Intended to be printed with a single wall .7mm thick, no infill, no solid layers. Because the model is of the negative space, you can adjust the tolerance between the gears by adjusting the extrusion width.

In addition to configuring the extrusion width, wall thickness, infill and solid layers, you will need to make sure that your slicer always retracts when crossing internal spaces. I was not able to make the work with Cura, but Slic3r can be configured to do it by unchecking "Only retract when crossing perimeters". You will also need to make sure that you are not using wider extrusions for the first layer, which will make the gears stick together.