BoneValley Available in HO here: https://www.shapeways.com/product/S5MZZFAGT/delorean-time-machine-train-ho-1-87
BoneValley@cbqlvr01 Yeah they roll. You just might need to lubricate the slot where the wheels fit on to the car body. And perhaps glue a thin strip of styrene on the underside of the car if you want to make sure the wheels stay on the car.
BoneValley@Bonanza_Models The car has been done commercially in HO for a lot cheaper than it would be as a 3D printed model. It's just a matter of finding the HO ones or being aware when they become available. Here's an example: http://www.bttf.net/Johnny_Lightning_Back_to_the_Future_slot_car_p/52051-1.htm
BoneValley@cbqlvr01 A BTTF 3 N scale DeLorean is now available.
BoneValley As of April 2016 I'm working on a Back to the Future 3 version of this. Balancing detail, print-ability, and paint-ability is a challenge.