These cars look nice but there are several issues that keep you from just putting them on the track and enjoy running them.
1) Cars wobble back and forth as they roll.
2) Cars won't couple unless lots of force is used.
3) Wheelsets aren't in gauge.
4) Wheelsets fall out of trucks.
I will show fixes for all of these.
1) The wobble appears to come from loose trucks. The pins are installed fully but there is still too much play for the truck to fit correctly close to the body. I just removed the truck pin and shortened it a little. Now the truck is held closer to the frame and the little pins that are designed to limit wobble have a chance to work.
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2) I will say that I am not impressed with the trucks, couplers or wheelsets on these cars and I will probably makes changes but you can make them work to be at least runable. There are several issues that cause problems with the coupling.
a) Flash. The biggest issue is there is flash in the female part of the knuckle which keeps the trip pin from moving easily and allowing the coupler to open.
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After the flash is cleaned out it should look like this:
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When reassembling the coupler, don't tighten the screw too tight or the coupler won't swing at all.
b) The hole in the coupler halves that rotate on the post in the draft gear sometimes needs to be filed a little bigger to allow the coupler to swing more freely.
c) The trip pin is sometimes installed incorrectly. It can be sticking straight out instead of angled to the side, which makes the trip pins hit and keep the cars from coupling.
d) The centering pins don't always hold the coupler in the center. Not much you can do about this one without replacing the coupler.
3) The wheelsets are almost all too narrow. They hop through frogs on Atlas code 55 switches. I regauged some of them but I am not happy with how well they stay in gauge. Fox Valley wheels take care of this nicely and look better.
4) Several trucks have the side frames bent outward. The side frames are very thin. I bent them back straight but time will tell if they stay straight.
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The outer wheelset is barely hanging in there. Note the trip pin is also straight and not angled.
I will probably convert them to z-scale couplers and maybe change out the trucks down the road, but at least with these tweaks they can be run. Kind of crappy that you have to do all this work just to run a $40 car.