TUTORIAL TUESDAY! Etching Aluminum by Karen McGovern

Want to come over to my place to see my etchings?

I recently had a virtual conversation with Staci Louise Smith about etching.  She is going to describe her project in a later post—it’s amazing and beautiful and you all will love it.

In the course of the conversation I decided to do a tutorial on etching aluminum.  There are many ways to etch brass, copper and silver, but few options when etching aluminum.  I will be showing how to etch with ferric chloride. 

YES, ferric chloride is a caustic material that has to be disposed of in a VERY RESPONSIBLE MANNER, and yes, there are “green” etch recipes all over the web, but many do not work with aluminum.  I do have the recipe for a green etchant that works with aluminum, but haven’t tried it yet because I haven’t found a source for some of the ingredients.  When I do, I’ll be sure to post it.  This tutorial will discuss the proper handling and disposal of ferric chloride, which easily etches copper, brass and aluminum beautifully.

Etching has been around forever.  Ferric chloride historically has been used in the computer and electronics world to etch copper mother boards, among its many uses. Use the Google Machine and you will find loads of videos and tutorials on how to etch copper and brass with it.

Aluminum is a whole other ball game.  If you were/are into crazy science experiments, you will love etching aluminum.  It’s FAST (less than two minutes usually) and a bit scary (can you say CHEMICAL REACTION?), and the results are pretty great.

Aluminum will not patina conventionally like other metals.  By its very nature it will not rust, tarnish or discolor. Coloring this material is difficult using conventional methods and requires effort to keep the color you achieve if you use inks, dye patinas, etc.  Ferric chloride will permanently color and etch aluminum in a dreamy, monochromatic way.  Let’s give it a go, shall we????

First, the scary disclaimers and safety stuff:

1.    WORK IN A VENTILATED AREA, LIKE OUTDOORS.  For real.  Do not use ferric chloride in a room without TONS of ventilation because, HYDROGEN GAS.  Hydrogen gas is NOT TOXIC, and a small amount is produced when you etch aluminum with ferric chloride and it is pretty startling the first few times you do this.  EXCITED YET?  I etch in my garage with the doors wide open.

2   Use rubber gloves (I use surgical gloves which you can get at any pharmacy) because you will be handling the ferric chloride coated metal more than you would etching copper or brass.  Ferric chloride won’t burn you on contact or anything like that, but it isn't the best thing to have on your skin for prolonged periods and it does stain EVERYTHING (clothes, counter-tops, concrete, you name it) so bear that in mind.

3.   Wear a mask if you have one, just to be extra safe. You can find bulk, inexpensive  disposable painter’s masks at any hardware store.

4.      Wear safety glasses.  YOU DO NOT WANT FERRIC CHLORIDE IN YOUR EYES!!!

5.     Spent and neutralized ferric chloride must be stored properly and disposed of at a recycling center in the same manner spent oil from your car is recycled.  I keep a few empty plastic jugs in my garage, fill them with spent FC using a plastic funnel, and then take them to my local recycling center when full.  FC must be kept in plastic containers!

My FC storage jug.

 Okay, terrified yet?  Don’t be.  FC is scarier sounding that it is.  I promise.

What you’ll need:

Aluminum bracelet blanks.  I get mine from Gotta Get A Deal on Etsy.

Ferric chloride.  I get mine from Allied Electronics, but you can also find it at places like Radio Shack or other electronic supply stores. (Note: When you get it, take a few minutes to read the information that comes with it.  Familiarize yourself with this liquid as much as you can prior to use.)

Three empty plastic containers with lids large enough for your blank to sit in.

Packing tape

Sharpie marker and/or Staze On Ink (Michaels Crafts)

Rubber stamps of your choice (Michaels)

Sanding sponges and polishing cloths

Newspaper

Baking soda

Old towel or washcloth

Here we go!  Cover your work space with newspaper.  It is nice to have a sink nearby just for easy access to water.  When I etch with aluminum I set up right next to my shop sink in the garage.  The sink itself is heavy plastic and meant for grungy work.  Fill one plastic container with fresh water, one with enough FC to cover your bracelet blank, and leave one empty.  You don’t need to fill the container with FC, just a couple inches in the bottom so that you can immerse the aluminum easily.  Set them up in a row--FC, plain water, then the empty container.

I have found that these Band Aid plastic containers are perfect for etching cuffs!
Left to right, FC, water, and empty container.  Baking soda ready to go!

