DCC (and other digital tech) for LEGO trains

[McWaffel]

As per the suggestion of @icemorons I’m opening this new thread so we don’t need to talk about DCC in the 2022 trains thread. I think it’s an interesting topic, especially given that there are no out-of-the-box solutions available (yet), for LEGO trains to be fitted with DCC.

To start off the thread: I‘m planning to retrofit my trains with DCC as soon as FxBricks releases their DCC-ready motors. In the process I will also fit LEDs into my engines and cars.

In the meantime I thought about how to use my PF train motor on my 9V layout. The plan is as follows: as soon as I can get my hands on an old, burnt-out 9V motor, I will remove the motor and use it as a power-pickup. Then I’ll buy a PF extension cable as well as an old 9V extension cable, and build a 9V-PF adapter cable out of it. This way I can use the 9V motor‘s output to power the DC motor in the PF bogie. And this will then also allow me to easily retrofit a DCC decoder in between, as soon as I start to move to DCC entirely.

Edited January 31, 2022 by McWaffel
adjusted title to include more tech than just DCC

[Sunil766]

3 hours ago, McWaffel said:

Then I’ll buy a PF extension cable as well as an old 9V extension cable, and build a 9V-PF adapter cable out of it.

That's 8886 isn't it? That would probably be more expensive though. 

I'd personally be interested in the basics. I only run regular 9v and all those esp*** numbers are very confusing. I'd need a basics tutorial to understand how complicated it would be to start using that stuff - to get the benefit of running more than 1 train per loop. 

[Toastie]

@McWaffel

This is not directly about DCC, but about modifying a 9V motor as power pickup AND DC motor controlled by a PF receiver, which is in turn powered by the 8878 LiPo, which is in turn charged on the fly by the motor pickups. As the 9V train motor handles PWM very well without any issues since 1 1/2 decades (surely not every day(!!!) but every now and then), I don't see why you want to wait for DCC (DC) motors - other than that they are different from regular DC motors of course!

This is a "real" train operating in that principle:

BTW, 7938 has been retrofitted to PoweredUp (City Hub) two years ago => removed the battery compartment of the hub (cf. third pinned topic in the TrainTech forum), hooked that one up to 8878, which is charged via the 9V motor pickups. The City hub runs the 9V motor in the pickup  - all works well.

Will be fun to see your DCC solution!!!

Best,
Thorsten

 

45 minutes ago, Sunil766 said:

I'd need a basics tutorial to understand how complicated it would be to start using that stuff - to get the benefit of running more than 1 train per loop.

@Sunil766 As we are in @McWaffel's DDC thread: You want to go DCC or are you not yet sure, which system to use?

The confusing ESP*** numbers in the other thread were mostly related to wireless control (WiFi or Bluetooth Low Energy, BLE, which is what TLG uses for PoweredUp components equipped trains - and all their other current remote controlled sets)

Best,
Thorsten 

[McWaffel]

1 hour ago, Sunil766 said:

That's 8886 isn't it? That would probably be more expensive though. 

Oh, damn I didn’t realize that extension chord is 9V-compliant. I need to check how much each option would cost.

@Toastie you can talk about the ESP stuff here too, I just created this thread specifically so we can talk about all sorts of tech, that we were doing in the 2022 trains topic before.

 

52 minutes ago, Toastie said:

I don't see why you want to wait for DCC (DC) motors - other than that they are different from regular DC motors of course!

I simply don’t want to ruin pristine, working 9V motors ¯\_(ツ)_/¯ 

I‘m just waiting for FxBricks to release theirs, because they supposedly will allow a split between pickup and drive power, so people can put DCC decoders in between. if I wanted to do that with my 9V motors, I would have to basically permanently modify them, which I don’t want to do

[Toastie]

19 minutes ago, McWaffel said:

you can talk about the ESP stuff here too

Very cool, thank you!!!

20 minutes ago, McWaffel said:

I would have to basically permanently modify them, which I don’t want to do

Absolutely understandable. I am also waiting for their pickups, because then one can get the juice on a much smaller "scale"

Thanks, and all the best,
Thorsten

[JopieK]

Nice topic. I experimented with DCC in the past (with an Intellibox). I must say it has been a while and since then I learned a lot about microcontrollers etc.

