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Discussion Starter · #1 ·
Hi all, I'm hoping you guys can perhaps shed some collective wisdom on something for me. Before I start I know there's a hundred and one threads on this topic but they don't seem to answer my problem. I'm using hornby tension lock couplers, and on the majority of stock I have these are the smaller coupler (like bachmanns) that fit into the pocket, and I'm very happy with them. My problem is with the uncoupling ramps: they're big, restricted in the positions they can be placed, cause premature release if the loco goes too slow over them and the edges quite often catch on the loco - this is annoying. I have no space under the board to motorise them, and I do not want to faff about with installing kadee couplers, as much as people insist that it's the only way to go for "true" coupling: as I said above I like the tension lock and the looks don't concern me. I have read somewhere on here about using magnets and staples, but that stated it only works on bachmann couplers due to the material used on hornbys becoming magnetised.
Therefore does anyone have any recommendations as to how to achieve a better uncoupling device that could be placed on say curves, or at least not 20 miles away from where I actually want it, and that doesn't catch on the bottom of the locos? Or does anyone have any experience of using the hornby couplers and magnets? I was contemplating using a piece of small clear plastic with the ends under the sleepers (akin to the black uncouplers) which would remove the obvious frame issues of the original, but which I suspect would still release stock too soon as it went over (i.e. when not stopped). Any help would be gratefully appreciated as it's spoiling my fun at the moment.

Dave
 

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Discussion Starter · #3 ·
Cheers John, that's the type of thing I had in mind but with clear plastic but I'm still not sure that it isn't going to uncouple the rolling stock when I don't want it to. It would solve the snagging problem though. I might have a play with something later when I get back from the beach if it's not too late. Has anyone any experience with this who could shed some light on the pro's /cons? or any other methods to contemplate? I guess it's a fairly personalised decision uncoupling but any advice appreciated.

Dave
 

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I am another who likes the miniature tension lock for steam era 4 wheel wagons. This is mainly because they give a loose coupled effect; they can be very easily repositioned for as close coupling as your curve radius permits: anything over 24" radius allows wagons to buffer up when pushed, a very nice effect, and the 'bumper bar' positively prevents any buffer locking, and they then pull out to a realistic 2mm gap between buffer heads. But I wanted hands free uncoupling at least as good as Kadee.

I have tried clear plastic bows for uncoupling, but they just didn't cut it with miniature tension locks and realistic operational speeds. Difficult to run a train of a couple of dozen goods wagons over one at a scale 20mph or slower without an unwanted uncouple. The problems arise because the latch action of the miniature coupler has a far smaller area engaged than the old 'volvo bumper' device, wagons are now very free running, and the locos give really good slow speed control, so you can run slowly. Quite frequently the springiness of the ramp pushes a wagon forward as it goes over the highest point, and the couplers unlatch in the small slack created. As for uncoupling on curves, you need a very large radius curve to accomodate the uncoupler. There is an added difficulty that many models now have realistic low hanging fixed detail, and will ground or snag on a bow high enough to do the uncoupling job, much as you have noticed with the sprung proprietary ramps. Finally, with the coupler tail being metal of fairly small section, the bows don't last that long if the layout is intensively operated, the coupler tails scoring through the plastic until one cuts through enough and catches; biggo derailment. That last led to me abandoning the whole idea, now I was stuck...

But then came the Brian Kirby mod to the Bachmann tension lock: it has proven simple and effective, easy to add to stock, and very reliable. Here I 'got lucky', it had become obvious that the best coupling reliability was obtained by standardising on one make of miniature tension locks. I chose Bachmann simply through having more of theirs than any other makers ( thanks to that 16T mineral) so was all set. A regular Kadee permanent magnet uncoupler will activate the modified coupler which is truly handy as I use Kadee for coaches, ( if required smaller magnets can be used on curves, you cannot have such close coupling though). If the train is sharply decelerated while crossing a permanent magnet there is a chance of an unwanted uncouple, (and the same can happen with Kadee). As a result I plan on fitting electromagnet uncouplers on running lines, keeping permanent magnet for sidings only.
 

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John,

You are quite right. I tried this idea some tima ago and found it worked very well. Indeed, every other system is both complicated and expensive. Some people might say that this is bordering on the "cheap and nasty", but I say "cheap and simple". You can also add "reliable". No electrics, no magnets.
Brilliant.

Dave,

The problem of uncoupling when you don't want it to is also simply explained. As long as the train/vehicles are moving, and the couplings are in "tension", when passing over the ramp, then uncoupling will not take place. It will only happen when you stop the vehicles with the couplings over the ramp. The tesion is released, and the upwards pressure of the ramp will raise the dropper arms on the couplings. You can then just pull away, leaving the other vehicles standing.

