Model railway turntable automatic Indexing

Hello all,

I have posted a few times (here ) about a little model train control application I put together with Nodered, ESP8266, Tasmota, MQTT and a PI4.

It is designed to control vintage (30++ year old) Märklin accessories without altering them.

With this app I can control a 60 year old turntable (that's the round thing that turns a locomotive around on a revolving bridge :wink: ). In its original state, a press on a control box will move the bridge to the next position. This has to be repeated as many time as required to get to the desired destination. The app does this bit automatically. This was all timer based: for each position on the turntable, I had to configure the travel time to the next position clockwise and anticlockwise, and the flow would then wait accordingly before triggering the next movement. This could easily get out of sync.

So I invested in a current sensor, and changed the flow to use load information instead of timers to move the bridge, The flow issues a move command when the current load drops under a set threshold.

E Presto! Motor stops, load goes down, next move command sent, no more stopping short of the final destination.

There is a short video if you are interested: here
There is also playlist with all sort of "projects" I have been or am currently working on here


There's something special about model railways. :grinning:

If only we could bring this turntable (Curzon St, Birmingham) back to life too, with two or three early locos to shuffle, and controlled of course by a British Raspberry and Node-red.


Would make for an interesting and unique café/restaurant! With people in carriages being shuffled about as they ate. :grinning:

Though I'm not sure how nice an area Curzon St is at the moment? I'm from Birmingham originally but haven't lived there now for over 20 years. Haven't been to the city centre for possibly 15 years.

  1. it's in Birmingham! :slight_smile: A post modernist paradise most likely...
  2. it's looks like a bomb site at the moment according to the wider version of @jbudd 's picture on google earth

Raspberry PI and Nodered would be the least difficult to achieve by the looks of it

Sorry, I wasn't clear enough - I'm from Birmingham so I know where it is, I just don't know how nice it is at the moment. Looking at the satellite - poor old Birmingham, still suffering by the looks of it - as you say, more like the aftermath of a war when looking from above!

Still, that could be a nice area if done properly so my suggestion stands - anyone know the mayor? :rofl:

You were clear enough...

The exclamation mark after Birmingham, reinforced by a smily, was meant as a silent "what do you expect?" :slight_smile:

Ah, obviously too subtle from me - but then I am from Birmingham so what do you expect! Though I think of myself as an adopted Yorkshire-man now, safely ensconced in Sheffield. :smiling_face_with_three_hearts:

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