Damascus etching

[Tyler Reinarts]

How are you supposed to etch a damascus blade so you get some contrast between the steels? Im trying to etch one made of 15n20 and 1095 (de-greasing then submerging in ferric chloride in distilled water at a 4:1 ratio for 30 min) but by the time I've neutralized it and washed off all the black silt the 15n20 is just as dark as the 1095. Then I tried sending the high spots with 1500 grit sandpaper and that just brightens up both steels. You can clearly see the layers, but except for at the weld seams it's all the same color and texture. On every other damascus knife I've seen there's a clear color difference in the layers. I've heard that if your blade isn't hardened right it can mess this up but I know mine is. Any idea what I'm doing wrong?

[Alex Middleton]

How many soaks in the ferric have you done?  How many layers is your damascus? Are you using a hard backer when you sand with the 1500 grit paper?

I've had good luck with 4 or 5 15 minute soaks in ferric and then follow that up with an overnight soak in concentrated instant coffee.  This method, followed by a very light sanding with 1500 or 2000 grit paper using a steel backer has worked well for me on higher layer count blades.  I had problems similar to yours with lower layer counts and ended up doing multiple coffee soaks before it looked good enough.

[Alan Longmire]

I suspect your statement "washing off all the black silt" is the biggest problem.  You don't want to get it all off, just the part that's on the 15N20.  Once you've etched, and Alex's suggestion of several short soaks, wiping off the loose oxides in between, is a good one, you should have some topography.  On the last etch, after neutralizing, you can boil the blade to "set" the oxides in the deeper grooves (the 1095), and then polish the high spots (the 15N20) with your finest sandpaper on a hard backing.  Or you can dip it in water and boil it off with a torch a few times, that does the same thing.  The coffee treatment really brings out the contrast if you want it strong.  The key to all this is the hard backing.  If you just rub with handheld paper or steel wool, you're polishing the whole surface and erasing the etch.  

[Tyler Reinarts]

Thank you both.  I'll give your suggestions a try.   

[John N]

I do multiple short etches (5 mins ish), scrubbed with a pan scourer and dish soap in between (like my american lingo ?  ) When you can just about feel a bit of topography stop and clean it up. You can always etch more after if you dont like the effect.

Im not into this 'setting the oxides' thing, I like to know all scuz has gone from the blade as I mostly do chefs knives. I sand with 1000g wet and dry on a hard backing to hit the high spots, and thats what makes it pop. Also hit it with some flitz or metal polish, on a piece of leather glued to a hard backing.

One observation I have is that blades look different 'in the hand' to the photographs people post on line. In my experience, sometimes the shiny Ni. layers look like the 'black' layers in a photo as they are reflecting something dark. The one below in the photo looks way more contrasted in the pics than it does in the hand. (the photo is straight from my phone, no editing)

Edited September 28, 2019 by John N