Trapdoor hinge

This hinge is designed for a trapdoor or a cellar door. It allows it to be completely flush with the floor with almost no clearance around, yet open and close freely. The stl files are probably not going to be very useful, see .x_t

animation: https://www.youtube.com/watch?v=KpsRPT7j6Bc
https://www.youtube.com/watch?v=vNUF3juJ4NM