/urls/JA2SWZJ9YR#cDelYZR44v0W

Edited September 14, 2023 by witchy

[Feuer Zug]

19 hours ago, witchy said:

I've upgraded Stephenson's Rocket with a number of improvements, including chimney stays (a regular Lego string) and improvements around the cylinders, especially the feedwater pump on the right cylinder which is now using a golden crowbar. Also, a brickbuilt stretch of accurate L&MR track as a display stand.

More photos at: https://www.flickr.com/photos/198768132@N07/albums/72177720311012954

Studio file and instruction PDF at: https://drive.proton.me/urls/JA2SWZJ9YR#cDelYZR44v0W

This is a great micro scale representation of the Rocket. The work on the figures is impressive too. Love their headwear.

[MadDadBricks]

I really love your version of the Rocket @witchy!

Edited September 30, 2023 by MadDadBricks

[JopieK]

I found this nice video / solution:

Thanks you for the great idea Larry's LEGO!

[idlemarvel]

I'm trying to build a 4 wide motorised chassis using only Lego parts, suitable for Powered Up. I wanted to try and build it so that the chassis was inside the wheels and robust. Most of my previous attempts have used Technic lift arms outside the wheels to hold the wheels in place, allowing room for gears, but these always looked a bit ugly and flimsy. Here is my latest effort using a Medium Angular Motor. Excuse poor quality picture.

The construction is all upside down to fasten to the bottom of the motor.

The whole thing is only 3 studs wide apart from the 4L axles so you should be able to easily hide the motor with plates and tiles.

It works but the traction is very very poor as a) no weight and b) only one drive axle. 

There's still the small matter of the battery box to hide. That may have to be in a towed wagon of some kind, but at the moment it might be a challenge to pull it!

It could be made even smaller with a Technic Small Angular Motor #45607 which is available as a Lego Education product and therefore quite expensive, but I have one on order to see if it works.

[idlemarvel]

On 3/24/2024 at 7:53 PM, idlemarvel said:

...it could be made even smaller with a Technic Small Angular Motor #45607 which is available as a Lego Education product and therefore quite expensive, but I have one on order to see if it works.

The Technic Small Angular Motor arrived in the post yesterday. Unlike it's bigger brother it only has an axle socket on the top (rotating wheel) not the bottom. So I had to rebuild the chassis completely, right way up this time. Picture of the model and the studio render without train wheels so you can see the details more easily.

As before, it works, and if you use a Powered Up app you have speed control, but like before the traction is very poor without the weight of a body or battery. It is quite compact and you could probably fit two motors of this size in a 4-wide model, but they are very expensive - about 50 GBP is the best price I have found even if you look for the part number 68488c01 rather than the set #45607. 

[UltraViolet]

  I appreciate any ideas you can bring to the discussion.  Undoubtedly there will be a way to make use of this in some form.

[Stereo]

With something that small, maybe you could just have a rubber band drive to the other axle, on the half bush.

I'd be inclined to build something all technic for rigidity.  The motor has a good number of pinholes to attach plates anyway.  I'm using the 4277 3x5 liftarm with alternating holes here.  You could build it in a 7x11 frame though that's sort of large

[XG BC]

another idea:

the design is inspired by the one in my breuer rangiertraktor, where a rubber band drives the small wheels and acts as a traction band at the same time, its not a very efficient design currently, but gives an input out the top.

 

[XG BC]

to prove that it actually works here is a video:

https://flic.kr/p/2qDKdPj

of course you can use any motor with sufficient torque, i used a modded tower pro sg90 here as its cheap and small. rubber band is this one:
https://www.bricklink.com/v2/catalog/catalogitem.page?id=3320#T=C

Edited January 5 by XG BC

[zephyr1934]

On 1/5/2025 at 11:33 AM, XG BC said:

the design is inspired by the one in my breuer rangiertraktor, where a rubber band drives the small wheels and acts as a traction band at the same time, its not a very efficient design currently, but gives an input out the top.

 

Okay, that's brilliant and pretty amazing that it works too