[Ondra]

There needs to be literally only one solution to this.

Motorized bogie(Like classic 9v motor but modern motor inside) with DCC inside. Everything will be solved for me... Yeah and tracks.

 

I will pay if this will be real, these battery thingy trains gets me off totally....

 

I have more fun with static three parts DMU made from parts from two 60197 sets. Just sitting on shelf. And some scenery around...

If there will be 9V around, that train will be riding endlessly by just changing one bogie.

 

[XG BC]

i am waiting for fxtracks motors aswell. will go dcc when they become available.

[Toastie]

27 minutes ago, XG BC said:

will go dcc when they become available.

Any thoughts on wireless as well? The principle is the same: There is a central brain (the Client, representing many clients = trains, e.g. a RPi or ESP***) and the servers (= individual trains with a brain = ESP*** or PUb hubs) - which is more or less identical to DCC, but differently realized.

DCC needs all metal track, wireless some metal track for recharging (on the fly - whenever on metal track, the motors run off from metal power, when on plastic track, they run off from the LiPo/NiMHs or whatever rechargeable you prefer). With a mixed metal (80%) all plastic (20%) track the net outcome is charging, at least with the load I was pulling back then, see above.

The other thing is, the double cross-over (e.g. from BB, with some tinkering) works, wyes work, back loops work ... all plastic stuff from X and Y works ...

But: Just my take!

All the best,

Thorsten

[dr_spock]

I think you can build a wireless DCC base station with an Arduino.  DCC+ or something like that on github.  Run JMRI.

As for wyes and loop backs, there are ways to make them work. You may have to put in a gap in the track and/or have some intelligent electrical switching device.  I should go through my collection of old Model Railroader magazines.  They run articles on how to implement DCC from time to time.

[Pendra37]

Is it still considered Lego? Normally Lego is supposed to be stuff that you can do using original Lego parts. Here we are talking about 3rd party off the shelf solutions with IR and BLE. Also low level DIY options. Is that Lego?

I mean If you take a stock VW Beetle, completely gut the internals and rebuild it with all aftermarket tuning parts, can you still call the result a stock VW Beetle? The side paneling may be stock VW, but the important parts are not. Same here, you take a Lego product, completely gut it and rebuild it around aftermarket tuning part, will that be still Lego? The side paneling is Lego, but the important parts are not.

If I make a build where, at one step, you you would need to glue two plates back to back is that still a Lego build?      

I find these questions kinda important because if the rules are so that you can use whatever you want, then the logical solution would be to use O gauge model rails and locos, remove the superstructure and bolt Lego plates onto the chassis. Then take a readymade DCC solution and be done with it. Simple, easy, minimal hassle. Everything is bog standard and still looks Lego. I mean Marklin did it. H0 rails, H0 chassis with Lego compatible plates so you can build your Lego (4 wide) superstructure.

So where is the end? What is accepted within the boundaries of "Lego train" and what is too far?

So if I 3D printed some bricks that can interlock with Lego and place motors, driving electronics and battery boxes inside, would you accept that as a viable option? 

Edited January 31, 2022 by Pendra37

[JWBDolphins]

3 hours ago, Pendra37 said:

Is it still considered Lego?

Great question!  I think probably the Rightest of the right answers is, "its your hobby so whatever you want that answer to be is the right answer."  Now if you are a reseller of LEGO, etc, that might be a different answer.  But your question is an intriguing one and I think about it a lot!  

The only answer I can give is where I draw the line.  Generally, if LEGO does Not supply an option for what I need, then I improvise and make my own.  Once they do come out with whatever part I want, I swap to it.  Also, generically, if I'm making instructions for a model (I like to do that for myself so I don't forget what I did!), I'll make the instructions with a "pure" LEGO build, and then a "oh, by the way, you can get around this problem by x" option.

