A bubble squeeze is used to help eliminate bubbles from forming in your glass piece.
This process is used when fusing several pieces of glass together.
Bubbles are next to impossible to remove once they are trapped inside your glass.
Always check the layout of your piece and try to set it up so that air won’t get trapped between two pieces of glass.
You can also use frit, or small pieces of glass sandwiched around the edges of your glass.
These pieces will take longer to heat up and melt than the middle of your piece, allowing the air to escape.
Check on the internet to see what temperature your particular type of glass begins to move.
When figuring out what you want to make, factor in the size, color and design of your project.
Figuring out the bubble squeeze that works for your particular kiln is the key to this process.
What works for in one kiln may not be the perfect squeeze for another kiln.
Here are a couple of methods for doing a bubble squeeze:
Hold the Glass
Holding your glass at a set temperature will allow your glass to equalize out in temperature.
Slowly heat up your glass.
Once your glass has reached around 1000 degrees Fahrenheit, soak the piece for about 15 to 30 minutes.
This will allow the layers to relax and equalize in temperature.
Then increase the heating process at about 50 degrees Fahrenheit per hour.
Once you reach around 1220 degrees Fahrenheit, put in a half an hour soak.
This will allow time for the air between your pieces to escape before the edges seal and trap the bubbles in the glass.
If your arranged pieces are prone to trapping air, soak the item for two or three hours. Once you have finished your squeeze, continue firing your piece to either a tack fuse of full fuse.
Slowly ramping the temperature of the kiln can help obtain a squeeze.
Here is one way to figure out the best temperatures for your squeeze.
Check out the
Bullseye "know your kiln" test.
Keep an eye on your piece and see at what temperature the glass noticeably begins to slump.
With a bubble squeeze the pieces of glass are basically slumping against each other to push out the trapped air before the glass gets tacky.
The temperature the glass begins to slump at is the midpoint for the squeeze.
If the piece begins to slump at 1100 degrees Fahrenheit, then the squeeze should start at about 1000 degrees Fahrenheit.
Ramp up at between 50 degrees per hour to about 100 degrees per hour until it reaches around 1200 degrees Fahrenheit.
There should be no need to stop and soak the piece.
Return from this page to one of the following pages:
Bubble Squeeze to Glass Fusing Made Easy
Fusing and Slumping