Fusing Beginner's Playground

Brief History of Fused Glass Art

According to some historians, there is archeological evidence of the Egyptians using fused glass to create beads and jewelry in 2000 BCE. It was the main technique used to create small glass object until the creation of the blowpipe in Aleppo sometime around 25 BCE to 45 AD. Until much more modern times, fused glass was overlooked by the artisans of the Medieval Ages, as well as the renaissance. It has only been since the 1960's in the United States that fused glass as a hobby, and even fine art form has reemerged. It has gotten so popular in today's glass crafting that glass manufacturers are coming out with glass made specifically for kiln work.

What do we at Stained Glass Express offer for you?

Here at Stained Glass Express, we know kilns are expensive to purchase, pricey to maintain, and they're BIG! While we do carry some kilns for purchase (CHAMPXL), our Glass Academy actually has space in four kilns for students and for purchase from the public. $18.00 per square foot fired, and an additional optional charge of $3.00 for Bullseye ThinFire Paper, for a smooth bottom for your project. We have kiln programs for 90 COE and 96 COE, as well as for whatever molds you are interested in using.

We also have many opportunities for someone to come in and try! We offer many Fun Night Out fusing classes, as well as our Creation Station, which features up to ten different crafts for all ages (Children should be supervised but all projects are appropriate for ages 5+).

What to think about when creating a fused glass project?

What is the Coefficient of Expansion (COE) of your glass? Will your pieces be compatible?

Glass with different COEs will not behave and will not safely fuse together. When making your project, please bear in mind that Bullseye Glass is made as 90 COE, while Oceanside (previously Spectrum) and Wissmach Fusible glass are made as 96 COE. There are even likely instances where Oceanside and Wissmach will not properly fuse to each other. For the longevity of your project, we would not recommend using different glass manufacturers together, even if the claimed COE is the same.

The Six Millimeter Rule

The 6 mm rule explains that glass heated to a full fuse will flow until it reaches a thickness of approximately 6 mm (¼˝). To maintain this thickness, we recommend using two layers of 3 mm glass for the base plate. This keeps the final thickness around 6 mm. Adding more layers will cause the plate to spread beyond its initial boundaries. Conversely, using only a single 3 mm (1/8˝) base layer will cause the edges to pull inward, forming sharp points along the perimeter. Below you'll see an image describing the above. Each piece started with the same starting area, and with the exception of the unfused piece, they are just about all 6mm thick.

It is often better to fuse your glass "low and slow."

If your glass heats up too quickly in the kiln, it is likely that air may be trapped between your top and bottom layers of glass, especially if frit or stringers were used in between. If you set up your kilns to raise in temperature slower, as well as allowing time to "soak" at about 1150-1250 °F for 45-60 minutes. This gives time for the air to escape before the edges of your project have closed and sealed. In our classroom, we refer to this as a "bubble squeeze." It is built into the majority of our kiln programs.

What is the correct kiln program to use for my project?

This is a difficult question to answer, as every kiln may heat up a little differently. When working in an unfamiliar kiln, see if you can either make samples before you fire your piece, or maybe the owner or previous owner of the kiln has some. Here are some sample fires from two of our kilns, Lily and Bertha.

This is what we at Stained Glass Express refer to as a tack fuse. The purpose of this type of fuse is to adhere without changing the shape and edges of the glass too much. As I said, all kilns are different, Lily's tack fuse ends up with much sharper edges then Bertha's piece ended up.

Needed Equipment for Fused Glass

Thankfully fused glass does not require very much equipment to get a start on creating your masterpiece.

Glass Cutter

When picking a glass cutter, you should pick the cutter that is the most comfortable to use for you. While there are differences between the differing models, your comfort is the most important for a solid cut

Cutting Head

A cutting head will be included the majority of the time when purchasing a glass cutter, and they do occasionally have to be replaced. You should think about the project that you would like to work on. We sell two styles of cutting heads, one that makes curved cuts much easier, and one that cuts straight better

Running Pliers

Running pliers are designed in such a way that pressure is applied evenly to both sides of your score line. Many are designed with a sight on the top side of the pliers to line up with your score line. Please remember to orient them properly, with the concave side on top of the glass; the side that was scored

Grozers

Grozers, sometimes referred to as breakers, are meant for cleaning up an edge if the cut did not come out cleanly. Typically they are designed with a flat tooth on top, and a curved tooth on the bottom. They are used by breaking little bits at a time until you have reached where your score should have been

A kiln
- You will need a kiln in order to fire your glass. Glass can be fired up to 1650°F. The two glass fusing kilns that we carry can both be run from a 120-volt outlet, so you have the ability to plug and play! Be aware that they do take a lot of power, so ensure that you have it plugged into an outlet with a 20 amp breaker. You could also swap them to run off of a 220-volt plug, like your oven or washing machine.
- A microwave kiln is a fun budget way to get into this hobby. Please ensure that you are using a spare microwave, as the glass may fume. They are not perfect, or very accurate, but it can be a fun way to start.
- Kilns are expensive and cumbersome. If you do not have to ability to house a kiln, do not worry. Here at Stained Glass Express, we have a number of kilns to fire your work! We do charge by the square foot of whatever size your firing paper is.

