Fused Glass Instructions

How to do Fused Glass

You should have already prepared your kiln and kiln shelf with kiln wash and run your kiln at least once without anything inside. This will allow your bricks and elements to fire and burn off any residue. Be sure to vacuum the inside of your kiln.

All set? Let's begin the fused glass instructions. The first piece can be a little intimidating. But, take the bull by the horns and let's get cracking. Try the following procedure for a simple beginner piece.

Supplies needed:

Before you begin, be sure you have prepared all your items. Be sure you have a prepared kiln and kiln shelf. To read more on preparing the kiln for firing, read the page on preparing your kiln .

Begin the fused glass instructions by cutting some glass. Glass can be cut into squares, or stack different designs and shapes. Try designing a simple design or pattern. Make a small piece for the first project.

To cut your glass, first dip your cutter in some cutting oil. An old film canister filled with odorless turpenoid or turpentine works fine. This step is important in keeping your cutting blade sharp and running smoothly.

Run the cutter across your glass to make a cut. Use firm pressure. A clear even scratchy sound will be heard as the blade moves across the glass. Make only one straight cut; don't go back over the line.

Breaking the glass can be done by using a pair of breaking pliers or use your hands. When using the breaking pliers, place one hand over the cutter and the glass to prevent any flying glass from shoot up towards the face.

Clean all your pieces to remove any oil and particles. This is an essential part of the fused glass instructions. Fingerprints can leave marks on your finished piece that will show up after firing the item.

Use either kiln wash, fiber paper or shelf paper to prepare your kiln shelf. Grab you pieces by the edge so that you don't put any fingerprints on your piece. Arrange these pieces in your desired design on the shelf. Placing the base piece or largest piece of glass on the shelf first, then adding any decoration or other pieces.

Use the thinned Elmer’s glue to hold the pieces in place. Don’t try to glue pieces in awkward positions, because the glue will burn off before the pieces start to fuse, and the pieces might shift and fall out of place.

Once the pieces are all arranged, close the lid. Make sure that the peep hole plug is in place and turn on the kiln. If the kiln has a kiln sitter, program it according to the instructions. If you have a pyrometer, you will need to watch the kiln and glass carefully.

The target temperature for a full fuse is approximately 1450 degrees Fahrenheit. You can heat your kiln at about 900 degrees Fahrenheit per hour to 1000 degrees Fahrenheit. If you are using a side fired kiln then slow the heating to about 600 degrees Fahrenheit per hour. Then increase the setting to high, because you can fire as fast as your kiln can go up to 1450 degrees Fahrenheit. This is if you want the piece fully fused. If you want to only tack fuse the piece, you should only bring it up to about 1350 degrees Fahrenheit.

You want to get past the 1000 degrees Fahrenheit to 1300 degrees Fahrenheit range. This range is where your glass can devitrify.

What is devitrifying? This is when your glass becomes crystalline and brittle. Your glass will have ugly white stuff on the surface of the glass. You can hold your piece at about 1175 degrees to help relax the glass and reduce the amount of bubbles that can be between layers. Now back to the fused glass instructions.

The first time the kiln is fired, it will need to be constantly observed to see what is happening with the temperature and the glass inside. Some pyrometers are not set correctly, and don't always give adequate readings, so observe the pyrometer and glass to see if the readings are correct. Set your timer and check the piece every 15 minutes to see what is happening. Never leave an unattended kiln.

Once you reach 1350 degrees Fahrenheit or 1450 degrees Fahrenheit, depending if you are wanting a tack fuse or a full fuse, hold the kiln at that temperature. This can be done by just turning the knob down a knob or two. Every kiln is different, so you will need to adjust accordingly.

By removing the peep hole, you can observe the glass. Always wear protective glasses when looking inside the kiln. Replace the peep hole plug and wait for a few minutes before checking it again. This is where the timer comes in handy!

Once your surface is flat and the sides have rounded, your glass should be fully fused within 20 to 40 minutes. Remember each kiln is different, so watch your piece and make notes of your process. Don’t allow it to remain at this temperature for to long, or you might lose the shape of your piece.

Once your piece looks like you want, get ready to open the kiln. Now with gloves and safety glasses on, open the kiln door or top and allow the heat to escape from the kiln. Remember it is hot in there so be careful as the hot air escapes from the kiln.

This is called flash venting . This helps minimize the risk of devitrification and also speeds up the process. Care needs to be taken when you flash vent to ensure that safe procedures are followed. I have included this in the fused glass instructions, but it is only necessary when you want to make sure that the piece doesn't heat up any more. If you have achieved the desired look for you piece and you want to hold it at this look, then flash vent.

Allow the kiln to cool down to about 1000 degrees Fahrenheit, and hold it there for about 5-10 minutes to distribute the heat evenly. Now, close the lid and see how the temperature starts to rise up again. This is ok. When it drops back down to about 950 degrees, hold it there for about 30 minutes to anneal the piece.

At this point, if the kiln has thick fire bricks and seems to cool slowly, you can turn off the kiln, unplug it and allow it to cool to room temperature. If the kiln is a ceramic fiber kiln, you should cool it down at a rate of not faster than about 300 degrees per hour. Any piece that is up to eight inches across and anywhere from two to three layers thick, you should allow about six to eight hours of cool down time.

Always be sure to anneal your glass. If in doubt of the annealing process or times, do a shotgun annealing .

Never take your glass out of the kiln until it has reached room temperature. Doing so could cause thermal shock and the piece could break. Allow the air inside the kiln to reach below 100 degrees Fahrenheit before opening the lid.

An important part of these fused glass instructions...Always remember and make a habit of unplugging your kiln when not is use.

If your piece is small enough, you can turn it into a piece of jewelry. Now go show off your first piece!

I hope these fused glass instructions were not too complicate to follow and that you have achieved your first piece without any problems. Be sure to read the fused glass instructions a couple of times before attempting the first firing.

For a list of some of the common glass fusing problems that are not listed in the fused glass instructions, click here.

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