Thanks. Lots of good info in there. My setup is pretty basic but I did leave out some things I’m doing during the process.
Acetone is used to clean the blade etc, this removes oils and helps with an even etch.
I use gloves the whole time.
I use nail polish to protect the pivot etc, then clear acetone to remove the nail polish. Don’t use coloured acetone that your wife might have as this can cause the nail polish to leave a color residue on your blade. Ask me how I know this.
I dip the blade in pure ferric chloride using a coat hanger then I dip the blade in water with baking soda mixed in to neutralize the acid. I then wipe the blade down with paper towel, this removes black smudge from the etch. I then rinse with water, dry the blade then dip again. I do this over and over until I’m satisfied with the darkness I’ve achieved.
If I etch the screws I only do the top of them by dipping them in very shallow acid so the threads don’t touch and get ruined.
I leave the nail polish on the blade when I throw it into a container with rocks for the stone wash. This protects the pivot from taking a beating as well.
On the yojimbo I didn’t want to resharpen the main bevel so I marked the upper edge of the bevel with tape, then added nail polish to the bevel and removed the tape. This ensured that the bevel didn’t get etched and would not require a sharpen. This extra step was more for my own sake, to see if it would work and it did. After the knife was reassembled all I had to do was touch up the edge with the sharpmaker instead of busting out my edge pro. Here is a pic of the nail polish and how straight I got it using painters tape.