Chisel sharpening jig. By Creative Mind. 11:53 video:
https://www.youtube.com/watch?v=oW-vctjOATE
Previously:
https://www.homemadetools.net/forum/...746#post148074
https://www.homemadetools.net/forum/...176#post145696
https://www.homemadetools.net/forum/...866#post144423
https://www.homemadetools.net/forum/...273#post138650