How Lampworking Works

Cone-shaped furnaces similar to the ceramic chimineas that dot modern-day backyards and porches have been noted in many ancient cultures. According to some lampworking historians, these furnaces could have been used to make glass beads, and in fact, many Egyptian decorative beads from more than 5,000 years ago survive today because they were considered very valuable and were often buried with their owners. Though many things about lampworking and this ancient beadworking are similar, there are differences, too [source: Mickelsen]. Obviously, the fire used way back when was not the controllable source of heat of today's torches, whose flame can be turned up or down, or positioned toward one area of the glass. So whether or not these beads can officially be called lampwork is a matter of some debate.

What is not under much question is the fact that another type of furnace, known as the beehive furnace was in use from Japan to North Africa to Rome more than 2,000 years ago. Beads were used as a kind of money back then, so the thinking is that ways of making glass would have spread as quickly as a legal do-it-yourself mint would spread today.

Fast-forward 15 centuries, and you'll get to the beginning of "modern" day lampworking [source: Mickleson]. That's when artists wanted to "go green" in a medieval way -- they thought the techniques available took up too much energy to make such small end products, so they started to blow air from their mouths to direct the flame from an oil lamp to heat pieces of glass. The only problem with this do-it-yourself technique was the possibility of hyperventilation. But use of hand and foot bellows (like those used to fan the flames of a fireplace) soon put an end to that problem. Galileo is one artist known to have worked with these types of lampworking devices.

The next section will tell you about how today's lampworkers do their thing.

Not surprisingly, to melt glass in a modern fashion you need quite a few pieces of equipment in your workshop. Most can either be purchased at a hardware store, a welding supply store or a bead-making store. Here's a basic list:

And then there's the art of cooling and annealing the glass -- a very important step in lampworking. If you cool the glass too quickly, it will break due to thermal shock. When glass is heated, it expands. If the glass is heated or cooled too quickly, the different layers of the glass expand and contract at different rates, causing the glass to pull away from itself, and crack or break.

Bob Ponton, veteran glass blower and office worker for the American Scientific Glassblowers Society, explained thermal shock this way: Think about a heating a 1-inch (2.5-centimeter) ring of glass. Heat it too fast and the temperature of the outer quarter-inch (0.6 centimeters) will rise faster than the middle three-quarters, and that outer piece will expand and break away from the middle layer, cracking the glass.

He also explained that the glass used for lampworking is different than that used for, say, making soda bottles. "Put a pop bottle in the torch, it will look like it exploded because the glass expanded so quickly," he said. For lampworking glass, boron is added to the glass to change the expansion rate, or what's known scientifically as the coefficient of expansion.

Before he retired, Ponton made glass used for scientific purposes, and he used types of glass with maybe four or five different coefficients of expansion for that type of work. For the glass art he makes, Ponton said sticks with one type of glass, as do most glass artists. One thing that changes the coefficient of expansion is the chemicals added to give the glass color, so artists look for a glass that gives them a great color palette and then learn to work with the properties of that particular glass.

There are different tools to cool hot glass, including:

Read on for the equipment needed for the all important steps that come between the heating and cooling of the beads.

What about the actual bead making? You'll need plenty of tools for that, too, including:

And though the saying goes "safety first," we're discussing safety equipment last. You'll need:

How exactly does one use these tools and materials? Read on to the next section for a basic how-to.

Now for the fun part: how to actually make a lampwork bead. Here's a step-by-step guide to a very simple round bead with no embellishments or patterns:

Step 1: Heat the glass rod. To do this safely, you have to move the rod in and out of the flame so it heats slowly. Also twirl the rod so gravity plays on it equally, never letting the end droop too far.

Step 2: As the glass gets hot, start heating the coated mandrel as well. It should heat to an orange glow.

Step 3: As the glass becomes molten, start winding it around the heated mandrel. The glass and the mandrel should be in the flame as you do this.

Step 4: When the bead is the size you want, start pulling the glass rod away from the mandrel, continuing to rotate the mandrel the whole time. The glass will get thinner and thinner, and eventually break, a technique known as flame-cutting.

Step 5: Take the bead out of the center of the flame to its cooler edge. Continue rotating the glass. This process is called flame annealing -- it makes sure the glass' temperature doesn't drop too quickly, which can cause it to break.

Step 6: Further anneal the beads using either vermiculite or fiber blankets, and then eventually a kiln.

Step 7: Once the beads are room temperature, soak them in a bowl of water that is also room temperature. Then you can more easily remove the bead from the mandrel.

Step 8: Use a bead hole reamer to clean out the hole.

And voila! You have a bead!

So assuming you're not a super-quick study and you didn't pick up everything you wanted to know about lampworking from those eight steps, where else can you turn to learn more, maybe in person? Here are some places to check:

For more on lampworking, glass making and other related activities, blow on over to the next page.