We needed a grate in the 1st floor apartment that would swing open for access to a maintenance shaft, but we could also close and lock to keep the tenants from climbing in the shaft and gaining access to the other apartments in the building.
It had to be a grate because the shaft also doubles as the cooking flue, to take all of the cooking smoke out of the apartments.
Made from 12mm rebar. We will drill holes around the shaft entrance and drive in rebar pegs, then weld the grate to the pegs.
For a first-timer, not too shabby. And not a bad skill to learn. Welding can be really useful around here.