A friend and I have been looking at doing wargaming, and are wanting to try it out. We have access to 3D printing and would like to use that to print our own armies, as that'd be cheaper than ordering. However, we have no idea where to start looking, as the only wargame we know of is Warhammer, and they're very protective of their IP.

Does anybody have a miniature-based wargame in a modern or sci fi setting, that's got models freely available to download and print ourselves? Larger scale fights would be preferable.