Chainsaw knife. By Selfmade. 12:07 video:
https://www.youtube.com/watch?v=88lIPsWSstE
Previously:
https://www.homemadetools.net/forum/...860#post167671
https://www.homemadetools.net/forum/...080#post164891
https://www.homemadetools.net/forum/...993#post164497
https://www.homemadetools.net/forum/...258#post154090
https://www.homemadetools.net/forum/...466#post122599
https://www.homemadetools.net/forum/...959#post148917