OcTRAINber 2019: Cartoon Train - Casey Jr.

[Daedalus304]

Hello everybody! I'm back again with another build, but this one is quite different from my usual style.

This year's OcTRAINber is themed around Technic, or more specifically using Technic to add extra motion to a train (Or train-related) build that isn't critical to its functionality - so something beyond just the usual wheels and rods. I knew immediately what I wanted to do!

My son, currently 5, really loves the cartoon movie Dumbo and especially so Casey Jr., since he just generally loves trains (Lucky me!). I've wanted to build a LEGO Casey Jr. for a while now, but there are quite a lot of Casey Jr models out there already and I've wanted to take a different approach to the build. And so my concept for my entry this year was "Building a Cartoon", where my intention was to do some studying of animation and animation techniques - quickly, mind you, I'd only a month - and try to build a locomotive that moves like a cartoon does. The motions aren't meant to perfectly copy any one cartoon locomotive, rather, to take some of these animation principles and see if I couldn't apply them in a way mechanically that made the model feel like a cartoon.

I'll go ahead and share a couple pictures of the completed model, and then share also my WIP progression - since one of the fun things I did as a part of OcTRAINber this year was to document the process, and what an unusual process it was this time! I also have a video, which I'll have at the end since for some reason when I try to embed Flickr videos it makes a very strange, enormous white space.

My  model of Casey Jr. is very small, but has a lot of functions. This is an entry into the Indirect Drive category - where the extra motions are not driven  directly by a motor, but passively as the train moves. The locomotive has 3 special extra  motions, which I will go over in the WIP summaries, and the passenger car contains the motor and other electronics to push the engine along. 

WIP Step 1 - "Key Frames" and the "Principles of Animation"

So once I'd decided on what I wanted to do, I had an idea or two for what sorts of mechanisms I could try. But I wanted to learn more about animation and see if I could get some help or inspiration from that, and wouldn't you know it, Walt Disney himself had "12 Principles of Animation" that were used for all the cartoons. I'd also learned previously about a concept known as "Key Frames" in animation, when watching videos explaining animations for certain old NES games. From looking into these, I ended up deciding on three primary functions, which would actually mix together and create a more fluid and complex motion.

#1 was a bobbing smoke stack - but I didn't want it to be a smooth motion, rather a sudden "pop" up. I also didn't want it to pop constantly, which led me to plan out the gearing so that it would only pop every 2-ish rotations of the drivers.
#2 was a Back-and-Forth motion to the pistons, to sort of give the impression that the pistons themselves were sort of "rowing" the wheels to turn them. From my research into the Principles of Animation, I felt that this would feel a lot more dynamic if the pistons were on bars to sway, instead of rails to slide. Rotational motion feels more organic and an exaggerated rotational motion was going to be much more "Cartoony" than a straight front-to-back, since it would mean that the pistons would also vary slightly in how wide out away from the locomotive they were as well.
#3 was a rotation sway of the entire upper half of the engine. In addition to having the extra liveliness of the rotational motion, proper timing of the sway could also enhance the "rowing" effect and make it look like the whole engine, not just the pistons, was putting effort into pushing those wheels.

I did a test build of the engine in LDD, and got screenshots of my "Key Frames", including the mechanisms that would actuate them. Those can be seen here:
 

Spoiler

 

With those set, it was time to test bench it.

WIP Step 2: Mechanical Proof of Concept

At this point, I'd already sketched out my functions and the way they should work and ordered my parts. But I needed to get a head start on making sure all these functions  actually worked together in the brick - that's a lot of swaying about Casey Jr is going to be doing, and surely a lot of fine-tuning involved as well. 

The first thing to do was verify the motion of the pistons and swaying would work out. So this quick test rig was put together:

Spoiler

 

This round of testing went really well, and I learned a few things about the proper spacing and timings needed to get the engine to function running both forwards and back. It ended up being pretty specific, actually. And so, the test build grew some more to include the 3rd function:
 

Spoiler

 

It was at this point that I came to realize that I had a problem that I was going to have to figure out. Casey Jr is an incredibly small locomotive  with very little weight (roughly 200 pieces, actually), and worse still - the weight was perfectly balanced over the middle driver. This meant that when pushing the engine, or when breathing too hard across the room, the engine would tip forward, and lose half the traction. Further still, BBB Medium drivers are very flat on the back and can add a lot of extra friction of their own. On a heavier engine or one powered directly by a motor, this isn't a huge issue, but it was taking a huge bite out of the very little tractive effort Casey Jr had. With no room to add any more weight, and also needing to avoid adding more weight above the turntable (to manage how much mass had to be shimmied around, and adding still more friction to the bill), I jumped straight into step 3.

