Sanding
Bring your Damascus to an 800 to 1000 grit finish. *Do not buff before etching! Buffing closes the pores in the metal, which will keep the acid from absorbing, and you’ll end up with an uneven etch.
Washing
To etch Damascus, it should be perfectly clean. Thoroughly wash your piece with acetone and pat it dry with a clean rag.
Warming the acid
If needed, warm your Muriatic acid to between 70 and 120 degrees Fahrenheit, about room temperature.
If you need to warm your acid for use, the best method is to place your container of acid into a large bowl of warm water. Never put acid in the microwave!
Submersion
With a wire, hang your damascus piece in the container of acid so that it hangs freely and doesn’t touch the bottom of the container.
To ensure that the acid penetrates, you can swish the piece back and forth in the acid, but brushing is the best way to be sure you get an even etch. Use a soft toothbrush and after 5 minutes pull the Damascus from the enchant and lightly brush over the entire surface. Repeat this again at the 5-minute mark.
Let your piece remain in the acid for 15-25 minutes, or until you achieve the depth you want.
If there are sections that you don’t want the acid to etch then you can use nail polish to mask the material. Be careful to not brush the masked area when etching so you don’t disturb the mask.
Neutralization
Remove your Damascus piece from the acid and dip it into a bath of baking soda for 10 minutes. Mix a generous amount of baking soda with distilled water to make your bath. Baking soda will settle to the bottom so make sure to mix it up well right before you drop your pieces in.
You can also use Windex (with Ammonia) for this step, but don’t try to spray your piece. Pour the windex into a container deep enough that you can completely submerge your Damascus item. Pat dry with a clean rag.
If you have masked part of your piece so that it doesn’t etch, and you want to do another round in the acid and baking soda, completely remove the mask, clean the blade, and then reapply your mask before the second etch. Skipping this step is not advisable, even if your masking still looks good, because the acid can penetrate the second time around and ruin your design.