Kadee vs. traditional?

I have found the the Kadee #805 couplers, the one I use, couple pretty well with MOST manufacturers "lobster claws". I have found some exceptions on some guests locomotives, and then we have to use a transition car.

Personally, no.  I've converted all mine to Kadees and over the years I tried to keep a few with the large couplers, but they just don't work together 100% of the time.  if your layout was perfectly flat the combination may work, but may layout is not perfectly flat.

There's nothing wrong with making a train using just Kadees, while keeping the rest using the traditional coupler.  Once you do convert you might see what all us 3RS guys have been talking about

Jack mentioned a "transition car" and I want to be sure everyone who reads this knows what we're talking about.

A Transition Car is one that has a Kadee coupler on one end and a Lobster Claw coupler on the other.

So is most of the compatibility problem vertical alignment, or do they just not close around some of the toy train couplers?

Also- How do you guess-timate the curve that couplers can take?  Going from truck mounted to body mounted (i.e. the front of a steam engine) has to seriously change the functional curve radius.  Or do you actually have to mount them such they can still swivel from a point closer to the axles?

As long as you use a Kadee gauge to set the height of the Kade, it will pretty much be in the center of the lobster claw coupler. Minor track variation should not cause it to uncouple. The problem with some lobster claw couplers (I find mostly with MTH) is the roundness of the opening part of the coupler is too smooth or round. This caused the Kadee movable claw to slip out. Lionel, Atlas, Weaver seem to have a little burr or sharpness on the inside of the claw that holds the Kadee better. All my engines have the lobster claw ( only one MTH engine ) couplers yet all my freight have Kadee and I have no problems (except with the MTH).

Curves are the one area I think a lot of people will have trouble with.

I would say for cars 50' and longer, nothing short of 072, for cars 40' and shorter, 054.

I have 054 (sidings) and 072 (mainline) curves on my around the wall 12x12 layout and mostly 40' rolling stock, I do have a few 50' cars and 84' passenger cars.  All work well around 072, but certain combinations of 50' cars and engines (say a GP9) are close, just don't have any "S" curves in your trackwork.

Around the wall layouts will allow much wider curves, I wish I had realized that when I built mine, I could have gone 090 with no problem on the mainline.

I currently running a mix. What I have found that I have issues with Weaver lobster claws and kadees.(the claw being a just bit too thick) K line come undone to easily. Best matches seem to be Atlas and MTH. The best thing I like is I am able to by 2R cars that come with kadees. the only issue I have found is scale wheels do not work well with fast track turn outs(Derailments in reverse) and 060 curves are the smallest you can use with 50 ft box cars. You will find that once you start converting to Kadees you will not go back to the lobster claws.

Rule of thumb with "S" curves:  Whenever possible, include a straight section in the S curve that is at least equal to or greater than the longest car you have in your roster.  This will greatly lessen the chances of exceeding the lateral motion limits of the coupler swing, thus lessening the chances of derailments.

As to Kadees mixing with 3 rail couplers, most of my rolling stock is Kadee with the rest in queue for a Kadee conversion.  But mating Kadees to the 3-Rail lobster claw couplers is certainly doable.  My experiences are similar to what others have stated; in my case Lionel and K-Line 3-rail couplers are the worst offenders when it comes to the Kadees staying coupled.  The tightness of your curves combined with the length of the cars are the greatest factor of how well the two types of couplers will work together since Kadees, being fixed to the underframe will have considerably less available coupler swing around curves than the traditional truck-mounted couplers.  If you have no intention of converting everything to Kadees then having transition cars with Kadees mounted on one end and the 3-rail coupler on the other is the best bet as was previously mentioned by others.

One other thing. If you have Atlas scale rolling stock you can purchase the atls adjust a coupler which is the scale/kadee type coupler. They come in 2 variants 50t,70T. But to be honest they both look the same to me. They mount to the truck assembly not to the car body like Kadees. 

the 805's yes....the new 740 series not so much.

The other thing I recently discovered, the 805's work fine with the claw UNLESS you're running on a grade. The slack created on the down hill side of the grade causes them to uncouple every single time. Flat surfce running...no problem.

I'm pretty sure that Atlas stopped offering that "adjust-a-coupler" item, especial since those "scale" couplers kept breaking. I eventually had to throw every single Atlas "scale" coupler in the trash, as they all broke.

The current "re-designed_ Atlas O "scale" coupler no longer come in that previous "adjust-a-coupler format anyway.

The current "re-designed_ Atlas O "scale" coupler no longer come in that previous "adjust-a-coupler format anyway.

That's really a shame, the truck-mounted part was a good idea, especially for those who have tighter radius curves.  I think I have maybe 1/2 dozen of them left, not in use as of now.

Hot Water, if you replace the broken old Atlas coupler with one of their new couplers will it work in the Adjust a Coupler format? I don't have any Adjust a Couplers but I did replace a bunch of older Atlas couplers with their new coupler as preventative measure.

Yes, they should. As I remember the "new redesigned" Atlas O scale coupler uses the same gear box as the old one. But since I have standardized on all Kadee brand couplers, I haven't paid an attention to what Atlas has done.

quote:

Rule of thumb with "S" curves:  Whenever possible, include a straight section in the S curve that is at least equal to or greater than the longest car you have in your roster.  This will greatly lessen the chances of exceeding the lateral motion limits of the coupler swing, thus lessening the chances of derailments.

My layouts have never approached the size and complexity of some of the folks participating on this board. I have always used traditional "O" or "027" gauge track with original Postwar switches. I find that even a short piece of straight track helps. (But John's suggestion is probably a better practice)

S curves have a much greater impact on cars with body-mounted Kadee couplers than with the truck-mounted 3-rail knuckle couplers.

Truck mounting keeps the couplers fairly well-centered over the middle rail. However, on an S curve, the car ends will be moving in opposite directions as the rails curve first one way then the other. On all but the widest curves this lateral motion will cause a derailment with body-mounted couplers.

Also, since the gap between cars is less with Kadees, on tight curves corners will touch on adjacent cars. This will be more pronounced obviously in reverse as cars are pushed together. For example, I've managed to pull 50' cars through O42 curves, but corners will touch in reverse on those same curves.

Jim

Is there any advantage to mounting kadee couplers on a toy train type truck?  This would retain some of the tight radius capability while improving the look without going all out on mounting couplers to the carbody.  Has anyone considered this or is it usually one way or the other?

Also I like the idea of having a straight track the length of your longest car in and s-bend, I don't necessarily think its practical in alot of situations, but I like the idea for sure.

Several members have truck mounted kadee's on this on this forum, engines and cars. The advantage is they still run through those super tight curves.

Having that piece of straight track is NOT ALWAYS possible.

I have body mounted Kadee's, but I haven't truck mounted any of them yet. All of our curves are a minimum 072, and still some of the boxes and coupler shanks are modified to allow more swing, especially on the 21" passenger cars.

Truck mounting Kadees is possible, but involves a lot more work. Many of today's brands of rolling stock (except Lionel) have coupler mounting pads (some pre-drilled) for body mounted Kadees. They usually just need some shimming. Truck mounting would be more difficult.

Jim