I have a question about Kadee decouplers. Has anyone had them work reliably? In other words, let you uncouple a car and allow the car to be pushed back without recoupling in a reliable manner. I have replaced almost all of my rolling stock original couplers with kadee and still can’t get the correct operation. I am using #321 magnets.sometimes they won’t uncouple and if they do the coupler won’t open far enough to keep from recoupling when you push the car back. I also used graphfite lub in the boxes.
I’m assuming that you’ve read the instructions and know about backing the cars over the uncoupler and pulling them slightly apart before trying to back them together in the delayed position.
I have the 321, as well as the 307 and 308 uncouplers. There are a couple things that will make them not work properly.
First, the #321 has to stick up very slightly above the rail head, Kadee sells a gluing jig that centers and holds the magnet at the right height while the glue dries. They also work best if mounted in a straight section of track.
If the uncoupler is installed properly, the coupler installation may be at fault. The coupler not only needs to open over the uncoupler, it also needs to pull off center in the coupler box, as shown in the second picture below.
If the coupler is too tight in the box, no amount of powdered graphite will make it move with the magnet. Take the cars, not coupled together and move them over the magnet by hand. As the coupler is moved over the magnet, it should not only open, but pull to the side, as shown in the animation on the link.
I have three under-track magnetic uncoupler magnets, one from Kadee, the other two from Bachmann. All three work very well. I’ve had no problems with them.
There are lots of variables here that could affect the so-called “delayed uncoupling” feature. What first comes to mind is the amount of friction between the drawbar and the coupler box. Even using graphite for lubrication, if there is too much friction, the couplers will not swing far enough to the side. The instructions call for burnishing the drawbar before installing. I have found this helps but does not always cure the problem.
If you are using #5’s or any coupler that employs the copper spring insert, sometimes these can become bent during istallation or the tiny strip on the one side that provides the spring action can move out of the springing position.
On a few cars, the coupler box may be too narrow to allow full side-to-side movement.
Finally, how you center the magnet between the rails can be critical. Measure carefully when installing so that it is dead on center.
I’m not using the KD magnets. I have some other cylinder magnets I’ve been trying with good luck. One problem I’ve found with the new whisker couplers is the centering spring seems to be weaker than than the bronze #5 type spring. The magnets want to pull the whole coupler all the way to the side instead of just opening the knuckle. Then they don’t line up right when you go to push the cars back.
You’re describing the delayed uncoupling, which requires the coupler to be pulled off center. Kadee makes an uncoupling magnet that does not use the delayed feature, #312. If they’re not returning to center, look for binding in the coupler box.
All of the well-executed layouts I’ve had the opportunity to operate on disdained magnetics for uncoupling. All uncoupling was done manually by stick. Your experience might help to explain why.
The main reason many operators don’t like magnets is because of unwanted uncoulings at inopportune times. There is one railroad I operate on where this problem is most annoying. Park a train in the hole and as you leave half the train is still in the siding. Magnet placement has to be carefully planned to avoid this sort of thing. I use skewers on my railroad.
We use uncoupling magnets on our HO club layout and they work fine. Of course all rolling stock has to pass a check in and the magnets are not mounted in tight curves. Trip pins being too high can be a problem with uncoupling, but the biggest issue is with the draft gear box and centering spring. With your car sitting on a flat surface, push the coupler all the way to one side and then let it return to center slowly against your finger (both directions). Don’t take your finger away and let it spring back quickly or don’t push it back to center. If it doesn’t return to center on its own or sticks to one or both sides you need to check the box, spring, shank and draft gear post for burrs, flash and foreign matter. Check the coupler centering spring and see that it doesn’t move side to side in the box with the coupler. Make sure the spring isn’t bent causing it to ride down on the coupler. You may have to bend the centering spring giving it more or less tension. Check that the knuckle opens over the magnet. If the knuckle isn’t moved by the magnet you either have; improperly installed the magnet, maladjusted trip pin or a bound up knuckle pivot (usually caused by excessive coupling speed or quick trips to the floor). I used to think that most of what I mentioned was a bit excessive but if you want to have reliable hands free coupling/uncoupling it is highly recommended. We also employ uncoupling sticks to aid in coupling and uncoupling where magnets can’t and shouldn’t be placed (mainlines, main sidings and tight curves).
