I spotted this design and printed it out only to find it was to big for my lathe.
I performed some changes in CAD and it now works well on my mini lathe.
It will require one 30mm o/d x 10mm I/d x 9mm thick bearing.
AM-Tech P4820 line level from Amazon (cheap and easy to take apart ).
One 10mm piece of silver steel.
6mm and 4mm screws the circlips are optional