In this Instructable, I will teach you how to safely etch a design into glass using a vinyl mask and glass etching cream. Etching cream can be found at most craft/hobby/art supply stores or ordered online. It contains a weak preparation of hydrofluoric acid, which can be hazardous to your health, so we're going to do this safely and carefully.

The vinyl can be cut in a number of ways, but the easiest by far is to use a CNC vinyl cutter. These machines convert digital images to vector pathways and make precise cuts to create very useful vinyl cut-outs. I got mine for about $200 and I have used it for all sorts of projects. It is by far the least expensive CNC machine of any type I have used, and you can accomplish a lot with it.

Materials:

Adhesive-backed vinyl (I used Oracal 631)
Transfer tape
Masking tape
Sheet glass
Glass etchant solution (Armour Etch or similar)
Baking Soda
Warm water (for rinsing)
Glass cleaner
Denatured alcohol

Tools:

Vinyl cutter (Silhouette Cameo or similar)
Tweezers
Craft knife
paint brush or foam applicator
HDPE bucket or other rinsing container (not your sink)
Glass cutter
Stainless steel ruler or T-square

Protective gear:

Safety glasses
Nitrile or butyl rubber gloves
Long-sleeved shirt, smock, or lab coat
Respirator or mask (or really good ventilation)

Step 1: Prepare Your Vinyl Mask

To etch the glass, I used a simple vinyl mask. Vinyl is resistant to many solvents, including most acids, so it is a great choice for a masking material.

You can cut the vinyl manually using a craft knife, but the easiest way is to use a vinyl cutter. These are available from a number of retailers and made by several different companies, but any one of them will do. Which cutter you use isn’t important. What IS important is that you use high-quality adhesive-backed vinyl, because you don’t want it to come loose and ruin your etch.

Prepare your design for cutting. You will need to peel away the excess vinyl (a process called “weeding”) so take that into consideration when choosing a pattern. Simple patterns will be easier to work with than more complex ones. Fine detail can make the process more difficult. Larger designs are usually easier to handle than smaller ones. If you mess up, just start over - vinyl is cheap!

One important consideration is whether you want to make a positive or negative etch. In other words, do you want to etch the design, or do you want to etch the background behind the design? I chose to make a negative etch here, so the background will be etched while the design itself remains clear.

Once the vinyl has been cut, remove the waste until you are left with your design.

Step 2: Prepare the Glass

WARNING: Glass has sharp edges. Please be careful.

Unless you are doing a full-sheet design, you will need to cut your glass to size. This is easier than it sounds. Using a stainless steel ruler and glass cutter, scribe a single line across the glass where you want to cut it. Take only one pass with the cutter, applying firm pressure as you go. Give the scrap side of the glass a sharp tap and it should come right off. I’ve never cut glass before, but I got it on the first try. Yay!

Now you’ll want to clean the glass really, really well. Start with glass cleaner and wipe clean, then use denatured alcohol and a lint-free cloth. Allow the glass to air dry before continuing. Residual alcohol can keep the vinyl from sticking properly.

From this point on, we won’t be touching the glass. Put on some nitrile gloves before you do anything else.

Step 3: Apply Mask

Using transfer tape or masking tape, we are going to pick up the vinyl, remove it from the backing, and apply it to the glass.

Lay down the tape so that it covers the entire design and smooth it down. You can use anything to do the smoothing — a credit card would work. Then flip the design over and peel away the backing. It helps if you pull the backing away at a steep angle — it keeps the vinyl from wanting to come along for the ride.

Once you have the vinyl on the tape, apply it to the glass, being careful not to catch any air bubbles. Lay the vinyl down, starting from one side and working across, using the credit card to make sure it’s pressed down. Give the entire design a few passes with the card, pressing firmly, then peel away the transfer tape. Go slow.

At this point, you should have a piece of very clean glass with a vinyl design stuck to the front. Cool!

Step 4: PREPARE TO ETCH

The etching process is simple, but we have to do some prep first. Here's a quick safety check:

Make sure you are working in a well ventilated area.
Make sure all of your safety gear is on.
Make sure you have a clean pair of nitrile gloves on.
Make sure the brush fits into the mouth of the bottle. If it doesn’t, transfer some of the etching cream into a small HDPE container. DO NOT STORE THE ETCHING CREAM IN GLASS OR METAL, EVEN FOR A SHORT TIME. IT IS A BAD IDEA.
Make sure you have access to plenty of warm water for rinsing and an HDPE basin to rinse in.
Make sure you have access to baking soda in case of a spill.

Once you have checked all of these, it’s time…

Step 5: Etch the Glass!

This step is time-critical. Once you start, you have to finish quickly. Make sure you have everything you need before you start.

Armour-Etch works fast, so here we go:

Using the brush, apply the etching cream to the area you want to etch. Use plenty of cream — it’s cheap and you don’t want an inconsistent etch to ruin your design.

Wait 60 seconds for the etching cream to do its work.

Rinse off the etching cream completely with warm water. You can use the same brush to help remove the cream. Try not to splash.

Let the glass dry and look at your work. If you want a deeper etch, you can repeat the process.

Step 6: Cleanup and Next Steps

That’s it! You now have an etched piece of glass! Where you go from here is up to you. I used my glass sheet in a light box, which you can see in the video.

One last thing: we need to dispose of the chemicals we just used. The rinsing basin now contains a mixture of water and hydrofluoric acid. We are going to neutralize this using baking soda. Slowly add baking soda to the water until it stops fizzing. Do this outside. Do not stand over top of the bucket and breathe in. Stir with a scrap of wood or whatever you have handy that you're okay with throwing away. Once completed, you can pour this neutralized solution down the drain — it won’t hurt anything any more.

Remove the vinyl mask from the glass. You can simply peel up the vinyl. If it’s stuck too well, acetone will cause the vinyl to release.

You can use this process on any glass items - drinking glasses, plates, window panes; even mirrors will etch. The process doesn’t work well on borosilicate glass, but should work on tempered glass without issue. If you want to etch borosilicate, acrylic, or polycarbonate, you can use a vinyl mask and a sandblaster to achieve the same result with no chemical clean-up.