Hang on a minute...

Yes, you may have spotted that although this works, it only works in the sense of decoupling, you can't go back and reattach the disconnected wagon.

So the time machine plans have been put on the back burner, again...

As I want this to be a track based solution, I didn’t want to start adding bits to engines or wagons, and so I guess I’ll have to stare at the track again.

What about if I added some type of lock that keeps the decoupler in place when not required ? 



Now I know there is very little height to play with, so I concluded that the only way would be to raise the track by a couple of plates.  This is the bare minimum to slide a lock underneath the track.  Ok, that’s not too bad.  I also added one plate on another track section before the decoupler, so there is more of a gentle incline and a few more 2 plates on track sections after.  You could of course leave that as a sharper incline to allow the disconnected wagons to roll down the siding.

The lock was straight forward, 2x (2 x 6 tiles) and a 2 x 2 plate to hold it together.  This has just the right clearance to slide under the track, which stops the decoupler from pivoting into the gap.  Well, that works, now what ?

decoupler with lock on baseplate 

Another test and a version built on a baseplate (some layouts have their track built on them), which meant that I needed to add some tiles on the baseplate in order for the lock to slide along.

Now, I can get back to that flux thing.......