glass artisan

What is Lampworking?

What is Lampworking?

Lampworking is:

  • an art
  • a form of glassworking
  • beautiful
  • a lot of Fun!
  • an expensive hobby
  • the process of using a flame torch to melt and mold glass

Lampworking is a process used in the forming of glass, typically smaller glass objects like beads, marbles, small sculptures, laboratory glassware, etc (usually less than 1-2 inches in diameter). You may be familiar with glassblowing, another glassforming technique that involves molten glass on a much larger scale (vases, vessels, plates, large sculptures).

Whereas glassblowing uses a very hot furnace (a glory hole) to heat the glass to white hot (around 2,400 F or 1320 C), lampworking uses a smaller torch to melt glass.

Brief History

Lampworking has started as early as the Egyptians over 5000 years ago. Many Egyptian decorative beads made in that era survive today, a testament to how durable and strong glass actually is! These original beads are thought to have been made in cone-shaped furnaces instead of the modern torch.

Lampworking became very popular in Murano, Italy in the 14th century. In the early days, glass was melted using the flame of an oil lamp (which is why it is called "lampworking"). They would blow air or use a bellows to direct flame from an oil lamp to heat pieces of glass. Lampworking in Italy was considered a very close guarded secret for about 400 years.

Eventually American artists began learning lampworking techniques, experimenting, and developing new styles. Today, most people use torches that burn propane and oxygen or portable MAPP gass.

Types of Glass

Soda-lime glass

  • the most common type of glass used in lampworking
  • "soft glass" because it melts at a lower temperature than boro
  • more brittle and prone to thermal shock than boro
  • has a much broader range of color than boro
  • can find unique colors including silver glass, metallics, opalinos, organics, webbing, etc
  • COE ~104

Borosilicate glass

  • "hard glass" because it requires higher temperatures (hotter, more expensive torches required) to melt than soft glass
  • more thermal stable, less resistant to thermal shock, less prone to cracking when cooled (therefore more forgiving to work with)
  • however, has a narrower working temperature
  • colors are more limited in range, but this is constantly expanding over time as boro gains popularity
  • some boro glass have very unique color properties not seen in soft glass (eg oxidizing or reducing glass)
  • more expensive than soft glass
  • COE ~33

(Other types of glass include Bullseye COE ~90, Spectrum COE ~96, Czech glass COE variable)

Beads, Marbles, Sculptures, and more...

When I say "lampworking," I usually refer to the process of making lampworked beads. However, lampworking is a versatile technique that can be used to make a variety of glass objects. Popular products include:

  • Glass beads for jewelry
  • Glass Marbles
  • Small glass sculptures and figurines
  • Hollow glass beads for storing small amounts of cremains, flower petals, dandelion seeds, small seed beads, sand, small shells, etc
  • Glass vessels with stopper, able to hold small amounts of liquid like perfume, holy water, etc

There are also a very large number of styles and techniques to be mastered in the art of lampworking. Examples of different techniques include:

  • Stringer application - for horizontal and vertical lines, scrollwork, surface decoration
  • Dots, plunged dots - for surface decoration, making flower petals, internal trapped bubbles
  • Raking - using a tool to manipulate and move surface glass
  • Encasing - covering a bead entirely in a layer of clear glass
  • Implosions - 3d flower, explosion, or vortex look inside clear glass, popular in marbles

Lampworking is a complex art, and one piece often requires mastery of many sets of skills.

Size Limitations

You can make many different types of glass objects using lampworking, but you are limited by size. Buying a larger and hotter torch can allow you to make larger glass objects, but there is an upper limit. You will never be able to make things as large as glass blowers with a furnace glory hole are able to (bowls, vases, paperweights, large sculptures).

On a Hothead torch, the maximum thickness is about 1 inch in diameter, assuming you have a digital kiln. Anything that big will need to be kiln annealed. A 1 inch marble is guaranteed to crack if cooled in a fiber blanket or vermiculite. Glass objects will be increasingly harder to melt on a Hothead as you approach the size limit. The hothead simply does not have enough heat to heat the glass completely through when it gets larger than about 1 inch diameter.

If you are interested in working larger, you must invest in a larger, hotter, and more expensive torch. You will also need to upgrade your fuel system to a propane and oxygen source. This comes with its own set of expenses (propane tank, fuel, propane regulator, fuel lines, check valves, flashback arrestors; oxygen tank and oxygen service if you want tanked oxygen, oxygen concentrator for an alternative, oxygen regulator, etc).

On this setup, you will be able to make glass objects up to about paperweight size <3 data-preserve-html-node="true" inches. I typically do not work so large. But if you decide to make large objects, understand that it will take longer to add glass and heat up to shape, so will require more and more patience the larger you go.

Additionally, larger objects must be carefully heated continuously. The parts of the object not directly in the flame will cool and be at risk of thermal shock if not evenly heated occasionally (insurance heat). For this reason, boro is typically favored for larger marbles and sculptures.

Larger sculptures can be created as long as no part of it exceeds 1-2 inches in diameter. However, legs or any long thin protruding parts are most at risk of thermal cracking and require insurance heating.

Lampworking is a very complex and intricate art, the mastery of which takes years of dedicated practice. However, it is very fun and rewarding, and soon you will have a beautiful collection of fine glass pieces of art!

What do you enjoy about lampworking? What techniques are you most interested in learning? Post links to your glass works of art below, I am interested in seeing everyone's work!

Additional Reading:

For more information on the Tools needed to begin lampworking, please continue on to my post "Lampworking Tools!"

For more information on the actual process of making a bead, please continue on to my post How to Make a Bead!

If you are interested in more chemistry and physics, look at "The Science of Glass!"