Captain Chris, thank you very much for great help! I very grateful to you
I hope you all enjoy the knives when you receive them!
Now testing the lockback mechanism
https://youtube.com/shorts/rB-VsTYnWb4An old book from 1771 by M. Jean-Jacques Perret helped me a lot. It is in the public domain. Very interesting from the point of view of the development of the knife industry. There are wonderful illustrations at the end of the book
https://gallica.bnf.fr/ark:/12148/bpt6k10656028.texteImage