How to Freeze and Fuse Glass
Freeze and Fuse is a Pate-de-Verre technique which is an extremely easy way to make 3D glass pieces. There is no need for high-temperature ceramic molds or the use of any glass binders. Molds can be made of any flexible material, such as silicone, plastic, etc.
Your 3D glass pieces fuse on a flat kiln shelf at about 1300 degrees F soaked for 20 minutes.
Safety Tip: Always wear a mask or respirator while handling powdered glass or mixing the paste to prevent inhaling small glass particles.
NOTE 1: You can freeze and fuse with any glass powder as long as it is all the same COE.
NOTE 2: An important factor to plan for when creating 3D Freeze and Fuse glass designs is the shrinkage of each piece which will be about 15% in all dimensions from the original size of your mold.
Steps to create a Freeze and Fuse Glass Project:
- Mix glass powder with water until the consistency of a thick milk shake.
- Place the slurry in a flexible plastic or rubber mold.
Tip 1: Wash your mold well the first time with soap and water to remove any oils. Always wash and dry the mold well so you do not leave water spots. This will make it easier for you to see thru your clear mold from underneath and determine if you have any air bubbles.
Recommendation: Clean out all glass powder before washing the mold or when you clean the mold any glass residue will form sediment in the drain and over time can cause blockage.
Tip 2: Never over-fill the mold. Simply fill until slurry is level with top mold. We suggest using a painter's palette knife placed on its side to run over the surface of the mold to level off any mold section that may be overfilled.
- Tap or vibrate the mold to make the glass powder settle to the bottom and to remove air bubbles. The Wetting Agent is an invaluable aid in filling rubber or plastic molds to help prevent bubbles.
Tip: When using a plastic mold, you can vibrate each one quickly to reduce the air bubbles by place the side of a hair dryer against the plastic.Make sure it is set on cold and blowing away from the mold for a minute or two. Of course you can always use the tip of your finger nail and tap each mold section from underneath to force the air bubbles to surface.
- Blot off the water on top to remove excess water. Use a paper towel or cloth that is clean and lint free and with minimum texture. You will probably have to do this more than once.
- Place the mold in the freezer on a level surface. The size of each mold section and your freezer will determine how long it takes to reach a full fuse.
Tip: If you want to build multiple pieces of the same item and then fire them in your kiln all together later, you can store the frozen items on a cookie sheet in the freezer but place a release down first like a piece of freezer paper so they will not stick to the cookie sheet. Don’t forget that the freezer dehydrates items left for long periods of time regardless if uncovered or air tight, so it not recommended that you store your Pate-de-Verre glass designs for long periods of time before firing.
- After the glass and water mixture is frozen, pop it out of the mold like an ice cube by holding the mold on the sides and gently pressing in the middle of each section of the mold.
Tip: We suggest that you place a piece of paper on a firm piece of cardboard. Lay the paper and card board on top of the mold and then flip it over. Gently press to remove each item. Do not raise the mold very high off the cardboard base so the item doesn't drop any distance. You do not want removal or dropping to destroy any detail.
- Place the glass shapes on a flat kiln shelf. We suggest tilting the cardboard onto the kiln shelf then sliding the paper onto the kiln shelf. Gently slide each item off the paper minimizing the handling of the frozen glass shape.
- Tip: Use a wide fine bristle paint brush to smooth out any areas on each frozen item. Use a narrow fine bristle paint brush to run around the edges to remove any lip that may have formed from over filling or sliding it into the kiln, around the base of the glass design. Brush any excess that is on the kiln shelf away from the piece so it can not bind to the item but take care not to contaminate any pieces close by, especially if they are a different color.
- Smaller Glass Shapes (like jewelry): Fire your kiln at about 1300 degrees F for 20 minutes.
Larger Glass Shapes: Use a slow ramped up the temperature of 40 degrees/hour starting at 1200 degrees.
Tip: After fusing, the glass has to be annealed just as you would any solid piece of comparable size.
Although this freezing and fusing method requires NO binder, you might sometimes want to use Ultrabind to make a sticky paste. This will allow you to paint designs on the inside of a mold or create more 3D details by piping glass paste through a syringe or pastry bag onto the surface of the glass before firing. Because glass powder fuses at relatively low temperatures the binder, like Ultrabind, burns out well at low temps.
After they are fused, pieces are solid glass and may be used as you would use any other piece of glass. You can make them into jewelry, pins or magnets, or tack fuse them to larger pieces such as plates, tiles, etc.