Problems unique to Marklin 4 axle tank wagons ?

I'm building a fairly ambitious Z scale layout. Probably too ambitious seeing as it's my first.

I have finally reached the point where I can run trains. I use Wright turnouts for the standard switches and Marklin double slips.

I am experiencing frequent derailment on one particular Wright turnout and on one particular Marklin double slip.

The strange thing is that it is only Marklin 4 axle tank wagons that derail. Locomotives, other 4 axle wagons and 2 axle wagons are all fine.

Before I undertake the rather involved step of changing out these two switches any input on what could be causing this would be appreciated. Thanks in advance.

The problem is obviously not related to the brand of turnout, and I must say I haven't experienced that problem with 4-axle tank wagons in particular. It might be that they have a lower weight to size ratio, but I couldn't be sure about that.

Advice I was given, and which I haven't tried out yet, is to file the point of the switch rails so that they fit closer against the stock rails. Then rolling stock and loks will be less likely to "pick" the turnout.

The double slips are notoriously problematic. Lets focus a bit more on the turnout and the cars.

The Marklin 4 axles cars are very light compared to other Marklin cars. If you have seeing this problem on only one turnout, you may be able to tweak the turnout slightly to allow the lighter 4 axle cars to transverse correctly. First push the car slowly into the turnout to see if you can determine the exact point the cars derail. There may be a dip in the rail that it causing the problem. Make sure the turnout is level and not moving. If it is not secure, a little vertical movement may be enough to derail the car. Also look at ever so slightly shimming one side of the turnout or the other. For instance, if the car always derails to the inside, try shimming the inside of the turnout slightly. See if this solve the issue. The turnout may be sitting at an angle at such a way that the cars will derail.

Other tests you can do is tape a dime on the car (or other weight) and run it through the turnout. Likely it will go through fine. There are just a some very minute factors at play that is causing your issue. Weighing the car may also solve the issue, but if you are a collect, you will not want to modify the Makrlin car. I always recommend trying to solve the issue at the track level since if it happen to one car type, it very well may happen to another car type down the road. Solving it for one type may actually provide a long term solution.

As for the double slips, again these are problematic. I really don't have any tip for you on these. I have purposely avoided them in my track plans and relegate them to branch lines or little used track sections.

Rob

Thanks for your replies. Very useful. Don't think it's the wagons. I turned out to have problems with a lot of other wagons. I think the turnout isn't perfect and I'm going to substitute another but the main problem I think is that the grading isn't quite right. I'm currently rebuilding the whole trackbed. I'll see how it goes then. Shimming didn't solve it.

Also I'm redesigning my layout without the doubleslips. I've had trouble with more than one of those now and who needs it?

Hopefully this will solve the problems. Hope so. Thanks.

I've no experience with this kind of stuff but as Rob said I guess these 4-axle cars (wagons for you Brits) are very, very light. First maybe could try to add some weight to them?

Dom