WIP Step 3: The Articulation

Originally, I'd been planning on 4 flanged drivers and having the pilot truck be on a sway-arm. The lack of weight left me with only one option that I could see - and I immediately ordered 2 BBB Medium Drivers with O-Rings. The extra traction provided by the O-ring tires was the only way this was going to work - but how to apply them most efficiently? So again I went into a testing phase. I found that the mechanisms worked the smoothest when the rear axle was the one being directly driven, which makes sense since the rear axle drives both the piston function and the sway directly. But with the locomotive's weight distribution, the rear axle was the one that would lift off the track. Because of this, I tried out a new chassis - with the pilot truck fixed to the body and the front driver "blind". This seemed like it would keep the engine from tipping over the centerpoint. I would have 2 fewer drivers contributing to the power, but I was hopeful that the traction bands would more than make up for it.

Keeping the first chassis style in mind as an option, I swapped the build from the one on the left, to the one on the right:

Spoiler

By this point, BMR had announced an extension to the contest, coincidentally on the same day I found my BBB Drivers to were to arrive on the 31st. I could probably have hit that deadline, I thought, but I was glad to know I had more time if needed.

It turns out, I did need it. One of my Drivers had arrived missing the o-ring, and one single O-ring just wasn't enough. (I did get in contact with Ben about this, and he sent off a new one - very awesome and quick support) So I made a trip down to the hardware store to pick up a replacement O-ring  to use while I waited for the new one from Ben, and while I was there, I was thinking a lot about the other issue: The friction caused by the back of the drivers. It was still eating up a TON of my tractive effort - but what to do? And then I remembered BMR's Bearing Wheelsets, or more specifically, the little washer they have between the wheels and the Technic bricks. Worth a shot! So I picked up 4 washers in addition.

With all of the new parts installed, and decals from OKBrickworks applied, I was finally able to do my final test run. Would this whole thing finally work smoothly? And boy, was I so excited to see that it did. After all that, Casey Jr ran smoothly and capably. I guess I forgot to mention that I had to build a passenger car there during all of that - a much less interesting story, except that it started out as a 6-wide until I saw the Disney Train coaches in person and realized how much better the passenger car would  be in 8-wide. 

Speaking of the passenger car, it wasn't until after I'd ordered the stickers that I realized something interesting: I'd been using the HD re-release of Dumbo for my reference images, because I hoped it would have cleaner still images. What I hadn't realized is that at some point, the texture/design on the side of the passenger car changed - from a planked/ribbed look in the original film to the one you see now on my model in the HD re-release. Why they would change that, I do not know.

I hope that this model does well in the OcTRAINber competition, but no matter the outcome, I'm very pleased with the end result. I really enjoy the way it turned out, and more importantly, my son who inspired me to build this engine absolutely loves it. The last two weeks, he's been singing Casey Jr.'s  theme song, and as soon as I get home from work every day he wants to see, play with, and talk about Casey Jr.; and even more fun, he's gone and built one himself out of his Duplo. This has been such a fun thing to share with him, and to see him inspired to build something of his own makes me very happy. I can't wait to see what else he builds, someday.

Edited November 3, 2019 by Daedalus304

[LEGO Train 12 Volts]

Very nice locomotive ...it would be great see a video of the steam engine in action!

[Daedalus304]

3 hours ago, LEGO Train 12 Volts said:

Very nice locomotive ...it would be great see a video of the steam engine in action!

Flickr's embed for videos is pretty bad, but that last image is the video. I'll upload it to YouTube later and post with that so it's more clear.

Update: The video has been uploaded to my YouTube channel and is now right at the start of the post.

Edited November 4, 2019 by Daedalus304

[zephyr1934]

Wow, that's some crazy workings you had going on, but it came out great!

[SteamSewnEmpire]

I clicked on this expecting nothing, and was really, REALLY surprised and impressed. What an excellent rendition of the engine.

