How do I get the pattern back on my Damascus steel?

Grease

Grease

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May 10, 2012
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Long story made very short, I'm making my first damascus blade and need to know how to re-etch the pattern onto the part that I've been grinding away at.
 
From what I've read somewhere

Use PCB etchant from Radio Shack. Dilute to I think 6 to 1. Pull the blade out, protect the tang where you want to keep it smooth so it opens nicely, dip for 15 minutes or so, rinse. You can redip to get a bit darker but don't overdue it or there won't be any contrast. Use a bit of sandpaper on a block so you have a nice straight stroke and hit the high spots stroking from the spine toward the edge. Also I've read muriatic acid for cleaning bricks works as well and may be easier to find at a hardware store. I know lots of guys use it to acid etch blades before stonewashing to give them that industrial look. I think ferric chloride PCB etchant works better on some steels.
 
Chester gave a great suggestion.
You could also ask this in the knife makers discussion forums and other knife makers will probably have a lot of good advice.
 
I am experimenting right now with sulfamic acid. Found a thread detailing how by searching here. You can get it at Home Depot in the tile section. It was like $4 for a tub. I mixed roughly 2 Tbsp per cup of water. I'm in the trial and error process now.
 
The standard etchant is ferric chloride. It is sold by the bottle ( already mixed as a stock solution ) at radio Shack and other electronics suppliers as PCB etchant. It can be bought in bulk as a powder and mixed with water to make the stock solution. The stock solution needs to be diluted to use it. Usually 3:1 or 4:1 is the ratio ( water:FC).

Wash the blade and scrub it well with soap and water. Rinse with hot water and don't touch the blade part with bare hands ( wrap it in a clean paper towel). Mask off the tang if it isn't going to be etched. A wide tip Sharpie works perfect. Wherever the black is won't etch.
Soak in the FC tank ( glass or plastic tank) for 5-10 minutes, and remove the blade. It is OK to check it every few minutes to see the progress. It will be ugly....don't worry. Rinse off, and then gently scrub with 4/0 steel wool under running water. You can do additional etches as many times as desired to get the depth of "topography" desired and the color you like. When done, wash well and scrub with TSP or windex. This stops the etch, and neutralizes the FC. If you don't do this well, you will find rust spots in weeks/months/years to come. Dry the blade off and remove the Sharipe from the tang (if you did that) with acetone. Now, boil the blade in water for 1/2 hour. This sets the color a bit better, and removes any traces of FC. Dry the hot blade well and immediately oil it completely with a light penetrating oil. Let it sit on a cloth with the oil on it overnight. Wipe it clean in the morning, and continue with the knife project.



If you buy the powdered FC, it has to be mixed carefully. Here are some directions:
FC should be mixed to make a 42 Baume stock solution. You add one pound of crystals to 18 ounces of water to get this strength - one pound to one quart is close enough. Let it sit for a couple days. Dilute the working solution from this stock . Three parts water to one part stock is what I use.
If you are just making up one gallon, skip the stock solution and mix one gallon of water to a pound of FC powder. If making up a larger batch, one gallon of stock solution is easier to store than four gallons of working solution.

Mix outdoors and don't breath the fumes when it is dissolving. Wearing gloves and a face shield, is a good practice. Mix it in a stainless tub, or a drywall bucket. It gets hot when mixing, and will melt a soft plastic jug or bucket. It can be stored in a sturdy polyethylene jug once cooled down.
 
Stacy's info is spot on. Stacy and I both *actually do this* (as opposed to reading it somewhere) What I do is once the blade is hardened and tempered, I use the solution from Radio Shack diluted 1:1, dip for 10 minutes with agitation, rinse the sludge off and paper towel as necessary (reaction byproducts) look at the pattern repeat as necessary. When the pattern has developed to where you want it, put the blade in an old cast iron frying pan fill it halfway with water making sure the blade is completely immersed, pour in a cup or so of baking soda and boil for 20 minutes. That neutralizes the acid and sets the oxide so the black doesn't rub off

-Page
 
Awesome info here...

One other question - would it be wise to wait until after HT to etch the blade?
 
Great info here(I did a search)

I have a question about this process. I am looking to do an older stainless Spirograph blade from one of my knives to bring it back(it's really grey).

After I dip it for a few minutes and then dry it off/ rinse in water/ baking soda, will a finishing process be required to the blade to make it still look like the day it was made?
 
Re-etching a blade that is already mounted is a far greater problem than doing a bare blade after HT. If possible, disassemble the blade from the handle.

Sand the blade to as fine a finish as desired. Many take it to 2500 grit wet-or-dry. Then tape of the handle and any surfaces not wanted to be etched. Tightly taping with several layers of vinyl electrical tape works pretty well. Etch as needed to get the pattern back. In stainless damascus, it may take many 10-15 minute etches to get what you like. Go just a bit past the desired amount of etch. Wash ans scrub well, rinse very well, neutralize ( TSP or Windex), and then bring out the highlights by giving the blade a light sanding with 1000-2500 grit paper and some oil. This will make the higher surface shiny, and leave the deeper etched areas darker. Oil the blade well, and inspect regularly for any signs of rust creeping out from under the handle or elsewhere. Penetrating oils like Break or similar are best.
 
Ferric Chloride won't do much of a job on most damasteel patterns (stainless damascus). Muriatic Acid aka 30% Hydrochloric acid aka Brick Cleaner is a better product for those kind of steels.
Sometimes even ferric can be too strong. I've seen etches done with vinegar or even strong coffee for increased subtlety. It really depends on the results you want, the type of steel and the grit finish of the blade pre-etching. You probably want to do a light finishing grind/polish all over before etching because the more even the finish before you etch, the more even the finish after.
 
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