Atlas RS-3 is a free Model Railroad Discussion Forum and photo gallery. We cover all scales and sizes of model railroads. Whether you're a master model railroader or just getting started, you'll find something of interest here.


Hi there,

I purchased an Atlas RS-3 engine, at a good price, and when I went to try it on my layout, on the turns it was derailing the first car that was attached to it, then I noticed that on some tight turns, the coupler couldn't turn enough and was pulling the car's coupler out of the rails, so derailing the first bogie.

Is this something that can be solved or is it a big problem for this engine to operate on tight turns?

I will try to post a photo of what I mean.



OK here it comes

Top View


Side View


When I looked at it over and over again, it seems that on the engine coupler there is no more room where to turn, so the coupler gets stuck in the furthest position and since there will be no more room where to turn, it pushes the car's boogie out and derails it.

Can this problem be solved somehow? I cannot fix the layout's turns cause there is more then one turn that this thing happens at, besides if I buy similar engines the problem will not be with one engine :S

Kindly help....



New Member
not sure how sharp the radius is for your turns. the coupler that is on the locomotive looks like the nmra horn-hook type. due to the way that coupler works it pushes to the side and when the locomotive turns to the left it will push the car following it to the outside of the curve. if you change it to a kadee type then there will be less of push and may solve your problem.


I'll take a look around and see where I can get this 20 pack KADEE #5s and #58s , mostly not from where, but if the seller can ship them to me :S

Affiliate Disclosure: We may receive a commision from some of the links and ads shown on this website (Learn More Here) is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to - An online railroad bookstore featuring a curated selection of new and used railroad books. Railroad pictorials, railroad history, steam locomotives, passenger trains, modern railroading. Hundreds of titles available, most at discount prices! We also have a video and children's book section. - An online model railroad bookstore featuring a curated selection of new and used books. Layout design, track plans, scenery and structure building, wiring, DCC, Tinplate, Toy Trains, Price Guides and more.