A couple examples.  I built an engine around a Power Functions train motor and had the sides go down flush against the outside edge of the wheels.  LEGO provides a 6L axle but that is too long.  The pure LEGO option is put a 3L axle on one wheel that the motor will catch on one side, and a 2L axle on the opposite wheel.  The sides will keep the wheels "trapped" so the won't fly out.  The motor has the catch on the other end cattycorner from the first end so you reverse the 2L and 3L axles.  I didn't like that solution - I wanted 4 wheel drive, so my option was to Cut a 6L axle to fit.  If LEGO comes out with a new size axle that fits, I will just use it.

Last example.  I came to LEGO trains right after the 9V era ended, but I picked up a BNSF engine and want to run it.  Power Functions doesn't provide a good solution because the battery box is too wide - you need to either have a big gray blob in the middle of the engine or try to color match stickers.  My solution, use a much smaller LiPo battery (works great by the way.)  (One caveat, Make Sure you fully research LiPo batteries before going that route.)  Now, if I want to connect that LiPo to a PF Receiver - I don't want to modify the receiver at all - so my solution was to buy Power Function Extension cables, cut them in half, and solder on common connectors that will connect to the LiPo.  In my case I chose XT30; they are a little big but very easy to solder and can handle a Lot of amps - more than LEGO will be a problem with.  Yes, I killed a LEGO part (extension cable) but I fixed a problem LEGO didn't give me a solution for.  In reality, I don't use PF or PU, but that's a discussion for later and really relates to the "and other digital tech" topic.    Since PF is now dead, LEGO has moved to Powered Up which is Great, but they did NOT give us a backwards compatibility mechanism.  LEGO Orphaned all the PF motors, lights, etc.  My solution - wait until a Powered Up extension cable comes out, cut it, and add XT30 connectors to it.  If they Don't come out with a Powered Up extension cable, I'm very close to buying a Powered Up LED and lopping off that connector and adding an XT30, as I don't really use PU.  Or, more realistically, since the PU LEDs increased in price quite a bit over PF, just come up with my own Much cheaper LED option.  Again - fill a need that LEGO doesn't really provide for me.

I hope this didn't get too off topic, but that's pretty much where I draw the line.

[XG BC]

7 hours ago, Toastie said:

Any thoughts on wireless as well? The principle is the same: There is a central brain (the Client, representing many clients = trains, e.g. a RPi or ESP***) and the servers (= individual trains with a brain = ESP*** or PUb hubs) - which is more or less identical to DCC, but differently realized.

DCC needs all metal track, wireless some metal track for recharging (on the fly - whenever on metal track, the motors run off from metal power, when on plastic track, they run off from the LiPo/NiMHs or whatever rechargeable you prefer). With a mixed metal (80%) all plastic (20%) track the net outcome is charging, at least with the load I was pulling back then, see above.

The other thing is, the double cross-over (e.g. from BB, with some tinkering) works, wyes work, back loops work ... all plastic stuff from X and Y works ...

But: Just my take!

All the best,

Thorsten

i prefer all dcc i dont like batteries and having to integrate them into a smaller locomotive which is the type i usually build and can live with the trade offs but to each their own i guess

Edited February 1, 2022 by XG BC

[McWaffel]

7 hours ago, Pendra37 said:

So where is the end? What is accepted within the boundaries of "Lego train" and what is too far?

To be frank: who cares? 
this isn’t a competition. We’re just here to have fun and enjoy a hobby. You want to build LEGO on top of O-gauge trains? Cool, do it. You want to modify 9V motors to do DCC? Also cool. 
 

I don’t think anybody should draw lines anywhere in that regard. Everyone can do whatever they want. You need to know for yourself what is fun for you and what isn’t. Personally I want to use as much LEGO as possible, but ultimately it doesn’t matter. Even 3rd party LEGO-compatible stuff counts in as „LEGO“ for me in that regard

[Toastie]

2 hours ago, McWaffel said:

Personally I want to use as much LEGO as possible, but ultimately it doesn’t matter. Even 3rd party LEGO-compatible stuff counts in as „LEGO“ for me in that regard

Same here - exactly that. That is my approach as well.

However, there are also the "Forum Rules". Clone brick-built carriages and trains (never even closely offered by TLG) usually get beamed into the Community forum. There is already a BlueBrixx thread, where the quality and issues with their stuff is discussed. Unfortunately, I'd say, because it really is interesting. I am not talking about bluntly copied stuff (or even remotely copied) - but BB originals (they call "specials", I believe but don't know).

