Chemicals That Etch Glass
I am often asked what chemicals are used to etch glass. One of my favourites that often comes up is “can I etch glass with vinegar?” NO, you cannot etch glass with vinegar! I mean, just look at the bottle it comes in!
There are a number of acids, caustic and abrasive substances that are used to etch glass. However, many of them are extremely hazardous and would not typically be used in a home or hobbyist setting. The primary chemicals that etch glass and are commonly used in industrial or professional settings are hydrofluroric and hexaflurosilicic acids. But there are safer options for at-home use.
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Hydrofluoric and Hexafluorosilicic Acid
Generally, hydrofluoric acid is used to etch glass. But, hydrofluoric acid is extremely reactive so is typically only seen in industrial factories or professional businesses where the proper precautions can be taken and specialist preparation environments constructed.
Hydrofluoric acid is a highly corrosive liquid as well as a strong contact poison. It can even penetrate tissue and poisoning can occur rapidly through exposure to skin or eyes or even when inhaled or swallowed. Personally, I wouldn’t even want to be near an open container of hydrofluoric acid. The scary thing about coming into contact with hydrofluoric acid is the reaction is often delayed. The burn may not even be painful initially! Therefore the hydrofluoric acid glass etching process is far more onerous given the amount of precautions that need to be taken.
A slightly less dangerous, inorganic compound, called hexafluorosilicic acid (H2SiF6) is often used. Whilst hexafluorosilicic is interestingly produced naturally in large quantities inside volcanoes, it is manufactured as a coproduct in the production of phosphate fertilizers.
Even hexafluorosilicic can be dangerous though, so often abrasive methods (sand blasting, engraving, scribing) are used instead of etching with chemicals.
Glass Etching at Home
For hobbyists looking to achieve a professional-looking result at home without needing to set up a laboratory or fume extraction station, there are two primary methods for achieving a great etched glass result.
Small glass etching jobs
There’s probably only one product I would recommend for etching or frosting glass at home and that is Armour Etch Cream by Armour Products.
This glass etching cream contains barium sulfate, sulphuric acid, sodium bifluoride and ammonium bifluoride. It’s fast acting and specially formulated for hobbyists to obtain a permanent glass etching on all sorts of glass objects including drinking glasses, windows and mirrors. Keep in mind though, that it will not etch Pyrex glass, acrylic or plastics. You also wouldn’t use it on large areas of glass (see below for that). It’s definitely more of a hobbyist product.
Whilst Armour Etch is great for home glass etching projects, because of the chemicals it contains you still want to exercise plenty of caution when using it. You should ensure you;
- Keep away from eyes and skin
- Wear new butyl rubber, Teflon, Viton, Saranex or Responder gloves
- Wear fully enclosed safety glasses
- Where possible use the product outdoors or in well-ventilated areas
- Know your local health advisory service phone numbers if contact does occur
You should keep in mind that etching creams like Armour Etch and not intended for anything larger than a 1″ x 1″ surface area. Whilst I’ve successfully used the cream on larger areas, you would never try to use it on whole panes of glass. For that, you would typically use an etching bath solution.
Medium glass etching jobs
If you’re wanting to etch patterns onto slightly larger areas such as a pane of glass you could consider using an etch bath solution such as Armour Products Etch Bath Dipping Solution.
Etching bath solutions require you to dip the entire project or piece of glass into the bath, so again you’ll want to ensure you use all the above personal safety protective equipment as listed above.
The thing I enjoy about etching bath solutions is the ability to use acrylic or oil paints to place a design onto the glass that then creates a negative version once you peel the paint off after being in the etching solution. You can even use sticker decals or vinyl patterns cut with your vinyl cutting machine to do more detailed designs or repeat the same design multiple times with accuracy. Armour Products sell a great “Over’N’Over” stencil material that is great for creating motifs.
Final Words on Chemicals That Etch Glass
I wouldn’t bother trying to get creative when it comes to glass etching solutions. Your best option is to use the easily purchased glass etching creams on the market and using the proper safety precautions. You’ll get a better, long-lasting, easier-to-apply result that doesn’t have you creating some sort of chemistry lab in your home.