Atlas O 2-rail conversion to 3-rail

Matt's tip is spot on but I want to add something.

I would say that over 90% of 2 railers dislike the first Atlas coupler. I personally despise them and #1) I don't allow them on my railroad, and #2) would never, ever buy them at a train show or trade for them. If I were you and the car has the original Atlas coupler I would just throw them out. However, if it is a newer Atlas car that has the 2nd generation coupler then by all means follow Matt's advice and I'm sure that you will be able to sell them or trade them away.

If you need to be able to tell which coupler is which the older version has no spring on the side of the knuckle. The 2nd gen coupler has the spring just like a KD coupler.

I just bought an Atlas 3 rail car last night with the plan of converting it to 2 rail. Email if you are interested in the trucks. They are brand new and have never been out of the package.

There are at least 4 generations of Atlas "scale" couplers all using a coupler pocket with hidden mounting screws spaced different than that used by Kaydee.

Version 1: 1970's made in Austria by Roco for Atlas with a head and knuckle based on the CLW magnetic coupler of the 1960’s.  The pocket, shank/head, and knuckle were molded with an industrial plastic.  They are very strong and I’ve never seen one break.  In extreme service John Armstrong regularly ran a 40+ pound ore train up 3% grades with these couplers. The knuckle has no external spring and used an internal sloping shelf and gravity to close the knuckle. Its primary operational weakness was false uncoupling generally due to friction between the metal glad hand/air hose and the coupler head.   My fix is to drill out the upper and lower holes (2 different diameters) slightly larger to allow the glad hand to swivel very freely in the coupler head. While the Atlas/CLW coupler had a more prototypical appearance than a Kaydee, operators generally preffered Kaydees for their broader gathering range on curves and delayed coupling feature.  John called Kaydees "promiscuous" -they would couple with almost anything ranging from scale dummies to Lionel lobster claws.

Version 2: 1990's AtlasO made in China. This coupler retained the same design as version 1 but both the knuckle and head were cast metal. It was a failure from 2 perspectives. The knuckles broke free of the body under load due to poor quality pot metal - and those that didn't break tended to stick open due to the cast metal not being as "slippery" as the industrial plastic. My fix for these cars was to remove the "new coupler" and mount  Atlas/Roco couplers in the AtlasO box.

Version 3: 2000's  AtlasO addressed the false closure issue by redesigning the metal coupler to use a thin wire closure spring. It addressed the false opening issue, but  the broken knuckle failure rate remained high.

Version 4: 2011  Responding to continuing customer complaints, AtlasO again re-designed the coupler head - this time to mirror a Kadee with the external coil closure spring.  Unfortunately they retained the AtlasO coupler shank and 40 year old design pocket. The latest coupler has been commented on by several as not coupling as well as a Kaydee due to the centering and knuckle springs being too stiff.  Several have addressed the issue by replacing the springs with spares from Kaydee.

All 4 versions of Atlas couplers are a pain to work with as removing the pocket lid to repair/replace the coupler requires a fair amount of judiciously applied force. Perhaps version 5 will have better springing and a coupler pocket designed with an external lid retaining screw.

We all would be a lot happier if Atlas just went with Kaydee couplers in the first place.

Ed Rappe

ED thanks for the in depth history on the Atlas scale coupler. I've never seen or even heard of what you call version #1. All my '70s Atlas stuff has these really large couplers on them. Not anything near what I would call scale. I got the impression that the original poster was talking about Atlas cars from the late '90s to present.

I didn't know about version #3 either. I guess because I replaced any Atlas couplers with Kadees. Well, learn something new every day.

I sorry to hear that the newer couplers aren't well received. I've used them sparingly when I had a layout and didn't have any problems. I hope I don't encounter those problems when I get the layout back up. I guess I could always go to a softer spring like you said.

All 4 versions of Atlas couplers are a pain to work with as removing the pocket lid to repair/replace the coupler requires a fair amount of judiciously applied force. Perhaps version 5 will have better springing and a coupler pocket designed with an external lid retaining screw.

 

We all would be a lot happier if Atlas just went with Kaydee couplers in the first place.

Well, I totally agree with that.