But other than that: Very nice to have these and other topics related to train right here, where they belong.

Best
Thorsten

[Pendra37]

4 hours ago, McWaffel said:

To be frank: who cares? 
this isn’t a competition. We’re just here to have fun and enjoy a hobby. You want to build LEGO on top of O-gauge trains? Cool, do it. You want to modify 9V motors to do DCC? Also cool. 
 

I don’t think anybody should draw lines anywhere in that regard. Everyone can do whatever they want. You need to know for yourself what is fun for you and what isn’t. Personally I want to use as much LEGO as possible, but ultimately it doesn’t matter. Even 3rd party LEGO-compatible stuff counts in as „LEGO“ for me in that regard

One thing is what Toastie said. This forum is mostly for genuine Lego stuff. I suspect this topic is pushing it a bit because we set out to do something that is flat out not possible using real Lego parts. This thread will inevitably devolve into discussions of various non Lego parts and solutions. I don't know how well that will sit with the moderators. 

The other thing is more philosophical. Apart from being kid's toy and stuff, I consider Lego as a 3D puzzle game or a logic game. You have a predefined set of parts and something you want to create from said parts. You need to figure out which part goes where using what technique. The limited set of parts are one of the challenges of the system because you need to work around that limitation to get good looking results. The better you are at it, the better your MOCs are and the more praise you should get. However, from this point of view, using non Lego parts is kinda like cheating. Instead of finding some nifty workaround and technique to achieve your goal, you cheat and invent non existant parts and/or use illegal build techniques. If you build this DCC and someone says, "Wow, how did you build this from Lego", you need to say that, "No, this is not Lego, it has some Lego elements but you can't make this using all Lego parts". This defeats the whole idea of Lego MOCs.

Still, the idea is interesting and you are absolutely right that this is your hobby and you should do your hobby the way you like it. This is not a Lego religion or something where you get chastised if you deviate from the norm and use the unholy bricks of the devil. 

Edited February 1, 2022 by Pendra37

[McWaffel]

If TLG wanted us to be able to use LEGO technology, they would integrate mindstorms/NXT or whatever their current lineup is called, into trains.

They don’t, so we have to get third party stuff. Same with LEDs, by the way. And no, the PF LEDs they used to sell don’t count. Two LEDs with a cable for that price was criminal.

Clearly we have no choice other than to use 3rd party equipment. And moreover, LEGO trains is arguably the one theme that uses the most 3rd party elements. Track, wheels, motors, energy storage etc…

[Pendra37]

The problem with the Mindstorms/NXT is that the central unit is ****** enormous. You can get actual Win10 PCs that are smaller than that thing. I don't think you could hide that in a train effectively. Smaller issues are that the sensors are also on the way too big side. Finally, the price tag is like the size, crazy huge. Anyhow, if you don't mind that weird boxes are sticking out of your trains and it is also not a problem to pay a few thousand USDs for multiple NXT bricks and sensors, you could construct a reasonable DCC system.    

[McWaffel]

That’s exactly the problem. NXT is way overpriced (not that LEGO isn’t overpriced generally) and is total garbage hardware, and doesn’t even integrate to the trains properly. It’s not even remotely a reasonable option. I‘m sure once FxBricks gets their motors and power supplies out, they have a real chance at dominating the LEGO train market, if they manage to get their product more visibility at various reseller stores.

so yeah I agree with your NXT arguments 

[dr_spock]

NXT/EV3/Spike can be used to control track side accessories. Boost could be turned into a blocky locomotive 

Adding DCC to LEGO has been done by AFOLs before.  Many years ago Michael Gale had LEGO train with DCC modules installed running on 9V track and motors.  I think the challenge is wiring those small DCC modules.  LEGO locomotives don't come with DCC sockets.  No easy plug and play or pray.

If you can solder, you can make an adapter board that has a DCC socket, PF/PU connectors, speaker connectors, etc.  Soldering is one of those handy dandy life skills.