I have a number of these on my layout, and they generally work pretty well. I’ve also got one of the electro-magnet variety, which is on my main line. With that unit, I only get uncoupling when I push the button.
The minimum straight-track requirement is a straight space on either side of the magnet which is at least as long as the longest car/locomotive you intend to uncouple there. If the two cars aren’t lined up when they cross the magnet, uncoupling (and also delayed uncoupling) will not work properly. If you have very long cars, such as passenger cars, with truck mounted (Talgo) couplers, you can relax this requirement for those, because the trucks will keep the couplers centered even if the car is at an angle.
The magnets have to be at the right height, but I’ve found they work fine if they are at exactly the same height as the railheads. I had to do this because some engines, notably my Proto S1 switcher, rides low and “runs aground” if the magnet is set according to the Kadee spec. I found that I had to grind down the ties to seat the magnets so that this switcher would go over them successfully.
Most important, the couplers need to be set up correctly. Others have already mentioned that they must swing freely in both directions, and return to center on their own. The overall height of both the coupler body and the trip pin are also important. GET THE KADEE COUPLER GAUGE! This will help you get your couplers right the first time, when you install them, and with luck you’ll never have to touch them again. I have the trip-pin pliers, too, but if you’re on a tight budget you can make due with needle-nose pliers and a bit of care. I’ve found that a lot of the trip pins need adjustment after the coupler is installed.
Some of us have found “generic” magnets that work as well as the Kadees. You might want to search earlier threads for information on these.
That is the one I was looking for. The coupler trip pin should be just slightly above the magnet and the end should be pointing down toward the magnet. I’ve seen some people adjust them up to the point they curved back up right at the end.
I’ve seen extra long ties sticking out from the track to indicate the position of a uncoupling magnets.
As several others have said, many are taking out magnets for this reason and others. On most of the layouts that I currently operate on the owners have gone to bambo. I’m giving the final two “magnet people” about a year before they decide to take them out as well.
If you properly install, adjust and maintain your couplers, there should be no reason to use skewers or any other device to uncouple them. That said, I realize some locations are better suited to using skewers, etc. and if you can save the expense and time involved in installing magnets, so much the better. But to do away with them entirely makes no sense.
You can remove the magnets provided you have reachable access to all places where you want to uncouple.
Reasons for not using manual uncoupling include: an eye-level height layout, delicate foreground scenery and/or structures, uncoupling spots that are more than 18" from the aisle, main in front of the uncoupling area that sees traffic while you are trying to uncouple behind it, higher foreground track and scenery than where you are trying to uncouple (common in twice-around layouts), etc.
But as has been well pointed out in this thread, making delayed magnetic uncoupling work consistently is not trivial. Locomotives must be very smooth running at realistic switching speeds, track and wheels must clean enough for solid electrical pickup, cars must roll consistently well (but not too well), and cars must weigh enough to automatically couple without “pushing”. All of the above is needed to prevent car separation during pushing or recoupling after unwanted separation.
In addition, just to initiate delayed uncoupling, coupler and uncoupler installations must be spot-on, as the other posters have said.
Given requirements for solid performance in all these areas, I don’t doubt the easy way out is to switch to skewers for uncoupling where layout design permits. These are all also very good reasons for determining your uncoupling/coupling preferences prior to designing your layout, and letting your preferences influence the design.
There are certain areas of model railroading where “attention to detail” is essential. This is one of them. All of the advice on adjustment, alignment, and freedom of movement is excellent.
And for those of you that have N scale, the MT couplers can be made to work as advertised also. I know, because I have done it. However, my choice of magnet for N scale is the 308 under the track one, and I cut it in half. (Because N is half HO.)