I would like to automate throwing a turnout based on the direction a train approaches from.
On my previous layout I had the same configuration and I just let the turnout points ‘float’ freely move based on the direction the train came from. I thought this was going to be temporary but it actually worked very reliably and it allowed unattended continuous running of a train all the way from the lower return loop up to/through the upper return loop and then back down through the lower return loop, repeat ad nauseum.
The issue with that solution is that when the train returned from the upper return loop it would follow the path through the lower return loop where it had come from. After traversing the lower return loop the lead locomotive would ‘move’ the free floating points to throw the turnout to whichever side it was coming from. And then when it returned from the upper return loop it would follow that path back through the lower return loop. Basically it would alternate the direction/path the train would take through the lower return loop each time it made the entire layout loop.
As a side note, the upper return loop was/will be a true return loop with a PSX-AR that would automatically throw the turnout to the required direction. This was all done in hidden track so an observer would just see the train enter a tunnel and then a minute or so later it would come back out the same tunnel/track.
The lower level return ‘loop’ has about 125 ft of double track mainline, where one track is East bound (headed into the lower return loop) and the other track is West/North bound (leaving the lower return loop). The turnout I would like to automate is what controls this.
The turnout/points in question is on a double slip switch (which should not matter).
If a train approaches from one direction (RED) I want the points for position RED and if a train approaches from GREEN I want the points aligned for position GREEN.
So basically I need to detect a train and direction of travel for two sections of track and to throw a turnout (Tortoise) accordingly.
Is there a commercially available device that I can use for this? If not, are there plans/schematic for this sort of device?
what about making it a spring switch? use a light gauge wire to hold the points in one direction but allow a train coming from the opposite diverging track to push the points when it moves thru the switch
Thanks, that might work and it would be an easy experiment.
My only concern would be hundreds of axles/wheels of much lighter freight cars for each train would also have to be 100% dead nuts reliable pushing against the spring. With the current implementation the heavy locomotives throw the points and the rest of the train doesn’t have to worry.
Well, one easy solution would be to convert to O gauge–most O gauge turnouts are already non-derailing. But I suppose that you don’t want to do that. In order to have it reset electrically (provided that the spring switch doesn’t work out), you would need three detection systems of your choice (I’d recommend insulated third rail, but this is HO we’re dealing with… sigh). Place one on each leg of the turnout, and also a full train length from the beginning of the turnout. Wire the ones on the turnout legs to the respective routes, and wire the one a train length away to throw the turnout in the direction of your preference.
My lightest spring wire is 0.025 and I was not close to getting it to work. I tried 4 or 5 correctly weighted box cars and gondolas and they all derailed when they tried to push through the points. Any lighter tension and the points would not return. I think the issue is related to it being a double slip switch and having double the points to slide/move.
I am still looking for device/mechanism to detect and ‘signal’ for when trains approaching from a specific direction.
Except I value my time at $100/hr and it would take me probably 5-6 hours to get the pieces/parts, get them assembled, debugged, and working. So $40 is totally worth it.
True, I use Kato Unitrack and their No.6 manual and electric switches (if you set them to be non-power routing) work as spring switches quite nicely. I’ve had a little trouble with some steam engines pilot wheels, but all my diesels and all freight and passenger cars go through without a hitch.