The only negative side to this system is that once you have uncoupled something, you cannot then push it further without it re-coupling.

gresley
 

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Dave

The Kirby uncoupler works very well as an inexpensive system. I think the problem with Hornby couplings is that they magnetise whereas the Bachmanns are non-magnetisable. If you have NEM pockets fitted it is simple to replace the Hornbys with Bachmanns for little cost. Once fitted under the sleepers and the track is ballasted there is no evidence that the magnets are there and certainly will not snag anything passing over. Problem is remembering where they are. This is solved with a small spot of white paint on the adjacent sleeper. If you want to see it in action I have put a video clip on youtube of the uncoupler in action:


This clip is an early one I made of kit made wagons that I had to fit pockets to. You might notice that the guards van coupling to coal wagon is opening when moving forwards under tension. It is crucial that the pockets are fitted at the correct height to NEM specifications otherwise problems arise.

Cheers

Keith
 

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Why don't any manufactures make an uncoupler with a handle as Triang used to? I have tried everything on my railway and ended up using clear plastic strips in sidings; these are fine under tension but I defy anyone to say that their wagons/coaches never uncouple unneccessarily. If you enjoy shunting then it is a problem. I now tend to run full length trains but it is nice to shunt and make up trains now and again.
There is a big market out there for someone.
 

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QUOTE (Oz the Dog @ 11 Aug 2010, 14:22) <{POST_SNAPBACK}>Dave

The Kirby uncoupler works very well as an inexpensive system. I think the problem with Hornby couplings is that they magnetise whereas the Bachmanns are non-magnetisable. If you have NEM pockets fitted it is simple to replace the Hornbys with Bachmanns for little cost. Once fitted under the sleepers and the track is ballasted there is no evidence that the magnets are there and certainly will not snag anything passing over. Problem is remembering where they are. This is solved with a small spot of white paint on the adjacent sleeper. If you want to see it in action I have put a video clip on youtube of the uncoupler in action:


This clip is an early one I made of kit made wagons that I had to fit pockets to. You might notice that the guards van coupling to coal wagon is opening when moving forwards under tension. It is crucial that the pockets are fitted at the correct height to NEM specifications otherwise problems arise.

Cheers

Keith

Keith.
Thanks for the video. Interesting to see this system in operation. In the video at 41sec a set of couplings between two of the wagons failed to rise. Is there a set height for the little wire arms ?
 

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Hello Keith

Very interesting video.

I have to say that I am a Kadee man and have no plans to change but the system you use is extremely interesting, however if I were to use that system I would have to use electromagnets as the noise and distraction of the coupler hooks going up and down as you backed the train over the permanent magnet would drive me to absolutely crazy.

Which only goes to prove "no two modellers are looking for exactly the same thing!"

Thanks for posting the video
 

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QUOTE (paul stapleton @ 11 Aug 2010, 17:27) <{POST_SNAPBACK}>Hello Keith

Very interesting video.

I have to say that I am a Kadee man and have no plans to change but the system you use is extremely interesting, however if I were to use that system I would have to use electromagnets as the noise and distraction of the coupler hooks going up and down as you backed the train over the permanent magnet would drive me to absolutely crazy.

Which only goes to prove "no two modellers are looking for exactly the same thing!"

Thanks for posting the video

Hi Paul.
Do the Kadee's open like that when pushed over the magnets or do you have to stop first ?
 

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Hello 34C

As usual you make very relevant observations...........

I have recently built an Inglenook Sidings layout for my Club to take to local events and encourage local members of the GP to "have a go" ... I learnt a lot about couplings ..............

I used a Bachmann loco and six latest Bachmann wagons and Hornby uncoupling tracks ......... DISASTER!!!! Unwanted uncoupling all over the place! The Bachmann coupling may look like the Hornby one but it is nowhere near as good if you want to use uncoupling ramps as ( as you say ) the under-cut is nowhere near big enough. I use Bachmann couplings close coupled on my "proper" stock and they work fine but I don't use uncoupling ramps.

So now on Inglenook Sidings the Bachmann SALTY diesel ( THOMAS range ) and the Bachmann wagons all have Hornby couplings and everything works very well.
 

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Hello Tony

Kadees just like Tri-ang/ Hornby/ Bachmann etc rely on the couplings being under tension when pulled over magnets ( or ramps in the case of Bachmann/Hornby ).

Personally I always use electromagnets with Kadees but someone in our Club has used hinged magnets which normally hang down but are raised by a piece of string or cotton for uncoupling .

Kadees of course move horizontally rather than vertically to uncouple..............

Regards

Paul
 

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QUOTE (paul stapleton @ 11 Aug 2010, 17:45) <{POST_SNAPBACK}>Hello Tony

Kadees just like Tri-ang/ Hornby/ Bachmann etc rely on the couplings being under tension when pulled over magnets ( or ramps in the case of Bachmann/Hornby ).

Personally I always use electromagnets with Kadees but someone in our Club has used hinged magnets which normally hang down but are raised by a piece of string or cotton for uncoupling .

Kadees of course move horizontally rather than vertically to uncouple..............

Regards

Paul

Thanks Paul.Is it the Kadee electro magnet you use ?
 

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I have managed good results with clear plastic embedded over a few sleepers in the track. A few trial and error attempts at shaping it may be necessary to get it to work well. It is possible to get it working while remaining narrow and low enough to not foul vehicles/locos.

It is impossible to get reliable results if the ramp is anywhere near a curve - both wagons should be in a straight line as their uncouplers are over the ramp.

