Kaydee Coupler Installation on IHC Passenger Cars

[BradKT]

Can anyone tell me about how to install Kaydee #508 couplers on International Hobby Corporation (IHC) streamlined passenger cars?  I checked the Kaydee site and they indicated that the #508 coupler (the same one for Rivarossi) was the right one to use.

Before I buy a bunch of #508 couplers or mess anything up, I took a good look at the IHC passenger trucks and what gave me pause was that the IHC trucks have "horn hook" couplers extending out on a shaft from the truck assembly as one part with the horn hook on the end.   The truck and shaft are made of plastic.  Are the horn hook couplers supposed to be cut off? 

Does anyone know of a set of instructions re: what to do to install Kaydee #508 couplers on these type of passenger cars that I can use as a reference?

[Yampa Bob]

On all my older cars, I cut off the horn hook piece and mounted the couplers to the bottom of the body. 

I don't have any long passenger cars, so I don't know which coupler would be correct, I guess Kadee knows best.  I only use Kadee #148 as they are easy to install.

Bob

[cmgn9712]

508 Kadees replace the long x2f with a plastic bar  with the Kadee out at the end so they are still truck mounted (required for typical curves). Body mounting requires curves in the 25-30 inch range. The 508 are screwed to the IHC frames after some changes by cutting away a small amount. Kadee will probably send you a copy of the instructions, or just buy a set to see them.

[SteamGene]

I have both 72' streamlined and 85' heavyweight IHC cars.  In all cases I have bodymounted with #5s and no trouble at all.
Gene

[WoundedBear]

Here are the instructions for mounting the 508 to IHC passenger cars.

http://www.kadee.com/conv/pdf/i141.pdf

Sid

[Yampa Bob]

I run on 18" radius curves with all body mounted couplers.

I never understood the theory that long truck mounted couplers are required for long cars, or any other car for that matter.

A body mounted coupler pulls a following car to the outside of the curve.  The pulling force is tangential to the curve.

This outward instead of inward pulling is due to the end overhang of the leading car as it goes around the curve.  As the overhang swings out so does the coupler.  If the end overhang was excessive in relation to the pivot at the bolster, only then are larger curves required.

The other fallacy is that you can't pull 30 or 40 cars around an 18" radius.  Again, with body mounted couplers, the leading car pulls the following car toward the outside of the curve, in effect overcoming the old rule "the shortest distance between two points is a straight line".

I keep all my cars close coupled as possible.  The only thing that looks worse than long cars on tight curves is a huge gap between the cars.  Railroads that haul intermodal discovered that the closer the cars are coupled, the less fuel consumption due to decreased wind drag and turbulance between the cars. 

If you don't believe this outward pulling effect, put two cars on a curve and watch the coupler action.  The lead car coupler may be swung to the inside due to the outward swing of the overhang, but the following coupler is almost straight.  It doesn't matter how many cars are hooked up, each one will pull the next one to the outside.

http://en.wikipedia.org/wiki/Tehachapi_Loop

Bob

[Woody Elmore]

Bob -- This is just a guess but maybe the older x2f couplers didn't work the way knuckle couplers do. If the x2f was mounted properly it was offset to the left. The physics might be different.

As for derailments, I'm sure manufacturers designed their HO cars for 18" radius. A lot of derailments can be attributed to other factors - out of gauge wheels, poorly laid track and excessive speed come to mind.

[Yampa Bob]

The only thing I know about truck mounted couplers is they get replaced with body mount Kadees before the car is put into service. 

A future project will be to research the relationship (distance) beween the bolster pivot and the coupler knuckle on real cars.  It seems to vary depending on era, car type, weight distribution and balance, and probably geometric limits as well. 

The quirk of an engineer is having to know how and why everything works. 

Bob

[grumpy]

After running both hook and horn and knuckle couplers it is my firm opinionthat the only advantage to the knuckle coupler is appearance and attempt to model as close to reality as possible.
Don

[SteamGene]

Grumpy - have you ever tried to push a long cut of cars backwards with horn hooks?
Gene

[grumpy]

If I pushed a long train period on my layout it would be like the tail chasing the dog.
Don

[SteamGene]

That's the advantage of the knuckle couplers - pushing a long cut or train backwards.  If you don't need to do that, horn hooks work fine.
Gene

[Woody Elmore]

Back when there were loop type couplers, dummies and the Baker hook, coupling and uncoupling was a problem. Did you ever see an old Mantua uncoupling ramp?

Kadee came along with the "K" series coupler that used a little diamond ramp. They were generations ahead of anything else. They were reliable and looked a lot better than the Mantua loop.

At about the same time, the NMRA formed a coupler committee and that committee came up with the X2f design. It was never well accepted. Part of the problem is that the design was made available to all manufacturers and got to be called the "NMRA" coupler. The issue was that different manufacturers couplers often weren't very compatible. These "NMRA" couplers kept a train together but were hard to uncouple.

Kadee then improved the "K" series buy using magnetic ramps; the new series were labelled "MK". They worked well and were a quality product. Properly installed, they last for ages with only a little maintenance.

As for backing a string of cars, That was done in our club yards all the time. We required body mounted Kadee couplers on all cars and had a car inspector who checked to see that they were proper height, etc. If a cut of cars going backwards derailed it was usually due to a ham-fisted operator.

I can't tell you how many pairs of x2f couplers I discarded over the years. I couldn't imagine using anything else but a Kadee coupler.

[grumpy]

Why the preference for Kdee  over McHenry's. I have found the McHenrys easier to install in a lot of cases than Kdee's. I oersonaly do not have a preference but use the best one suited to the application.
Don

[Guilford Guy]

McHenry's are plastic, and are more prone to break in a longer train. Kadee's are metal. The newer whisker couplers do not have the copper plate, so they are a bit easier to install.