Home made mystery tools

[Neals]

Any idea what these are for? Largest one is 13/16. There are parts of 2 smaller ones than these.
The split portion has a pin with a spring near each end to hold them apart.

[superzstuff]

Looks like expanding lap to smooth or clean rust from a bore or hole. We used to use something like this with emory cloth wrapped around it. I guess the cotter pin could be chucked up in a hand drill and would keep tool more in line with hole like a universal joint, but too much torque would twist this off!

[Neals]

Thanks! That makes perfect sense to me