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Retrieved with permission from "http://en.wikipedia.org/wiki/Glass_beadmaking"
Lampwork glass beads.
Beads are amongst the oldest human art and technology, dating back 30,000 years (Dubin, 1987). Glass beads have been dated back to at least Roman times. Perhaps the earliest glass-like beads were Egyptian faience beads, a form of clay bead with a self-forming vitreous coating.
The most common type of modern glass bead is the seed bead, a small type of bead typically less than 6mm, traditionally monochrome, and manufactured in very large quantities. Once upon a time, these beads were made by puntying up a gather of glass, blowing a bubble, attaching a second puntile and pulling molten glass in opposite directions, reportedly in lengths up to 200 feet long. The tube was then chopped, the resulting beads rolled in hot sand to round the edges, sieved into sizes, and, usually, strung onto hanks. Modern seed beads are extruded by machine and some, (Miyuki delicas) look like little tubes.
Pressed glass beads
Increasing in labor costs are pressed or molded beads. These were (and are) made in the Czech republic, in what was once called Bohemia. Thick rods (20cm?) are heated to molten and fed into a rube goldbergian contraption that stamps the glass, including a needle that pierces a hole. The beads again are rolled in hot sand to remove flashing and soften seam lines. By making canes (the glass rods fed into the machine) striped or otherwise patterned, the resulting beads can be more elaborately colored than seed beads. One `feed' of a hot rod might result in 10--20 beads, and a single operator can make thousands in a day.
Lampworked dichroic
glass bead showing thin film application
Furnace glass beads A third technique, the most labor
intensive, is traditionally called lampworking,
because once upon a time the beadmaker used an oil lamp to create lampwork
beads. Lampwork beads are made by using a torch to heat a rod of glass and
spinning the resulting thread around a metal rod covered in bead release. When
the base bead has been formed, other colors of glass can be added to the
surface to create many designs. After this initial stage of the beadmaking
process, the bead can be further fired in a kiln to make it more durable. Modern beadmakers use single or
duel fuel torches, so `flameworked' is replacing the older term. Unlike a metalworking
torch, or burner as some people in the trade prefer to call them, a
flameworking torch is usually "surface mix"; that is, the oxygen and
fuel (typically propane, though natural gas is also common) is mixed after it
comes out of the torch, resulting in a quieter tool and less dirty flame. Also
unlike metalworking, the torch is fixed, and the bead and glass move in the
flame. American torches are usually mounted at about a 45 degree angle, a
result of scientific glassblowing heritage; Japanese torches are recessed, and
have flames coming straight up, like a large bunson burner; Czech production
torches tend to be positioned nearly horizontally. Increasingly, dichroic
glass is being used to produce high-end art beads. Dichroic glass has a thin
film of metal fused to the surface of the glass, resulting in a surface that
has a metallic sheen that changes between two colors when viewed at different
angles. Beads can be pressed, or made with traditional lampworking techniques. Italian glass
blowing techniques such as latticinio and zanfirico are adapted here to
make beads. Furnace glass uses large decorated canes built up out of smaller
canes, encased in clear glass and then extruded to form the beads with liner
and twisting stripe patterns. No air is blown into the glass. These beads
require a large scale glass furnace and annealing kiln for manufacture. Lead crystal beads are machine cut
and polished. Their high lead content makes them sparkle more than other glass,
but also makes them inherently fragile. Most lampworkers use rods
of glass 7--8mm in diameter, though premade stringers come in 1, 2 and 3mm
sizes (depending on the brand), and some brands come in very thick diameters
(15mm or more.) Sheet glass can be cut with tools into strips, though they're
easier to manipulate if attached to a rod first. (Glass also comes in particles
of various sizes, but these are typically surface decorations in lampworked
beads.) Many manufacturers who once only sold their glass in sheet or very
thick rod now provide rods for lampworking use. Window glass can
actually be used, but usually isn't, because it's not formulated for
flameworking (it's shocky, that is, cracks and shatters in the flame) and there
is little in the way of color available. The most popular lampworking glass
comes from Italy and is currently made by the Effetre company. Before it was
sold, it was called Moretti, and some people still call it that. Confusing
matters is that a cousin started a rival company; their product is called
Vetrofond, and is very similar. Effetre is a soda-lime glass, and, again is the
type most commonly used by lampworkers. Perhaps the second most popular
soda-lime glass (in the USA) is made by Bullseye, which markets their product
as being particularly compatible (find/link/write article about glass
coe/compatibility). Spectrum, Uroboros make 96coe glasses. Japanese Satake,
Czech (Ornela) and even Indian (PIG) soda lime glasses are also known. New
firms seem to be springing up like weeds to serve the glass beadmaking market,
which in the USA has grown from "about 30" to 70,000 people (Kate
Drew Wilkerson, interview, Dale Smeltzer's internet-only glass talk radio) In addition to soda lime glass,
lampworkers can use lead glass. Lead glasses are distinguished by their
lower viscosity, heavier weight, and somewhat greater tolerance for coe
mismatches. Satake, Czech and German glasses (the latter being marketed
primarily to glassblowers) all come in lead versions. Finally, beadmakers can and do use borosilicate
glass, a very hard glass requiring greater heat. This is laboratory glass, such
as Pyrex. Sue Ellen Fowler is credited for developing many of the original
recipes for colored borosilicate glasses, which became the basis for the
Northstar company's first products. Donald Schneider (personal conversation,
