Automatic train uncoupler?

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michaeljoe

Well-Known Member
While gathering the materials and information I need for my HO layout, I'm wondering, what to do if I want to uncouple train cars automatically.
I do not have or want a ....DCC train system... at this time.
In other words, if I back the trains up into a train yard and want to uncouple two or three cars without doing it by hand.
Is there a certain piece of track system, like a remote turnoff?
And I'm pretty sure that the cars need magnet couplers.

I hope my description makes sense. Remember I'm new at this.
I guess I should have done more research, but I'm spending, 8..10..or more hours every day including weekends redoing/modeling our kitchen.

....Thanks..... so much I really appreciate the information and education that everyone has given me.
 
There are various uncoupling devices available for use with the Kadee knuckle coupler. It depends on your needs.
If you're using the hook horn coupler, someone else may comment on that.
I don't like to have the uncoupling ramps on my track because of the appearance.
I use uncoupling picks instead. They are basically a skinny stem of wood or plastic that can be inserted into the joined coupler from above and twisted which opens the coupler. They can also be used to flick the little simulated hose to one side which opens that coupler as well.
There are also magnetic uncouplers which fit down between the rolling stock on each side of the coupler to pull the two simulated hoses outward which opens the coupler.

1731585193447.png


1731585238837.png
 


Mopac Junkie said:
exact

exactly. I have over 30 KaDee magnets of various types on my layout in strategic locations.
Click to expand...
Do they work as designed? When I redo my layout, I was thinking of throwing a few onto it. The delayed version allows pushing the car after uncoupling?
 
Is there a reason that a simple circular rare earth magnet (quite small) be placed between the ties? Easier to hide, pretty powerful …..
 
michaeljoe said:
I'm wondering, what to do if I want to uncouple train cars automatically.
In other words, if I back the trains up into a train yard and want to uncouple two or three cars without doing it by hand.
Is there a certain piece of track system, like a remote turnoff?
Click to expand...
That is exactly what the Kadee delayed uncoupling system is for. Yes, they work if you keep all your couplers in perfect alignment and springiness.

Kadee makes two types of stationary, and one electromagnet type to match the specific situation on the layout.

We used to use them at the club and for the most part they worked just fine. Eventually we ripped them all out and went to the manual picks. As we were an operationally oriented layout the majority felt picks were more like switching in real life.

michaeljoe said:
And I'm pretty sure that the cars need magnet couplers.
Click to expand...
Well not magnet couplers but they have to have a steel trip pin on the knuckle. Almost every coupler on new equipment out there has them.
 


D&J RailRoad said:
There are various uncoupling devices available for use with the Kadee knuckle coupler. It depends on your needs.
If you're using the hook horn coupler, someone else may comment on that.
I don't like to have the uncoupling ramps on my track because of the appearance.
I use uncoupling picks instead. They are basically a skinny stem of wood or plastic that can be inserted into the joined coupler from above and twisted which opens the coupler. They can also be used to flick the little simulated hose to one side which opens that coupler as well.
There are also magnetic uncouplers which fit down between the rolling stock on each side of the coupler to pull the two simulated hoses outward which opens the coupler.



View attachment 204475
Click to expand...
Thanks, I don't understand the picture above.
Is this something you made yourself?

looks like you press down with your finger and the mechanism lifts up to uncouple the train.
Is this how it works?
 
This design is quite simple. It's solid plastic with two magnets glued in place on the two tongs. Nothing moves on it.
This is positioned between the two cars that are on the track. The magnets attract the metal hose that extends below the knuckles and the coupler opens up.


1731757374037.png
 
I used an under the track magnet and found that it sometimes would uncouple cars unintentionally.

If I were to go that route, I would advise a wired uncoupler that can be de-activated.

I currently do not have or plan to install a magnet under my track. I manually uncouple.


Dave LASM
 
Myrastation said:
Is there a reason that a simple circular rare earth magnet (quite small) be placed between the ties? Easier to hide, pretty powerful …..
Click to expand...
Yes.
The small round magnet doesn't have enough area differential to pull the trip pins away from each other. A magnet would need to be oval shaped at least, so it's long enough the two poles will act in opposite directions.
 
