I am printing the track on a reprap. with a 25% infill and 0.4mm nozzle, 0.2mm layer height. Material is ABS. Somewhere after the 3 cm height a couple of fractures occurred in the archways. That area of the print lifted up and compressed some of the support above that, but didn't affect the track, so I am allowing the print to continue.
I guess I should have stuck with PLA. The stresses that build up in an ABS print are just too much. I am slicing with Cura, it does not allow for a "high skirt" to stop drafts that I know of. If it finishes I will post the pics including the cracks.