Just built my first HO scale train (right now a circle due to not enough space), it's part of a set...the Santa Fe Flyer. I also got a couple of flat cars and a gradient.

Is there a real heavy freight car? (perhaps a steel one) I want to load it with a real heavy freight car or even an heavy item and see it climb that gradient. Everytime I put a book or other heavy item, when it tries to go around the curve at medium speed..it derails.