Whether setting a window pane, designing stained glass, or creating wine bottle art, cutting glass is a valuable skill. There are several methods for cutting glass, like wet saws and blowtorches. But is an angle grinder a practical option?
It’s possible to use an angle grinder to cut glass. However, the high speeds and intensity increase the risk of breakage/cracks and injury. Securing the glass, taping the cut line, and going slow will reduce bad outcomes. Be sure to use the correct disc attachment and safety measures beforehand.
Before cutting glass, there’s a lot to consider, especially with an angle grinder. Luckily, we cover everything you need to know in the article below. Read on for more information.
Can You Cut Glass with a Grinder?
It’s best to use a tool capable of cutting through glass without risking any edges falling off or the glass shattering. For example, a grinder is an abrasive piece of equipment designed to cut materials without worrying about clean cuts.
Using a grinder to cut glass is possible as long as you use the proper disc attachments. For example, you can attach discs to a grinder that are made for glass to ensure that you don’t accidentally shatter the glass you’re trying to cut.
We recommend this simple handheld DeWalt battery powered angle grinder (on Amazon) paired with these discs designed specifically for glass cutting (also on amazon) for the best results here.
What Type of Glass Should Not be Cut with a Grinder?
Not all glass is created equal. Some materials are more durable than others and can’t be cut or drilled. Unfortunately, cutting through tempered glass with a grinder or any other tool is impossible.
Tempered glass, often called safety glass, is heat-treated and engineered glass four to five times stronger than standard options. As a result, the material is incredibly durable and designed to break into tiny, granular pieces instead of sharp shards.
The glass won’t break easily if you decide to cut into it and will create web-like cracks if pierced.
How to Cut Glass With a Grinder
Although cutting glass with an angle grinder is possible, it can be challenging due to the high speeds and abrasiveness. Therefore, you’ll need to practice extreme caution and take proper safety measures before beginning. Here’s how.
Step 1: Take Safety Precautions!
The first step is to take suitable safety measures to avoid injuries. Glass can easily shatter and cause harm if you aren’t careful. Ensure you wear gloves, goggles, masks, and other safety equipment.
Depending on the project’s scope, you may also need another set of hands or clamps to secure the glass in place. Cutting glass bottles and jars will typically require another person or clamps.
Step 2: Use the Right Equipment
You’ll need to use the proper disc attachment for your angle grinder. You can find diamond-coated grinding discs at your local hardware store or online. Ensure you’re using a compatible disc for your grinder for the best results.
Step 3: Secure the Glass
As mentioned earlier, depending on the project, you may need to secure the glass. Clamps or another set of hands work well for glass bottles, but this can pose additional safety risks.
Alternatively, you can support the glass on a flat surface. The glass will almost always shatter if the surface isn’t flat. Be sure the glass is secure beforehand with a cushion or towel underneath to reduce the chances of breakage.
Step 4: Slowly Start Cutting
Before cutting the glass, you will want to place electrical tape around the area you want to cut. The tape will help you line up your cut and reduce the abrasiveness of the angle grinder.
Afterward, start slowly cutting the glass. Be as gentle as possible and go slow, as angle grinders rotate extremely fast. You may want to take frequent breaks or splash water on the glass to prevent the surface from overheating.
Finally, do NOT try to cut a single line throughout the surface of the glass. Instead, cut about 20% at a time.
For example, if you’re cutting a glass bottle, you will cut 20%, leaving 20%, and then cut another 20%. Repeat the process until you’re finished.
Step 5: Sand the Edges Smooth
Now that your glass is cut, you’ll want to sand the edges smoothly. Silicon carbide sandpaper is suitable for wet or dry sanding techniques. However, using some lubricant when sanding glass is generally recommended.
Safety Tips to Keep in Mind
Cutting through glass has a high risk of injury, regardless of your tool.
Therefore, practicing proper safety measures is essential to avoid accidental harm. Here are some tips to keep in mind before starting your next project.
Wear Safety Equipment!
Glass can easily shatter into sharp, jagged pieces when drilling or cutting it. So ensure you wear safety equipment, gloves, and goggles before starting. You should also wear a mask, as it’s possible to inhale glass dust.
Avoid the Edges
Avoid cutting near the edge of the glass to prevent shattering and breakage. It’s advised to maintain ¾ inches from the border.
If you cut too close to the border, you won’t have enough support, increasing the shattering chances.
Avoid High Temperatures
You’ll want to be conscious of the temperature to avoid breakage or injury. Glass heats up when it’s cut, which can cause safety hazards if you aren’t careful. Use water or lubricants to maintain the temperature.
Alternatively, you can place a wet cloth under the glass to support it and keep it cool. Be sure also to spray water over the glass when cutting.
Increase Cutting Speed Slowly
There is no need to rush when cutting through the glass. Going too fast can cause the glass to break and increase the likelihood of injury.
Instead, go slowly and create a scoring line beforehand, if possible, to reduce the risk of accidents.
Other Methods for Cutting Glass
Although an angle grinder can cut through glass, the high speeds and abrasiveness increase the risk of shattering. Thankfully, other glass-cutting methods reduce the risk of breakage and injury.
You can cut glass with a blowtorch, acetone and string, diamond attachments, laser, wet saw, and tile cutters.
The best method for cutting glass is to score the material with a glass cutter and then apply light pressure to break the glass cleanly. Practice the correct safety measure with this method and place your glass on a flat surface.
Dipping the tool in cutting oil or kerosene is also essential to ensure a smoother cut.