Up until now, I’ve merely walked you through the planning and preparation stages involved with etching. Today, I’ll show you how it all pays off.

If you haven’t read through the first two parts of this series yet, I highly suggest you go back and do so:

Part 1 – Sanding & Masking

Part 2 – Graphic transfer & Touch-up

At this point you should have your enclosure ready,the graphic in place, and all spots touched-up- so that only what you want to be etched will be.

Click to enlarge

Take a match stick, snap the tip off, and break it in half. This will serve as a prop, letting the Ferric Chloride flow beneath the face of the enclosure while it sits in the solution.

Place the match stick pieces over parts that will not be etched.

Gather a glass or plastic tray (try to find one as close to the dimensions of the enclosure as possible), Ferric Chloride (available at Radio Shack and most hobby electronics stores), and that trusty pair of rubber gloves. Ferric Chloride will stain clothing and skin, will eat away at any metal, and should only be used in a well-ventilated area. Read that again. I also want to say, before the bottle’s even open, that Ferric Chloride is toxic to the environment and should be disposed of in a responsible manner! Keep used FC in a glass or plastic container and dispose of it with your city or town’s hazmat facilities.

Now that the PSA is out of the way, pour Ferric Chloride (FC from now on) into the plastic tray until it’s about 1/4″ deep.

For a normal etch, this should be plenty of FC

FC works better when warm, and there’s no need to dilute it.

Take your enclosure and place it face-down into the tray.

Pretty unexciting...

Nothing will happen, at first. Be patient- after 30-60 seconds, you should hear a fizzing sound and see some bubbles forming around the sides of the enclosure. Lift it out of the tray with your gloved hand (it’s alright if it’s warm to the touch), and check to make sure the FC is doing its job.

After about a minute in the FC

Before placing the enclosure back in, swirl the FC around in the tray to agitate it. Then let the enclosure sit for another 30 seconds.

Repeat this process (agitate FC, 30 seconds in, take out and check) for about 5 minutes. At this point, it will be hard to see if anything’s happening. Rinse the enclosure off for 30 seconds or so under cold water. As you do so, lightly brush the etched parts with a soft toothbrush to remove any metal flake. Doing this will give the FC a nice, clean surface to eat at.

Lightly brush away debris under cold water. This little step will make your etch 10 times sharper.

Return it to the acid and repeat the agitate-30 seconds in- take out and check process for another 5 minutes.

The FC bites in easier with a clean surface to work with.

Now rinse the enclosure under cold water for 2 whole minutes. This will remove and acidic residue and stop the FC from causing any further erosion. Baking Soda also works very well to neutralize the FC.

Rinse every surface thoroughly for 2 minutes.

Now for the magic.

Take 600 grit sandpaper and carefully remove the mask and paint. In a few minutes, you’ll start to see most of the detail coming through.

Be patient. Sand carefully, sand flatly.

Make sure to get the edges and corners of the enclosure’s face, and- if you need to- switch to hand-sanding to remove tough spots. In the end, you’ll have something like this:

After the etching process. Paint will give the graphic more definition.

Congrats! The hard parts are all over with, and you can stop now if you want. Some people like the pure etched look to the graphic, and in some cases it looks better than any paint. However, if you want to add clarity and definition to the graphic, or you want a color other than dark-spotty-aluminum, you’ll need to add paint. I’ll be covering this in the next part of the tutorial tomorrow.

Relax for now, go drink a beer.