I just received 8 different ROCO wagons today in the mail. As you can imagine I was very happy and ready to start running them around my layout. Unfortunately to my dismay I started having derailment problems almost immediately on my switches and in R1 turns. This was a new experience for me, I haven't had something like this happen since I started running trains on my new layout about six months ago, which consists of all new c-track, all Marklin cars and engines.

After being a bit discouraged I started wondering if wheel sets needed to be changed so I started comparing flange depth, and the gauge of the wheels. And nothing really stood out, I had enough play when the wheels where on the c track that changing the gauge a bit in or out wouldn't have an impact. Then I looked closer and noticed that the frogs in the switches were off just a bit with the rails leading to the frogs that when the wheels would roll past that point they would hit the rail and roll up and out of the track. This was true also for the the tighter radius curves, the end of the rail was just slightly out of alignment and so when the cars would role through a tight turn it would hit the rail and bounce out of the c track (we are talking very slightly, such a small difference I had to run a finger nail over some of the rails to really feel the difference.

So I went around the entire layout looking at my rail alignment in the curves and looking at the frog and rail alignment in the switches and made sure everything was perfectly lined up. Once that was done, the problem was solved and everything has been running great.

I am wondering if others have had this same experience and why is it that Marklin cars and engines had no problem with the c track with the slight alignment issues and the ROCO cars did. It isn't a quality issue with the ROCO cars I don't think as they seem to be very nicely built.

I would be curious to hear what others think and if anyone has had similar experiences.

Chris

The Distance Between Inside the Wheel Flanges should be 14mm no wider.

Nev

Thanks all for the comments. I noticed once I had posted that indeed I could buy replacement wheel sets. I am going to the Eurowest this weekend and perhaps I can pick up some sets there pretty easily. Otherwise it will be back to the internet. All of my local shops (within two hour drive) are hit and miss on the Marklin stock.

Is there an item number for the wheel sets? And does anyone know what the cost is usually? A couple dollars perhaps?

In any event as it stands now, after a couple full operating sessions all is still well so I think my problem is fixed, but I will for the sake of consistency and the point regarding closing the circuit eventually replace them all with the Marklin wheel sets.

Thanks for the feedback.

Chris

Chris,

My experience is the following:

Are your Roco coaches 303mm in length (H0)? These coaches will not run at all! on R1 curves and least of all negotiate an "S" curve (in connection with turnouts). R2 curves are borderline, as long as there are no "S".

Otherwise, Roco coaches, with their original wheels, will run well on C-track. Shorter length Roco coaches will run very well even on R1.

All thanks for the suggestions and information. I have smaller wagons on my layout and as of this afternoon I have had no more problems. But I will be seeking out the wheel sets this weekend at the train show south of San Francisco just to make sure I continue to have flawless operation.

Thanks again everyone.

Chris

I would go for 13.9mm, rather than the mentioned 14.0mm.
I regauge the wheels without any special tool; One just needs a hammer and two pieces of wood with a small hole for the tip of the axle. (This is enough when all you need to do is make the spacing narrower, not wider)

Hallo from Indiana,

There is actually a fairly easy solution to the problem of ROCO cars derailing on Märklin switches due to different wheel flange sizes on ROCO than Märklin. For example, I run Märklin HO digital on K-track, but the vast majority of my rolling stock, both freight and passenger, is from ROCO.

I too once had the problem of ROCO cars derailing on K-track switches. But no more. (Now, I have never used C-track, but I hope that this remedy can also be applied to solve the problem with ROCO cars derailed on it's switches.)

The simnple solution was glueing a .020 thick, 2.6 mm wide plastic shim, from Evergreen (or Plastruct) to the wheel guide on the switch to make the space between it and the rail smaller. This very simple step ended my frustration permanently.

I have taken pictures of this but I do not know how to add a picture to this post (but would gladly do so once I learn how).

Peter Neumann

Thanks again for all of the suggestions. Since taking care to fine tune my c track as I mentioned above I haven't had any additional problems. I also purchased some AC wheel sets at Eurowest which I installed on the cars just to make sure I no longer had any problems. So all is well now on my layout.

Chris