Kadee coupling

[Blind Bruce]

I noticed that my Kadee equiped cars and locos will not couple on my 22" radius curves.

Does this mean that they require a straight section of track to uncouple as well?

[Don Gibson]

No. but curves do hamper thing a bit.

I believe KDs are designed to couple on 22" radius (but don't quote me).

Sam Cook @ Kadee is their 'Applications Specialist '.  Maybe  the car's length vs. radius comes into play.

Dumb Don

[jecorbett]

Make sure your couplers swing freely so that they center themselves prior to coupling. Sometimes if the cover on the coupler pocket is too tight, the coupler won't center, preventing it from coupling. Even with couplers centered properly, coupling on a 22" curve is going to be difficult.

[cwclark]

I use Kadee couplers and they have a hard time coupling on my 30 - 36" radius curves. Your best bet is to couple on straight track or use a wooden chop stick or skewer to push  over and hold the coupler in line to the car's coupler you are going to couple to while backing the train.

[engineerjoey]

Let me add that there may be a "Handedness" to this problem. 

It's seems that my couplers work sporatically on track that curves away from the lead car's coil spring... but they actually work better going the other way. They seem to be trustworthy on certain S curves too. 

Anyone notice that? 

[loathar]

I've got 24" and bigger and they don't work most of the time for me either. That is one of the things that truck mounted horn hooks were good for. You could couple on a 15" with those ugly things.

[jeffrey-wimberly]

I use 18" radius curves and most of my kadee's work perfectly. Some, however, like to be hard cases.

[el-capitan]

My main yard was designed with 84" radius curves (I have oscale, 84" would be 42" in HO) and coupling is a crap shoot. Most 40' cars and shorter will work most of the time. The longer the car the less likely they will couple. Fortunately the yard throat is all straights and that is where most of the coupling takes place so the curves are not a huge issue. I try to design straight sections into my layout wherever coupling takes place.

Also, it's been a while since I used a magnet to uncouple cars but I believe the same rules apply so keep the uncoupling magnets on straights.

[el-capitan]

I use 18" radius curves and most of my kadee's work perfectly. Some, however, like to be hard cases.

Are you saying you can couple cars together on an 18" radius? Without human interference? Are the couplers mounted to the carbody or the truck?

[fwright]

My main yard was designed with 84" radius curves (I have oscale, 84" would be 42" in HO) and coupling is a crap shoot. Most 40' cars and shorter will work most of the time. The longer the car the less likely they will couple. Fortunately the yard throat is all straights and that is where most of the coupling takes place so the curves are not a huge issue. I try to design straight sections into my layout wherever coupling takes place.

Also, it's been a while since I used a magnet to uncouple cars but I believe the same rules apply so keep the uncoupling magnets on straights.

The LDSIG Rule of Thumb for curve radius (http://ldsig.org/wiki/index.php/Curve_radius_rule-of-thumb) says it takes a radius 5 times as long as the car for automatic coupling to work with minimal manual fiddling.  In HO, that translates to a 30" minimum radius for a 40ft car to couple automatically.  This assumes body mounted couplers.

yours in coupling

Fred W

[loathar]

I use 18" radius curves and most of my kadee's work perfectly. Some, however, like to be hard cases.

Are you saying you can couple cars together on an 18" radius? Without human interference? Are the couplers mounted to the carbody or the truck?

I was wondering that myself when I saw it. Hey Jeffrey-Where do we get some of those magic KD's at? Mine aren't even close on 24".

[jeffrey-wimberly]

I use 18" radius curves and most of my kadee's work perfectly. Some, however, like to be hard cases.

Are you saying you can couple cars together on an 18" radius? Without human interference? Are the couplers mounted to the carbody or the truck?

I was wondering that myself when I saw it. Hey Jeffrey-Where do we get some of those magic KD's at? Mine aren't even close on 24".

They're mounted on the car bodies. I use all #5's whenever possible. The ones that give me problems are Kadee's also but are different #'s. They're getting changed to #5's ASAP. The main part of having them couple successfully over and over is that they must be able to move absolutely freely. Any resistance at all, no matter how slight, will take them off center and two couplers on different centerlines will not couple. They must be able to center themselves instantly. BTW, I don't use graphite. It almost always finds it's way down to the rails and create tons of traction problems.

[loathar]

Jeffrey-Do you use any lube at all?

[jeffrey-wimberly]

For couplers I use Dexron/Mercon transmission oil. It's thin and plastic compatible. For gears and bearings I use a lube for R/C vehicles called "Trinity". You asked.

[SROC99]

  I've been watching this thread develop for a while before I commented. Thanks to you all that have commented.

  Kadee couplers were never designed to couple on curves. However, in certain circumstances they will couple on curves. This really depends on the length of the particular cars (locos) and how much overhang there is from the pivoting point of the trucks to the end of the car and the end of the coupler. The tighter radius and the longer the car and over hang the less likely the chance of coupling on a curve. Uncoupling is mostly impossible on a curve without manual help.

  Although it's the modelers' prerogative of what lubricant they choose, Kadee Quality Products does not recommend using any liquid or petroleum base lubricants. Couplers may work nice for a while but soon you'll fine they become dirt and grime magnets. We only recommend dry graphite to be used in our couplers, there are some Teflon® based dry lubricants that work OK but graphite seems to stay much longer.

 

Sam Clarke

Kadee Quality Products

[tomikawaTT]

Sam,

Thanks for the manufacturer's viewpoint on this question, which has (in this instance) generated rather more light than heat.  I, too, have been lurking, to see if I can learn something.

I've had good luck coupling 100mm (over pulling faces) cars on 610mm radius and larger curves - but less than wonderful results with longer cars.  The key seems to be getting the couplers to line up almost perfectly (except for meeting angle.)  If one coupler is to the side of the other, it's time to reach for the lateral adjustment tool (which, in my case, is a chopstick.)  Scale is HOj, most couplers are either #5 or #6.

Chuck (modeling Central Japan in September, 1964)

[NSlover92]

Plain and simple, here is what I think works, dont count of them to couple on corners, stand there and watch with a screwdriver or the plastic uncoupling tool or chop stick and if it doesnt look like it will line up just take the extra effort to hold the coupler over, I know its alot to do you might acidently burn 2 calories.

[Don Gibson]

THIS raises a good question:

Do prototype RR cars couple on curves without manual assistance? BRAKIE?

[NeO6874]

I would assume so, granted you would need a *very* gentle curve and cars that are short enough to have the coupler centers relatively close.