Tip 1: When hauling a rake of wagons without the desire to uncouple any wagon, keep the train running at a steady speed without snatching, so as to maintain the tension between couplings. This is easier with a feedback controller or feedback decoder. And this is another reason to keep some distance from curves.

Tip 2: Keep the track as flat as possible. Local dips and bumps cause wagons to bunch together, losing the lock in the tension lock and resulting in undesired uncoupling. In fact, I sometimes bend the track slightly so that the ramp is at the apex of a slightly convex "hill" - this encourages wagons to remain in tension while crossing the ramp. Conversely, if by chance you have a concave dip at the ramp's location, random uncoupling is more likely.

Using this method and a good quality back-EMF decoder, under computer control, I can repeatedly get a train to draw to a stop with the loco coupler right over the ramp, reverse the loco two millimetres to release the tension - the ramp then disengages the couplers, and then the loco draws away. When hauling a train over the coupler at a steady pace, there are no random disconnections.

Hope this helps
Mike
 

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[quote name='woolwinder' date='11 Aug 2010, 19:29' post='151150']
Patrick,

Fleischmann have a manually operated uncoupler ramp (with a lever).

Thanks for that, I will get a few and put them in for when I relay my track, it is all being moved in the next year or so. I may even try some of the other Fleischmann stuff which looks very handy.
 

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Patrick,

What make and type of track have you ? I have a mixture of Peco and Fleischmann, both Code 100. The Fleischmann uncoupler is built in to a short piece of track, complete with ballast base, but it is easy to join to Peco 100.

gresley
 

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Discussion Starter · #18 ·
Hi all,firstly many thanks to those who have contributed to this thread for taking the time to discuss this subject yet again lol I understand what people are saying about having to keep the train in tension whilst crossing the plastic uncouplers (be they proprietary or homemade) as that's the exact problem. The only uncoupler I have on a running line is just before a curve (can't be helped) and is there to uncouple the loco at the station and then run it 10cms forward before reversing it back up a point into the shed to be replaced by another loco. this photo may helpexplain

The uncoupler is located to the left of the platform just before the point, the curve starts at the left hand edge of the photo. What happens is that a loco hits there and then slows down or judders as it passes the point and bingo, uncouple time. I've fitted a bit of plastic there now and run a couple of trains over it, it doesn't snag as much as the proprietary system and so far no false uncouples which is good news, but sometimes it won't uncouple at all arrrgh!! lol.
Thankyou for the video on the magnetic uncouplers, most enlightening though I guess that would mean changing all my rolling stock to bachmanns, which is possible for some but not all since some older stock has the "volvo buffer beams" (love that description btw). Do you find that the small activator wires catch on anything with being so low down? Thanks for the input about the elctromagnets, would love to source them but due to lack of space under the boards and the need to be portable I wouldn't be able to run the wiring required: looks really good to see it in operation though

Point noted about fitting on curves, tbh it isn't necessary with the thin plastic method as I can place a small strip at the exit of the curve much closer than the proprietary systems.
The point about wear and tear on the plastic strip is valid, and something I was wondering about myself, along with potential damage to the underside of stock. I shall have to keep an eye on that if I go down that route I guess.
Right I'm going to go downstairs and have a fiddle with the plastic strip, see how I get on. thanks again all

Dave
 

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Try and find a way to install the uncoupler away from curves/points. This really is your best bet. You're being too ambitious by placing the uncoupler so near the point.

Why is your loco juddering at the point? Try to find out why the juddering happens. Do all your locos exhibit the same problem? Some common reasons include:
- momentary short-circuits as a wheelset bridges the frog
- poor electrical conductivity due to gaps at the frog
- mechanical stiction traversing the point, perhaps due to a rigid frame or incorrect wheel back-to-back spacing

If the problem is due to momentary short-circuits, you may be able to improve matters by isolating the inner diverging point rails from the adjoing tracks, or by modifying the point by isolating part of the frog tip in some manner.

If the problem is due to gaps at the frog, you may be able to improve matters by modifying the point in some manner or by improving the pickups on the loco.

If the problem is stiction, you may be able to improve matters by altering wheel back-to-backs or possibly spiltting some axles. A good controller or decoder with back-EMF may also help against stiction by compensating for sticky areas.

It may be that using a different loco solves the problem.

It may be that using a different point solves the problem if it's due to a short-circuit or gap. Fleischmann (profi) turnouts are good performers here, particularly the express point which has a swing-nose rather than a frog and eliminates frog problems - although it is rather long. The short Fleischmann turnouts are also good. You may also need to replace the compensating curve with a Fleischmann one, if you want to achieve parallel tracks. The overall geometry will only be slightly altered.

Another idea: approach the uncoupler very slowly indeed - if this is not precluded by whatever is causing the juddering - slow travel is aided by a good controller with back-EMF. This slow approach may be enough to reduce the tendency of wagons to bunch together.

Perhaps you could create a slight "well" just before the uncoupler so that the train "runs back" due to gravity, after the judder, reinstating the tension.

Hope this helps,
Mike
 
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