So you would like to 3D print your own Star Wars characters? There are plenty of sites that provide you with object files and printing instructions for them. USWaterRockets has shared downloadable object files for a 3D printable Star Wars Astromech Droid. It is nearly 1/4 scale and can be printed using any machine capable of printing 120x120x120mm models.
You can follow more information about this project here.