D&J RailRoad said:
This design is quite simple. It's solid plastic with two magnets glued in place on the two tongs. Nothing moves on it.
This is positioned between the two cars that are on the track. The magnets attract the metal hose that extends below the knuckles and the coupler opens up.


View attachment 204715
Click to expand...
Do you still require full slack between the couplers for that to work? And for HO use, I would assume the top tab where you grasp it would need to be long enough so the that your fingers clear the top of the car?
 
bnsf971 said:
Yes.
The small round magnet doesn't have enough area differential to pull the trip pins away from each other. A magnet would need to be oval shaped at least, so it's long enough the two poles will act in opposite directions.
Click to expand...
Interesting, OK. I buy rare Earths at Lee Valley and they come in many different sizes, I use the 1/2” ones to hang carving tools on the bench so very strong.

I will try the 3/8” or 1/2” and see what happens.
 
On one of my first N-scale layouts, I used neodymium (rare earth) magnets. I had to experiment with magnet size, as the larger they are, the more magnetic force they exert. For Atlas code 80 N-scale track, I went with 1/4" dia. x 1/8" thick magnets. The thickness fits perfectly in 1/8" thick cork roadbed. One pair of magnets was used at each uncoupling location, and mounted 3/8" center-to-center in the cork roadbed (or one magnet directly under each rail). No messing around, they uncouple with authority without being too overwhelming.

For HO scale, one probably wouldn't want to go much bigger on the magnets, because the distance between the bottom of the ties and the top of rails isn't a whole lot greater than for N-scale. And going slightly wider between the two magnets (maybe 1/2" to 5/8" center-to-center) would probably still allow proper uncoupling. Once again, I'm just guessing here for HO scale, as I have never performed any tests for this scale. So some testing will undoubtedly be necessary.

And a surprise extra bonus for the N-scale crowd..................... You can mount a pair of magnets in a properly sized piece of cork roadbed (per my previous N-scale description), then glue the cork up underneath of Kato Unitrack, Bachmann E-Z Track, Atlas True Track, etc. The result is instant magnetic uncoupling for built-in plastic roadbed users!!! And once a proper magnet size has been selected for HO scale, this idea should work for the HO guys!

Hope my findings in N-scale give a good starting point for HO-scale. :)👍
 


Mixed Freight said:
On one of my first N-scale layouts, I used neodymium (rare earth) magnets. I had to experiment with magnet size, as the larger they are, the more magnetic force they exert. For Atlas code 80 N-scale track, I went with 1/4" dia. x 1/8" thick magnets. The thickness fits perfectly in 1/8" thick cork roadbed. One pair of magnets was used at each uncoupling location, and mounted 3/8" center-to-center in the cork roadbed (or one magnet directly under each rail). No messing around, they uncouple with authority without being too overwhelming.

For HO scale, one probably wouldn't want to go much bigger on the magnets, because the distance between the bottom of the ties and the top of rails isn't a whole lot greater than for N-scale. And going slightly wider between the two magnets (maybe 1/2" to 5/8" center-to-center) would probably still allow proper uncoupling. Once again, I'm just guessing here for HO scale, as I have never performed any tests for this scale. So some testing will undoubtedly be necessary.

And a surprise extra bonus for the N-scale crowd..................... You can mount a pair of magnets in a properly sized piece of cork roadbed (per my previous N-scale description), then glue the cork up underneath of Kato Unitrack, Bachmann E-Z Track, Atlas True Track, etc. The result is instant magnetic uncoupling for built-in plastic roadbed users!!! And once a proper magnet size has been selected for HO scale, this idea should work for the HO guys!

Hope my findings in N-scale give a good starting point for HO-scale. :)👍
Click to expand...
This is what I was expecting would be the result, thank you.


I have a stack of rare earth magnets, I buy them by the dozens at Lee Valley, so ….
 
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