If you're trying to fit more in your kiln than the square footage can handle, you have the option of kiln furniture. These are typically "stilts" of varying heights, as well as additional shelves. With the use of kiln furniture, you can build a new "floor" over your first project for any additional work you wish to fire.

Needed Consumables for Fused Glass Art

A consumable is something that you use that will be used up at some point, whether slowly or quickly. For reference, a common household consumable is a battery. There are a few things that will get "used up" when making fused glass. With fusing, there are not too many parts that you will need to purchase.

Shelf paper or Thin Fire
- This is a paper to go between your work to be fired and the kiln to reduce prep time. Generally speaking, we only fire using paper at SGE. It does degrade with heat, turning into a powder, so as long as the surface has not been disturbed when removing your work, you can fire using it again.

Fiber paper
- Fiber paper generally thicker than shelf paper is. Its use case is often for making sure space stays. if you were to put a piece of fiber paper between two pieces of glass and then fired it, the space where the fiber paper is will remain a void.

Adhesive
- While not inherently necessary, if you are laying out your piece away from a kiln, some sort of adhesive to ensure your pieces didn't move on you in transit may be helpful. There are specific products for this application, that are not true glues, so that you may continue to rearrange your piece should you choose. You could choose to use a glue as well, if you choose that route, please ensure that you are using a super glue (cyanoacrylate) with no additives, as those may not burn off cleanly in the kiln. We often use aloe vera in our classroom, just ensure that you again purchase something without additives, as those may burn off and contaminate your glass.
- You can use either the applicator tip of the adhesive or a small brush to apply.

Kiln Schedule for 96 COE Fused Glass Art

Please keep in mind that every kiln is different, and if the outcome of your firing is not what you expected, you may need to experiment with the timings and temperatures a little bit.
The following schedules are the 96 COE schedules created by Oceanside. This is what we base our schedules off of.

When firing at Stained Glass Express, we will need to know what level of fused you want your glass. In level of temperature, it would be tack fuse, contour fuse, full fuse, and a slump.
- Tack fuse is when the glass is in the kiln just long enough for everything to stick together
- A contour fuse is utilized when you still want edges and layers to your project, but they will be much softer edges than a tack fuse
- A full fuse is for firing when your glass is meant to be flat, all of the layers melt into each
  - When full fusing, be aware of the 6mm rule, as this could cause issues with your work
- A slump is meant for fusing glass over a mold to create whatever shape the mold is

Fused Glass Books

Are you interested in a book of projects to use, or a chapter on the 6mm rule? There is a book for you!

Frequently Asked Questions

What types of glass can be fused together?
Only glass with the same Coefficient of Expansion (COE) should be fused together. Common systems include COE 90 and COE 96. Mixing incompatible glass can cause internal stress and eventual breakage.

What is COE and why does it matter?
COE (Coefficient of Expansion) measures how much glass expands and contracts with temperature changes. Matching COE ensures the glass cools evenly without cracking.

Is fused glass food safe?
Generally, yes, if the piece is fully fused, properly cleaned, and made with food-safe glass. However, textured or tack-fused surfaces may trap debris and are better suited for decorative use.

Can fused glass go in the dishwasher or microwave?
Many fused glass pieces are dishwasher safe, but hand washing is recommended to preserve longevity. Microwave use is usually safe for simple pieces without metallic inclusions, but rapid temperature changes should be avoided.

What is annealing and why is it important?
Annealing is the controlled cooling process that allows internal stresses to dissipate. Without proper annealing, fused glass may crack immediately or fail over time.

Why are there bubbles in some fused glass pieces?
Bubbles can form from trapped air between layers of glass. Some artists minimize them with techniques like bubble squeezing, while others intentionally incorporate them as a design element.

Can fused glass be cut or altered after firing?
Yes, fused glass can be cold-worked using grinding, drilling, or polishing techniques. It can also be re-fired for additional shaping or design adjustments.

Does fused glass fade over time?
No, the colors are part of the glass itself and will not fade like paints or dyes. Properly made fused glass can retain its appearance indefinitely.

How long does it take to make a fused glass piece?
While assembly may take a few hours, kiln firing and annealing cycles can take 12–24 hours or longer depending on the size and thickness of the piece.