Clean your bracelet blank using a sanding sponge or fine steel wool. Stamp or draw a pattern with Staze On ink or a Sharpie, let dry completely.  Cover the back of the bracelet blank with packing tape, leaving a long tail on either end.  Fold over a bit of tape on either end to act as “handles” so you can easily dip and lift the bracelet blank in and out of the FC.  Be sure the tape is flat and covers the back of the blank completely.  Use a pen or chopstick to burnish the tape to the back.  You do not want any FC getting under the blank!

Put on your rubber gloves. Hold the tape by either end and immerse the blank, stamped side UP, into the FC, covering completely.  Immediately lift it out of the FC, holding it over the container.  LET THE FIZZING BEGIN!!!  FC reacts instantly with aluminum.  The fizz is the production and release of harmless but kind of scary hydrogen gas.  You will smell it and the metal will actually get warm. I count to between 20-25 seconds in my head..  Basically I wait until the surface of the metal begins to really fizz and the metal gets warm. Immerse the aluminum in the container of clean water.  Lift out immediately, and immerse in the FC again, lifting out right away.  FIZZZZZZZ, count to 20 or o, then dunk in the clean water container.  I do this three or four times depending on the thickness of the aluminum, which will turn BLACK at this point.  Run your gloved finger over the design, you will feel it when it is etched enough.  FC will LITERALLY DISSOLVE ALUMINUM.  I learned this the hard way the first time I etched aluminum.  I left the blank in the FC like you would copper or brass (around 20 MINUTES) because I was too impatient to actually READ ABOUT THE PROCESS.  When I came back I pulled up the tape and THERE WAS NOTHING THERE.  Just a foamy pile of goo on the surface of the FC.  SMH.  Stupid. 

Here are a couple videos of the process. In the first video you will see that I dipped the blank a couple times in the FC to get the FIZZ started. I was using fresh FC and it took a few seconds to "bite" the metal and begin the process.

Anyway, at this point you will say to yourself, “What have I done?” because the aluminum will be a dull, deep black and look ruined.  FEAR NOT!  Place it in the empty plastic container and dump some baking soda on it to completely neutralize the FC.  Some fizzing will occur.  Rinse it in the sink under running water.  You have neutralized the FC on the metal with the baking soda, so it is now harmless and can go down the drain as you rinse. I keep a bristle scrub brush in my sink and use it to scrub the surface of the metal, the black will go away as you scrub.  You can also use a soft wet/dry sanding sponge here. You want all the black to be gone, and the etched surface to begin to shine. Rinse well, remove and discard the packing tape. You can also take your gloves off now.

Now for the REVEAL.  Dry the metal. Using a very fine grit sanding sponge, clean the surface of the blank.  The black is gone, and your stamped pattern will shine up beautifully. Anywhere the etchant touched will now be a matte misty grey.  Once you have revealed the etched pattern, you can then polish with a polishing cloth.  Bend the cuff using your handy dandy bracelet bender or a bracelet mandrel and you are DONE!!!  I use a steel bracelet bender from Gotta Get A Deal in my vise. Bends a cuff into the perfect oval shape in SECONDS. I love this thing.

Cool!!!  As you can see, I chose a wheat pattern stamp for this cuff.  TIP: I went over the stamped image with a fine line Sharpie, filling in any areas I wanted darker, or that I missed when I stamped the blank. 

Voila!

Now, you do not have to dispose of all of your FC every time you use it.  The container holding just FC can be closed and saved to use again and again. It is good for multiple etchings.  You will know when it is spent when it takes longer and longer to actually etch.  At that point I dump in some baking soda,then dump the mix into a plastic jug.  You do need to neutralize and dispose the water you used to dunk the bracelet in as you etched.  Add some baking soda and pour this into your storage/recycle jug with any other spent FC.  Seal the jug and keep in the garage until it’s full (which will take a long time unless you etch a million things a day).  When the jugs are full take to a recycling center that also accepts things like paint, oil, etc.

Now, I promised that I would give away the cuff that I created for this tutorial.  Okay, here’s the deal.  You can win this cuff by posting a comment here about the scariest technique you mastered in your artistic journey.  Did you learn how to use a torch even though you are terrified you will burn your house down?  Spend your last buck on a kiln because you JUST HAD TO LEARN HOW TO MAKE CERAMIC BEADS?  Whatever it is, post it here and I will use some sort of computer program to randomly pick a winner on FRIDAY, FEB 27th.  Oh, AND SHARE THIS BLOG POST, OKAY??? Thanks. And good luck.  And don’t be afraid of etching, or kilns, or torches, or anything that stands between you and your artistic dreams.  Read, research, and DO IT. Now, GO MAKE SOMETHING AMAZING!