Steel ruler marking gauge. By Mistry MakeTool. 6:24 video:
https://www.youtube.com/watch?v=H82rCfttqF8
Previously:
https://www.homemadetools.net/forum/...399#post169696
https://www.homemadetools.net/forum/...547#post166700
https://www.homemadetools.net/forum/...008#post164540
https://www.homemadetools.net/forum/...030#post160598
https://www.homemadetools.net/forum/...609#post151690
https://www.homemadetools.net/forum/...512#post151282
https://www.homemadetools.net/forum/...426#post146797
https://www.homemadetools.net/forum/...746#post148074
https://www.homemadetools.net/forum/...508#post147175
