Photographs aren't human-made either, yet they are copyrightable. I agree that both the letter and the spirit of copyright law are in favor of models not being copyrightable, but it will take years until there's a court ruling either way. Until then proceed with caution and expect rights holders to pretend like copyright does apply. Not that they will come after your home setup either way.
Photos involve creativity. Photos that don't involve creativity aren't usually considered copyrightable by the courts (hence why all copyright cases I followed include arguments that establish why creativity was a material to creating the work).
Weights, on the other hand, are a product of a purely mechanical process. Sure, the process itself required creativity as did the composition of data, but the creation of the weights themselves do not.
