? Air bubbles
Rather than being a defect to be avoided, air bubbles can be encouraged and exploited for their unusual shape and appearance. This is accomplished by deliberately trapping the bubbles between layers of glass .
The basic concept behind encouraging air bubbles to form is the creation of air pockets between the layers of glass. This can be done by sandblasting, drilling, or arranging cut pieces to promote the forming of bubbles. The tendency of bubbles to form at the intersection of ridges of glass can also be used creatively.
Textured glass can also be used to promote the formation of bubbles. Two pieces of ribbed textured glass, for example, can be aligned perpendicularly to trap small bubbles at the intersection of the ridges.
Bubbles can also be created by using chemicals or solutions that generate gas that is then trapped within the layers of the fused glass. Ordinary baking soda is the most common substance used in this fashion.
To use baking soda to make bubbles, just mix about a teaspoon of baking soda with a cup of distilled water, then brush or spray the mixture onto the top of the glass. Allow to dry, then place a layer of clear glass on top of the layer with the baking soda solution. Heat, fuse, and anneal normally. Bubbles will form randomly in an uncontrolled pattern.
Using clear glass allows the bubbles to show up best. Varying the strength of the baking soda solution can lead to different results.
Courtesy of Warmglass.com
Wow, your a star Tanok!
I asked about this recently and was told it was witchcraft!
Thanks ever so much for sharing the big secret with us!
the secret's out! go forth and make bubbles gang :P ;D ;)
nah, I was following a link on here to warmglass and found it by accident!
(it's the same one i found before i made them ;) )
Sorry guys this is a truly terrible photo but the coaster has gone to a new home & this is the best there is. For all the photos's faults it shows how the bubbles form around the intersections of the layered glass. The orange (I know it looks red) is stringer & the bubbles formed around where the stringers cross.
No witch craft or baking soda required. :)
The advice to avoid bubbles is usually to make sure that the air has an escape route & you should slow down (within the usual parameters for the glass & kiln) the heating stages of the kiln cycle. So it figures that to create bubbles you need to make sure the air doesn't have an escape route & that you use a fast heating cycle (within the usual parameters etc..).
You need to be wary of bubbles being too large or having too many as they can affect the durability (is that the right word?) of the glass especially if you're going to use it for something practical.
Hope this helps
still love that design sarah ;D
Thanks Steph
I'm going to do more fusing - just need to find the time. I sort of miss this one as it was the first that really worked. But my friend loves it & its partner so that's all that matters. For some reason I seem to give all my fusings away :(
Very impressive and I have to disagree
that is witchcraft