Magnetic dovetail block. By J-woodworking. 11:36 video:
https://www.youtube.com/watch?v=5fQVlkSOF64
Previously:
https://www.homemadetools.net/forum/...569#post185843
https://www.homemadetools.net/forum/...237#post184815
https://www.homemadetools.net/forum/...158#post180423
https://www.homemadetools.net/forum/...872#post179256
