Originally designed specifically for fusing the bottom of bottles, my bottle bottom molds can also be used with sheet glass. This quick switch will expand the usefulness of your molds, as well as give you new options and projects. Let’s get started!
Fusing with Window glass
Materials needed:
Bottle Bottom Mold – in this tutorial, the Celtic Knot mold is used
1/8″ (3mm) window glass or 1/4″ (6mm) window glass
Kiln wash or Zyp
- Cut circles of glass. The Celtic Knot mold is exactly 4″ wide, so we will cut our circles smaller, to center the design. It is very important that the overall thickness of the glass is AT LEAST 1/4″ (6mm) it can be thicker, but not thinner.



2. Place window glass on prepared mold (tin sides in) and fire to a full fuse:



This project can now be finished as desired. Things to think about:
- Add hanging loops during the fusing process. This will eliminate the need to drill holes. You can also add more than one loop to easily make chimes.
- Use sheets of unrolled bottle glass to make the same design, but in a color. Again, no drilling if you add loops.
Trouble shooting – sometimes things are not as awesome as you’d like, so here are some things to watch out for.
Not enough glass – using less than 1/4″ (6mm) glass can result in little or no detail in the design. This can be resolved by using the correct thickness of glass. If you are still experiencing a lack of detail, you may need to adjust your firing schedule to a higher temperature. (all kilns fire differently)


Fusing with Window/Bottle Sheet Glass on Bottle Bottom Molds
Segment | Ramp | Temp | Hold |
1 | 350 F | 1275 F | 20 min |
2 | 350 F | 1550 F | 8 |
3 | 9999 | 1060 F | 60 |
4 | 150 | 750 | off |
Fusing with System 96 glass
Even if you are not a recycled glass enthusiast, my molds can bring a new zing to your glass practice. Let’s have a look
Materials needed:
Acorn & Oak Leaves Mold (kilnwashed or Zyp coated)
Light Amber Streaky
Dark amber transparent
Dark Green transparent coarse frit

- Place the dark amber over the mold and trace the shapes of the acorns with a marker. Cut out and place in mold.


2. Add the green frit to the leaf cavities

3. Cut two 3″ circles from the light amber streaky, place one streaky side down on the mold. Add the nichrome hanging loop and add the other circle amber side up. Full Fuse using schedule for System 96 on Bottle Bottom molds. Consider adding multiple loops to increase your design options.




Schedule for System 96 glass – full fuse on bottle bottom molds
segment | Ramp Rate | Temperature | Hold |
1 | 350 F | 1250 | 20 |
2 | 350 F | 1450 | 8 |
3 | 9999 | 950 | 60 |
4 | 150 F | 700 | off |
Fusing with Bullseye glass (90) on Bottle Bottom Molds
Here’s a quick tutorial using Bullseye glass on a bottle bottom mold as well. Let’s get started!
Materials needed:
Butterflyfish Mold (kilnwashed or Zyp coated)
Bullseye Deep Royal Blue Transparent Double Rolled Fusible 3mm

1. Cut 3″ circles


2. Add hanging loop, fire to full fuse using the Bullseye 90 Fusing Schedule for Bottle Bottoms


Fusing schedule for Bullseye (90) glass on Bottle Bottom Molds
Segment | Ramp Rate | Temperature | Hold time |
1 | 350 F | 1250 F | 15 |
2 | 350 F | 1475 F | 8 |
3 | 9999 | 900 F | 60 |
4 | 150 F | 700 F | off |
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Fusing with Bottle Bottom Molds
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