Additive Technologies. Files for Download
Below is a list of links to various legal online sources where you can download 3D files provided free of charge by their authors.
3DLayeredscenery
https://www.3dlayeredscenery.com/product-category/freemodels/
Makers Anvil
Link for a lot of free stuff to MyMiniFactory portal:
https://www.myminifactory.com/users/MakersAnvil?show=objects&page=1&price=free