Our FAQ list is generated by all the questions people have been asking me for years. Every show someone asks me one, or more, of the following:
Our hand blown glass is food safe, but only for cold foods. Hot foods will cause localized heat, and stress, which will cause the glass to break. It might not happen the first time, or second, but it will eventually happen. We will have to trust you to use your own judgment here. (lawyers may all shudder now) Does the food have to come right out of the fridge? No, room temperature is fine. Should it have come from the oven or microwave? No. Can you pour in boiling water to make hard boiled eggs? Never!
On the other hand our glass formula contains no lead, and is safe for salad!
FAQ 2: Can you melt any scrap glass?
Well...
To paraphrase Gertrude Stein, glass is not glass is not glass. The glass in your car window is different from the drinking glass you pour a soda into, and not only because of their shape. The chemical formula's vary for different end uses of any given glass, and different manufacturing processes. A glass formulated to fly through a modern bottle making machine, which can turn out thousands of bottles an hour, is substantially different from the soda lime glass that modern studio glass artists employ. Soda lime glass has a lower melting and fining temperature, as well as a longer working time. It remains plastic over a broader range of temperature giving the glassblower more time to shape the glass between reheating.
Because of the differing chemical formula's each glass has a different coefficient of expansion. Imagine sewing a cotton pocket onto a silk shirt, and then washing it, in hot water just for grins. Do you think they would shrink the same? Neither does glass. Those different formulas all shrink just little differently, slowly, sometime for years, before just the right amount of stress accumulates, and crack. The piece of glass breaks for no obvious reason.
So, no I can't melt just any scrap glass. It does make a fine additive to asphalt however so don't stop recycling to keep a local glassblower in raw materials.
FAQ 3: Does it take really good lungs?
No, average lungs will expand the glass if it is hot enough. Imagine a length of steel pipe, about 54 inches, with a solid mass of room temperature glass on the end, about the size of a cantaloupe. An air compressor wouldn't expand it a bit. But imagine the glass is hot enough to imitate bubblegum, and any good pair of lungs will do nicely. Of course ‘hot enough' is a highly relative term, see FAQ #9.
FAQ 3: What happens if you inhale?
Well I usually do inhale, just in between the exhaling parts. However when blowing glass, I still need to breathe, so it is quite fortunate that the glass is at the other end of 54 inches of cold steel. The glass literally freezes up! And there isn't enough air in the pipe to actually breathe, so I just use regular air.
Yes I know this answer is a little flip, but the question always makes me giggle!
FAQ 5: What kind of paint do you use?
I don't use paint. All of the color is glass, added as the piece is formed. When color is 'painted' onto the glass in it's cold state, it is more properly termed stain, or enamel. Both must be fired onto the glass to become permanent. These decorative methods have been in use since, approximately 1000 A.D. (see: A Thousand Years of Stained Glass , Catherine Brisac)
FAQ 6: How do you get the color into the glass?
OOOOOOOh, BIG question, lots of answers! The short answer, and almost universally correct answer is that color in glass is created by introducing metal oxides into the glass formula. This is a complex and expensive process, requiring specialized knowledge, training, and equipment.
More than you wanted to know? Keep an eye trained here, as this section will expand, time permitting.
FAQ 7: Do you ever get burned?
Nope, not me, never. Well not so much any more.
The glass rarely gets you. You know its hot, it's moving, it's a different color than normal, and you avoid touching it. But there are a number of metal tools at hand, and they are also hot, at least some of the time, and these give off fewer visual clues. The worst burn is usually on a glassblowers forearm where the jacks touch just after tooling the glass. Since this tool is in almost constant use during any blowing session the opportunities for this type of burn are legion.
The best way to avoid this burn is tool placement. My tools are arranged on the bench to my right, and there is a definite order to the placement. As I am blowing I pick up and replace each tool in a defined area, so that the next time I reach for it a quick glance, or no glance at all, is enough to yield the correct tool without burning myself . Blowing glass is a dance, and your partner is dangerous unless handled correctly.
Seriously, yes I have been burned, on occasion badly. When in any doubt, see a doctor.
FAQ 8: What is the glass made of?
Short answer: Chemicals.
Basicly there are three components to glass.
The silica oxide is the basic glass forming element. Soda lime is added to help lower the melting temperature, and alumina is added for durability. This is still the SHORT answer. It is much more complicated in real, blowing glass life. Various other chemicals will be added to this formula, all of which add their own properties, affect the other chemicals in proportion to amounts, chemical nature, temperature, time and atmosphere of melt.
FAQ 9: How hot do you get the glass?
That depends on what you're doing. In degees F:
Different glass formulas will have slightly different temperatures.