Homemade chisel sharpening jig. By Mistry MakeTool. 5:21 video:
https://www.youtube.com/watch?v=ruDgP6-lW-I
Previously:
https://www.homemadetools.net/forum/...176#post145696
https://www.homemadetools.net/forum/...866#post144423
https://www.homemadetools.net/forum/...273#post138650