About this 3D model

My first model. It is based on one of my kid's train tracks. I've tried to parameterize it. The train_track module takes a parameter to determine the length of the track. There are also variables for other aspect of the track. Any feedback is appreciated! I think I may still need to work on the connectors, maybe give a little wiggle room to make them fit better. I made a bit of a post about this here: http://objectaday.blogspot.com/2012/07/first-object-train-tracks.html