Elevator traction sheaves.
https://s3-us-west-1.amazonaws.com/h...on_sheaves.jpg
Previously:
https://www.homemadetools.net/forum/...443#post162121
https://www.homemadetools.net/forum/...632#post159240
https://www.homemadetools.net/forum/...817#post144157
https://www.homemadetools.net/forum/...834#post140346
https://www.homemadetools.net/forum/...169#post141583
https://www.homemadetools.net/forum/...676#post132966
https://www.homemadetools.net/forum/...602#post132607