I recently purchased two “Heavy Weight” Con-Cor Branchline-Commuter-Suburban Cars, a Combine Car and a Baggage-Mail Car.
I noticed that the Combine Car, which is trailing, derails after coming out of 18" curves on my Kato Unitrack layout. It’s always the trailing truck regardless of which end is forward.
After observation I noticed it’s due to the top of the forward end of the truck on the outside of the curve that catches on a cross member on the undercarriage and won’t allow the truck to straighten after coming out of the curve.
I was thinking of adding a washer where the truck is mounted to lower it slightly from the under carriage. Has anyone else here encountered this problem, and if so, how did you deal with it?
Even though these cars should negociate the 18" that’s the absolute mininum. The truck/ wheel interferance to undercarriage frame can be cured by removing some of the underframe. I would also add some weight or interiors or both. Do check the coupler height to see that the body isn’t riding to low, but I doubt this is the case. If the interferance is that slight that it can be solved by the washer thickness, that’s not much material to cut or file off.
I had considered filing some material off the undercarriage but I hesitate to do so on a brand new car. I have to look around for some washers of the correct thickness and diameter and I will try that.
Sometimes the blade is the answer. I have about a dozen Exactrail FMC 4000 gondola and I had two that would derail on 22 inch curves and looking at what was happening it was the wheels hitting some the detailing on the bottom. It look like the lines on the underside where just a hair bit off on their assembly. So I just nipped the line where the wheel was hitting it and all is good and from the side view you cannot even tell.
I tried the Kadee washers as suggested by JR and they worked! The inside diameter of the washer was a little small but I just forced them on over the shaft on the bottom of the car that fits onto the truck.
How are the couplers mounted on this car? If they are truck-mounted, that’s OK, but if they are body-mounted then you have raised the couplers up by the thickness of the washer. It may not seem like much, but as time goes on you may have trouble keeping the cars together.
You may be able to fix this by putting a similar thickness of material between the car body and the coupler box, if it’s removeable. Use a coupler height gauge to make sure the coupler is still at the right height.
There are good suggestions regarding possible corrections to the cars.
Look at the track, too. Does the track abruptly change from 18" to straight track? That would be a problem. The track should gradually made a transition from tangent (straight) track to the minimum radius.
Also, look carefully at every rail joint. There should be no kinks from side-to-side or up and down. Hold a straight edge against each rail joint to check.
Glad the advice paid off. I have a few Concor cars and this was the easiest fix. When using the Kadee fiber washers if the are a bit tight you can cut one side with a scissor and they will fit over the mounting pins easier and work just fine.
Welcome to the wonderful world of too long passenger cars on too small radii curves! I think we have all been there at one time or another. The only “common” cars that work reliably on 18 inch curves is likely to be Athearn - with are “shorties”. The pretty much scale length IHC, Rivorossi, Concor, Walthers, etc. are just not made to go thru 18 inch curves.
But, you want to fix the problem and your best bet is to carefully cut away what is binding the truck - either cutting from the truck itself or preferrably the car frame, and then touching it up with the proper paint. I’ve had to do this with some Walthers cars for the one 26 1/2 inch curve on my layout.
Raising the car with a washer certainly may solve your problem, but it will hurt coupler height and would likely look “funny”. Of course if you don’t have to raise it but a 1/16 or so, you can probably get away with it.
Gotta say, the real solution is to redo your curves, and 22 inch should work well for the Concors and look a lot better too.
When I’ve run into cars that the Kadee washers didn’t quite fit, I cut one side with a hobby knife. This allows them to spread slightly and lie flush against the bolster.
If I were you, I would still add weight over each truck to ensure that the cars hold the rails.
With Con-Cor cars, derailments and uncouplings are common until refinements are made in terms of weight, body mount couplers, and the addition of metal wheels.
Hmm. I bought a set for exactly the same reason. I have yet to try them out, but guess I had better get at it as it will be a BIG HUGE Disappointmet if they don’t “comfortaby negotiate 18"r curves”…as my largest curves are 18"r.