Make sure there is no wax or oil on the blade. Solvent or even Dawn detergent works sometimes (no finger oil on the blade). Add 3-4 parts very warm or hot tap water (as opposed to boiling water) to the etchant. Is there scale on the blade--you have to sand it off. Etch for only 15 or so minutes (watch it to see the pattern come out) at a time. Sand lightly with fine wet paper on a hard rubber backing (for concave areas) or flat block for flat areas. You don't want to sand through all layers and lose your contrast. 4/0 steel wool works too (lightly). Repeat, watch it--more or less time may be required for the look you want. Rinse with water/baking soda solution before you sand. Sometimes I set a hot water warmed blade in very shallow hot water in a small frozen entree dish and gently pour full strength etchant over the blade lengh-- instant etch. Flip it over and do the other side. There are rules about not adding acid to water or vice versa I forget which, but I've never had it react, probably because it's a weak acid. IT IS NEVERTHELESS AN ACID SO PROTECT YOUR SKIN AND EYES! I learned most of this from Wayne Goddard's writings--check them out. There are no doubt many other methods used successfully---???
[This message has been edited by RARanney (edited 06-24-2001).]
I etched this Devin Thomas raindrop damascus in ferric chloride. I held it in the straight acid, no cut, and kept it moving around for 30 seconds, took it out and dipped it in water with bakng soda then cleaned it and did another 30 seconds in the ferric chloride. In person it looks like it was blued. http://members.aol.com/l6steel/damascusblade.jpg
Take care!! Michael
Always think of your fellow knife makers as partners in the search for the perfect blade, not as people trying to compete with you and your work!
Here are the etching instructions that we publish. I hope it helps.
Etching Instructions for Thunderforged(tm) Damascus
Step by Step
1. Clean blade with acetone.
2. Soak in solution.
3. Rinse in water & soap.
Clean your blade very well in acetone. At this point make sure you do not touch the blade with your hands, as the oils from your fingers will harm the end result. We recommend that you use tweezers. Once the blade is totally dry you are ready to dip it in to the solution.
Dip the blade point down in to the glass or plastic container that is holding the etching solution. Leave the blade in there for about 15 to 20 minutes. Pull the blade out after 15 minutes & inspect how the etch looks, if you need a higher contrast, again dip the blade back in the etching solution for additional time till you have reached the desired contrast. Do regularly check on your blade while in the solution.
Once you have reached the desired contrast you pull the blade out and immediately rinse it in luke warm water & rub hand soap on it simultaneously. At this time you will notice that a black substance will be coming off, this is the carbon that was removed during the etch. Keep washing the blade until no more black carbon is coming off.
The next step is to oil your blade using good quality gun oil.
Even after you have oiled it, you can go back to step 1 to start all over to reach a higher contrast if desired.
Etching Solution Ingredients
50% PCB Etchant Solution (available at Radio Shack®) & mix with 50% White Vinegar. Use a plastic or glass container to hold this solution DO NOT use a metal container.
If you were to leave the blade in solution for a long time could you achieve a really gnarly and ancient look? That seems like something to play around with depending on the pattern and blade style....