late 1990s) recalls how years ago he had to make all of his own borosilicate
colors (he still makes a tin white.) Northstar, and new Glass Alchemy (started
by a former chemist at Northstar) now offer many colors, introducing several
new ones every year. At one time, soft (soda lime and lead) and hard (boro)
glasses had distinctly different looking palettes, but demand on the part of
soft-glass artists for the silver strike colors on the one hand, and the
development of the bright, cadmium based `crayon colors' in the boro line on
the other, has softened the distinctions between them considerably. In any case, the beadmaker starts
by dipping a mandrel,
or wire (stainless steel welding wire, cut into 9 or 12inch lengths is typical,
at least in the USA) into a clay based substance similar to kiln wash and
letting it dry. Some brands allow for drying in the flame. The flameworker then selects rods
of glass which she heats in the flame of her torch. The mandrel
must also be heated, or the glass will not stick. When both glass and mandrel
are sufficiently warm, the beadmaker starts rotating the mandrel (usually with
the non-dominant hand) while allowing the glass to wind upon it---sort of like
pulling out a strand of cotton candy, or wool batt while spinning. The usual beginner bead is a simple
donut shape. The
beadmaker can use a paddle, a small slab of graphite or brass to shape the
glass in different ways---long thin barrels, bicones, tabs, and so on. Czech
beadmakers, who can produce up to 1200 (identical) lampwound beads in 2--3
days, are particularly known for their use of jigs to help rapidly shape the
bead into the desired silhouette. Getting a good shape is quite often
the longest part of the process, though onlookers tend to be most impressed
with surface decoration. Some beadmakers rely solely upon heat and gravity to
shape their beads; most at least use a graphite paddle to coax the bead into
the shape they want. Other common tools for shaping beads are mashers,
tweezers, picks, and even the rod of glass itself. There are many ways to decorate a
bead. One is to draw with a stringer, or fiber (a small thread, usually 3mm or
less in diameter) of glass on the surface, making dots, lines, or combinations.
Dots are particularly versatile and can be piled on top of each other in many
intriguing ways. Additionally, a sharp pointed object---for example, a tungsten rake
(or pick) or stringer of glass can be dragged through the surface design to
make feathers, hearts or other designs. Another very old, traditional design
involves sagging one part of a striped bead by heating it more, or rubbing it
with the paddle to shift the design into waves. Glass can also be broken into very
small chunks (frit) or even finely ground powders (e.g. Thomspson enamels) in
which the bead can be rolled; it can also be decorated with metals---silver,
gold, copper, palladium, and platinum. These are typically applied as very fine
leaf, slightly thicker foil, as fine wire, as fine mesh, or even as a metallic
deposit (fuming.) Good quality glass beads, like any
warm or hot-glass item, are then annealed. Large or complex beads go into an
annealing kiln immediately; smaller ones may be allowed to cool slowly, as with
a fiber blanket or by being plunged into vermiculite, and then "batch
annealed" at a later time. Lead glass (for neon signs) and,
especially borosilicate is available in tubing, making true blown beads
possible. (Soda lime glass can be blown at the end of a metal tube, or, more
commonly wound on the mandrel to make a hollow bead, but the former is unusual
and the latter not a true mouth-blown technique.) In addition, beads can be
fused from sheet glass or using ground glass (e.g. African beads, such as the
famed Kiffa
beads, are made using ground glass.) Molded ground glass, if painted into
the mold, is called pate de verre, and the technique can be used to make beads,
though pendants
and cabochons
are more typical. Lampwork (and other) beads can be painted with glass paints. Beads can be sandblasted; they can
be faceted, using lapidary techniques. "Furnace glass" beads, more
elaborate versions of the old seed bead technique described above, are also
being made. Chevron beads are multi-layer beads once exclusively
made using hot-shop techniques to produce the original tubing; but now some
lampworkers make similar designs on their torches (using borosilicate,--Kevin
O'Grady, demonstration, 2004 Gathering) before lapping the ends to reveal the
various layered colors. It should be noted that as torches get bigger and more
powerful, the cross-over between lampworking and furnace glass continues to
increase. Lampworked beads (with the
exception of Asian and African beadmaking) have pretty much strictly been the
provenance of Italian, and, later, Bohemian lampworkers for the last four
hundred years or so who kept the techniques secret. Thirty or so years ago,
some American artists started experimenting with the form. Their early efforts,
by today's standards, were crude-not surprising when there was almost no
documentation, and none of the modern tools. However, they shared their
information, and some of them started small businesses developing tools, torches
and other equipment. The "stump shaper" a popular shaped paddle, is
named after Loren Stump, for example. This group eventually formed basis
for the Society of Glass Beadmakers, which recently changed its name to the
International Society of Glass Beadmakers. Techniques diffused through the
population, via early books such as Cindy Jenkins' You can make Glass Beads;
the SGB's annual conference and their online forum; and just generally the
philosophy of sharing ideas, tips and techniques. This philosophy continues to
permeate the glass beadmaking world today, resulting in a huge diversity of
approaches, styles and beads.
Dichroic Glass beads
Furnace
Glass
Lead
crystal
Types of glass used in Lampwork beads
Rod
versus Sheet
Soda lime
Lead
Borosilicate
Basic Technique for Lampworking
Preparing the mandrel
Heating rod and mandrel
Beginner
Bead
Shaping
the Bead
Decorating
the Bead
Annealing
Other methods for making glass beads
Additional
Techniques for Lampworked beads
Brief history of modern beadmaking