Acid Etching Metal | DIY Acid Etching | Online Metals (2024)

Your piece must be completely clean before it can be etched. Oils, tarnish, or other chemicals will negatively impact how well the etching works. First, make sure that the edges of the piece are filed down and not sharp. Then make sure the surface is prepped. There are a few methods you can use here.

The easiest is to soak the piece in acetone. This is quick and simple, but sometimes certain tarnishes can survive the acetone bath.

You can also scrub the piece down with a Brillo pad or some other sort of abrasive scrubbing pad. This will leave a brushed finish on your surface that will impact how the final piece looks. Some people love that and use this method specifically to get that different finish. Other people dislike it and generally choose the third method.

For that, use a normal sponge and an abrasive cleaner like Penny Brite or Bar Keepers Friend to clean the piece. This will give you an even and polished finish.

Other than designing your pattern, applying the resist is the step that is most open to personal interpretation.

First, the material you choose as a resist is very open ended. There are numerous inks specifically designed for etching that you can use. There are also more easily found materials you may already have around your house! Permanent marker ink, like a Sharpie, works well as a resist. Nail Polish and even masking tape also work well. Back in my high school chemistry class we made ornaments using masking tape as a resist.

Once you have your resist chosen, you need to apply it. The two main methods here are to cover the entire piece with the resist, or only cover part of it. In the images we’re using here of Bryn Gleason, you see she covers the entire plate in the resist. Other people, especially folks' acid etching knives, will only cover certain parts of their pieces with a resist. It all really depends on how much of the material you want to be etched.

Once you have decided that, apply the resist. Make sure the edges and backs are also covered. If you are etching a knife, make sure that the beveled edge of the blade is covered. Apply with sponges, cotton swabs, nail polish brushes, or just draw it on. Whatever your resist is, apply it in the most appropriate method.

If the application of your resist is the pattern, skip to Step 5.

But if not, now is the time to make your design. If your resist is ink or wax, use a tool to scrape away the image that you want. You can see an example of this in the picture below. If you used masking tape draw your design on the tape and then cut away those portions you want to be etched.

Here’s where you really can let your creativity shine!

First, make sure that your PPE is on. Next, you’ll want to suspend your piece in the acid bath. There are three main methods to this, and they largely depend on what you are making.

The method you choose to suspend your metal in the acid bath is the most complicated part of this entire process.

Suspension Method:

Once you’ve got the piece etched to your satisfaction, pull the piece out and put it in the acid neutralizing bath of water and baking soda. A reminder, that bath is a 1:1 ratio of water to baking soda.

The bath will fizzle a bit, which is fine. Let it sit for a minute or so. Then, take a toothbrush with baking soda on it and scrub any deep portions of the piece. This will help make sure all the acid is gone.

Next, once the acid is fully neutralized, rinse off the baking soda with water.

Lastly, remove the resist from your piece. Acetone generally works well for that.

At this point if you so desire and are working with copper, you can apply a patina. To do this, just apply some liver of sulfur where you want the patina. For copper, this will create a black or dark brown patina. Many artists apply this to the recessed areas of their pieces then wipe and clean the elevated parts of the metal. The process creates a sharp relief to highlight your work.

Congratulations! You have successfully completed your first acid etching!

Concerns about the health effects of long-term exposure to acids and solvents caused research into less toxic etching methods. One etching system uses acrylic polymer as ground and ferric chloride for etching. The polymers are removed with sodium carbonate (washing soda) solution, rather than solvents. Acrylic polymer etching can also be done successfully on softer metals such as aluminum sheet.

Saltwater etching is another alternative method that can be done with household ingredients, and on the cheap! However, while the ingredients are mild this method does produce toxic gas that should not be breathed in. So, exercise caution! Make sure that you have proper ventilation and some sort of mask to prevent inhalation of the fumes.