This is a quick guide as to how I etch my damascus steel. It's not the only way. There are lots of ways and if they work they are correct. This is how I do it and it works for me.
I'm not going to cover how to make damascus steel, there's lots of information online and it's pretty simple. Essentially you forge weld 2 contrasting types of steel (I used 15N20 and 75Ni8) then manipulate it to make a pattern. I did a simple twist as I like the way it looks. Then etch it to make the pattern visible.
Here we go then...
Step 1: What You Need
Some damascus steel
Etchant - Ferric Chloride (strength 42 baume)
Glass or plastic containers
Extra fine (000) steel wool
Wire (to hang piece in acid)
Bucket of water
oil (I used olive oil as the knife will be used on food)
Step 2: Clean
Make sure your steel is clean. Very clean.
Once it's clean put on your gloves and do not touch it with your bare hands until the whole process is complete.
Dip it in acetone and allow to dry.
Step 3: Acid Bath Thriller
Mix your Ferric Chloride 1 part to 3 parts of distilled water and put in suitable container. I label mine so that can remember what the hell it is next time I'm in the shed...
Suspend your piece in the acid. After 10 minutes take it out and give it a quick dip in the bucket of water.
Step 4: Scrub
Scrub it with the steel wool until you've got rid of the oxides. The pattern should be looking good.
Dip it in the bucket of water.
Is the pattern deep enough? If not, dip it in the acetone (see lovely photo) then repeat the previous step until you're happy.
The knife in the photo had 3 ten minute dips.
Step 5: More of the Same
When you are happy with how deep the etch is and have done the final scrubbing, dip it in the acetone, allow to dry then give it another 3 minutes or so in the acid to get the final finish.
Be extra careful at this stage not to touch it!
Dunk it in the acetone again then allow to dry. Acetone dries very quickly, so hanging it up here was completely unnecessary but allowed me to put another photo in...
Step 6: Bake and Shake
Put a tablespoon or so of baking powder in a saucepan of water and boil the piece for 10 minutes. Apparently this neutralises the piece as well as helping to set the oxides.
Step 7: Oil It, Don't Spoil It
You can use some 2000 grit sandpaper at this stage to very lightly sand it to bring out the shine on the shiny steel.
As soon as you're done, oil it. It will rust almost immediately if you don't
You could use clear coat lacquer instead if you like.