About Cutting Glass and Related Questions
- Theresa Wolf
- May 11, 2024
- 4 min read
Updated: May 19, 2024
Lately, I've had several questions about some aspects of glass cutting, which inspired me to write this post. Some questions may have been asked before, but there is always a learning opportunity for everyone.
Before you continue reading this article, read my older blog posts that refer to glass cutting, as it may answer some other questions.
For the sake of making this post relatable to beginners as well as experienced glass artists, I'm going to break it down to the basics, but please forgive me if I digress. I'll attempt to stick to the pertinent subject matter.
Question: Is a 10" wet saw going to make cutting certain glass items (vases, drinkware, large cups, bottles, etc.) easier, The bigger the blade, the better...?
Yes and no. Each size and type of saw has its potential benefits and challenges.
Factors that change when going to a 10" wet saw from a smaller one, include more power and like, more safety features, adjustability - the option to cut wider objects, laser guidance, and more efficiency. The cons are the learning curve, you need nerves of steel, and the potential for breakage is larger, to name a few.
In short, all glass is NOT created equal. If you will, look at different types of glass as siblings from the same parent. Some glass can be classified, while others are considered "special purpose glass"). These include wine bottles, dinnerware, drinkware, etc. Handblown glass is almost always classified as COE 96 - this goes for all the shards you purchase or collect from glass blowers - however, it's not always annealed, so use extreme caution when cutting.
COE (coefficient of expansion) indicates how certain particular glass formulations respond to the heating and cooling process, which comprises all methods of glass manufacturing. Fusible glass also includes COE 90, borosilicate glass, and certain types of sheet-rolled glass (Bullseye, Spectrum, Oceanside, and more). SAFETY GLASS refers to the three patterns in which glass breaks. This determines the volatility, and how it reacts when broken.

NOTE: Soda-lime glass, lead glass, and borosilicate glass are the three main categories of glass. They make up around 95 percent of the cullet glass used in the production process. The remaining 5 percent of glass is special-purpose glass.
Question: How do you ensure the edges of cut glass items are smooth "enough"?
There are various ways of smoothing the edges of cut or broken glass, including glass sanding pads, special stones, electric grinders, and more. It depends on the glass and what exactly needs to be smoothed.
Question: What is the "best" way to cut wine bottles into rings, or lengthwise?
The most efficient method is with a wet saw and a diamond blade, i.e. made to cut glass with the added use of water. A few factors that are essential for cutting glass, aside from water, are a stabilizing system, and appropriate safety measures/gear.
For cutting glass that is less than 1/8" thick, a handheld glass scoring tool, along with the recommended oil or other lubricant, and proper technique, can be used. If in doubt whether something is tempered or not, cover the glass with something, and tap the corner. Tempered glass will very often make a loud bang sound when it breaks. This is because of the "stress" within the glass when it's manufactured (the chemical properties include a mixture of silica, potassium chloride, and barium oxide).
Tempered glass will break into uniform, square cubic shards that can be used in several ways. Extreme caution and the appropriate tools should always be used when attempting to break it. Always cover these items in a sheet/blanket before hitting them with a hammer (you only need a small hammer to apply enough force to a corner of the door/window. If you are looking for glass for your next project, look around for glass vendors that are willing to donate broken glass, including home improvement stores.
NOTE: Tempered glass (that hasn't been annealed) should not be cut with a saw or glass nippers, as it shatters when broken). This includes tempered glass used to make shower doors, fire glass, car windows, and oven doors, to name a few.
As far as cutting thin plate glass and stained glass sheets, do research, and find the tools that'll work best for you. Several factors, including the type of grip, lubrication, and cutting head, contribute to successful cuts. There are several cutting systems for strips and shapes like Beetle Bits, Creators Plus, The Morton System, and more. Some have more complexities than others. Read the reviews, and look at what fellow artists recommend.
Question: Is a wet saw difficult to use, and which brand/s do you recommend?
Irrespective of the brand, it must be a "wet" saw. The water is essential during the cutting process as materials, including glass, ceramic tiles, and porcelain, get very hot when cut with a diamond blade. The cost of a 10" wet saw, diamond blade, and stand, will range from $500 up. Using a Dremel with a diamond blade/bit is not recommended for cutting items that cannot be stabilized on a platform, and water is always a must!
ART GLASS (see below) can be cut with a tile saw (provided it was annealed properly). This glass can vary from thin to very thick, so cutting these will require some skill.
That's it for now folks! Please feel free to add questions! I will provide more information to help clarify certain things related to cutting glass for use in mixed media art.
Til then happy cutting!
Theresa
Very helpful!