Simple basic beam lifting clamps

[Frank S]

For anyone going to copy these, be aware these wouldn't be good for heavy loads without something to keep them closed. For general shop use they're fine with some care in use.

Common would be running thread run through both sides and a spacer at the bottom so you can snug them up to the beam. This way it doesn't fall off right when you have your head under the load.

Here's a commercial clamp for ideas...

Your looking at it upside down the clamps at not for hanging under the beam they are lifting the beam the weight of the beam plus the curvature of the loop maks them next to impossible to come unhooked while lifting
as you can see they will not come unhooked even when the beam rolls over while lifting