 

 

[Toastie]

5 hours ago, McWaffel said:

they have a real chance at dominating the LEGO train market,

yes, but depends on what the "LEGO train market" means. I have a feeling that although TLGs train sets do not appeal to "many" here on this forum and elsewhere, that this particular "many" represents only a tiny fraction of the sum of moms and dads, grandparents and others happily buying TLGs current trains sets. These sets are quite large (the box that is ) and since the store's shelf-space as well as set order or box appearance on the shelves is definitely optimized by some folks at TLG who hold an M.Sc. in "Finance of Shelf-Space Optimization & Accounting", they must sell; otherwise they'd be kicked out as soon as red numbers appear on some Excel sheets in Billund.

So yes, FX will dominate when they succeed, but only "the LEGO train market for bold LEGO train enthusiast with deep pockets". Which is perfectly fine with me, I wish them all success!!!

All the best,
Thorsten

[Toastie]

5 hours ago, McWaffel said:

NXT is way overpriced (not that LEGO isn’t overpriced generally) and is total garbage hardware

Overpriced, yes - but total garbage hardware - no.

In contrast, these are nicely engineered embedded systems, have memory large enough to "never" be filled with handmade machine code - even a C-program will have some substantial numbers of code lines before that memory is full. Sound is OK, display sucks when getting older, 4 inputs, 3 outputs, I2C bus (and thus open to the World of Peripherals ), BT (over serial), USB ... no not that bad, I'd say. Definitely not for a train, but maybe for controlling an entire train layout. And 16 years old. NXT's are currently rather cheap on BL. The EV3 came later (also not good for trains, but good for controlling three train layouts in parallel ) - and now we got PUp. The City hub is performance- and size-wise undoubtedly attractive for trains - but the battery sucks, as discussed. We are THAT close, but I guess it simply will not happen - because the metal track is gone. Good we have FX.

In other words: Fire up the soldering iron. , as @dr_spock said!

Best,
Thorsten   

[legotownlinz]

6 hours ago, McWaffel said:

I‘m sure once FxBricks gets their motors and power supplies out, they have a real chance at dominating the LEGO train market, if they manage to get their product more visibility at various reseller stores.

This is unlikely to happen for several reasons like

• pricing
• less track elements compared to the 3D-printing competition
• less motors and wheels
• complexity of DCC
• dependency on one manufacturer
• huge number of existing layouts that cannot be upgraded

DCC is a good choice for anyone interested in the technology. But the majority who occasionally plays with trains is better off with Powered Up.

[XG BC]

2 hours ago, legotownlinz said:

This is unlikely to happen for several reasons like

• pricing
• less track elements compared to the 3D-printing competition
• less motors and wheels
• complexity of DCC
• dependency on one manufacturer
• huge number of existing layouts that cannot be upgraded

DCC is a good choice for anyone interested in the technology. But the majority who occasionally plays with trains is better off with Powered Up.

the thing is there isnt much of a train market to begin with but thats another story. for the casual i play with city trains type the powered up thing is ideal. just pop in the batteries and go. but if you want to build smaller locos or really get into it (atleast for me) powered up just doesnt cut it unfortunately. too large, eats batteries, too little official ways of expanding (yes i know pybricks exists), just not for me. i and many others here are not the target audience for such products. these are designed with children in mind at their core. fxbricks fxtracks is however designed with us, the afols and enthusiasts in mind and i do think it will be quite popular as the requirements for us are totally different.

[McWaffel]

I keep hearing this „trains is a niche market“ thing, but have yet to see any actual proof of it. When I was a kid, everyone and their moms had a LEGO train. Like, literally 5/6 of my closest childhood friends had a 9V train set. 

But I digress, this is tech talk after all. DCC isn’t really difficult to set up either. Most model train starter packs that come with DCC are super kid-friendly. You essentially start off with a central controller, and an app and that’s really it. Couple of cables and you’re good to go. You can buy trains equipped with decoders off the shelf. 
I don’t necessarily think we need that level of convince in the LEGO world for DCC (although it would be very nice), but I would already be happy with having a motor with split power pickup and drive train. If I can also buy a cable for it so I don’t need to solder anything to metal parts that rest on plastic housings, I‘m golden.