[Daedalus304]

3 hours ago, zephyr1934 said:

Wow, that's some crazy workings you had going on, but it came out great!

Thanks! I'm really glad that it all came together and ended up working. I have to admit I was starting to really worry near the end there. 

43 minutes ago, SteamSewnEmpire said:

I clicked on this expecting nothing, and was really, REALLY surprised and impressed. What an excellent rendition of the engine.

I don't blame you for not expecting much!! Casey Jr. Is probably among the most common of subjects for people to build, and it was kind of a risky choice for a contest because it's been done to death. I've been really blown away to hear all the positive feedback on it. Thank you for taking the time to check it out! I'm really glad to have managed to leave an impression.

[LEGO Train 12 Volts]

Wow, very cool! 

[SteamSewnEmpire]

13 hours ago, Daedalus304 said:

Thanks! I'm really glad that it all came together and ended up working. I have to admit I was starting to really worry near the end there. 

I don't blame you for not expecting much!! Casey Jr. Is probably among the most common of subjects for people to build, and it was kind of a risky choice for a contest because it's been done to death. I've been really blown away to hear all the positive feedback on it. Thank you for taking the time to check it out! I'm really glad to have managed to leave an impression.

Given the widespread popularity of the subject - I know Casey Jr's scenes (especially with the thunderstorm closing in) were some of the chief inspirations for many of us at a young age in our collective love of trains - are you thinking of selling instructions (once the competition is over)? I wouldn't mind having one of these on the shelf. 

Edited November 4, 2019 by SteamSewnEmpire

[Daedalus304]

55 minutes ago, SteamSewnEmpire said:

Given the widespread popularity of the subject - I know Casey Jr's scenes (especially with the thunderstorm closing in) were some of the chief inspirations for many of us at a young age in our collective love of trains - are you thinking of selling instructions (once the competition is over)? I wouldn't mind having one of these on the shelf. 

I have considered it a little bit. The model is very small, but to balance all three functions it actually needs a lot of precision that I worry would be hard to express in an instruction manual. Certain details like the sway crank for the body need to be timed pretty specifically to the motion of the rods, making sure that spacings are just right for the rest of the technic bits, etc. Once it's all together correctly it works very reliably, but it takes a lot of trial and error to get it calibrated just right. I don't think it would be a good building experience, and I wouldn't want people to end up frustrated with it.

If I were to take out the side-to-side sway of the upper body, leaving the piston motion and the popping smokestack, it would greatly simplify things and I could make instructions for that pretty easily. But would it still have the same charm, and would anyone want that version? I'm not sure. 

So, I haven't really planned to do it. But if a lot of people want them, and would be ok with a version with less motion, let me know and I can look into it. I can't/won't make any promises, but I'd at the very least consider it and see what it would take to get something good out.

Edited November 4, 2019 by Daedalus304

[SteamSewnEmpire]

50 minutes ago, Daedalus304 said:

I have considered it a little bit. The model is very small, but to balance all three functions it actually needs a lot of precision that I worry would be hard to express in an instruction manual. Certain details like the sway crank for the body need to be timed pretty specifically to the motion of the rods, making sure that spacings are just right for the rest of the technic bits, etc. Once it's all together correctly it works very reliably, but it takes a lot of trial and error to get it calibrated just right. I don't think it would be a good building experience, and I wouldn't want people to end up frustrated with it.

If I were to take out the side-to-side sway of the upper body, leaving the piston motion and the popping smokestack, it would greatly simplify things and I could make instructions for that pretty easily. But would it still have the same charm, and would anyone want that version? I'm not sure. 

So, I haven't really planned to do it. But if a lot of people want them, and would be ok with a version with less motion, let me know and I can look into it. I can't/won't make any promises, but I'd at the very least consider it and see what it would take to get something good out.

I think if you put together a Youtube video demonstrating how to mess with the side-sway, people would get it down. Most AFOLs understand that there is a certain amount of finesse necessary to get things right when it comes to detailed models, and if you simply showed off the process of how you wiggle things into place, there would be no need to convey that via instructions.

If that sounds like too much, I understand entirely. But I figured I would throw it out there.

[Roadmonkeytj]

Love this ... Really would buy this over the disney train! Well done sir!

[Modeltrainman]

This is amazing! I like that you got a moving smokestack on him, something I couldn't do in mine.