Making beads is a very skilled undertaking. Knowledge of which colours work well together chemically and good hand co-ordination are important. The artist starts by using a metal rod called a mandrel which is used as the base around which the bead is formed. They will dip it in a release agent which can be clay-based to allow the bead to come off after annealing.
Then they will select the glass to be used, which is also in a rod form. Both the glass and the mandrel are gently heated in a fixed flame until the glass is pliable enough to wind around the mandrel. This is done by rotating the mandrel in one hand whilst offering up the glass with the other. Many layers can be added, and techniques applied to incorporate bubbles or indents. Usually to finish, a layer of clear glass will be added to the bead which has the effect of magnifying to give depth.
The beads can be shaped by gravity or by using tools, paddles or presses. Once the artist is happy with the finished result, the mandrel is placed into a kiln where the temperature is raised to a specific heat for the type of glass to allow it to reach its stress relief point. It is not until the artist opens the kiln after cooling that they can see if the colours and design they have used have been successful.
The beads are taken off the mandrel and thoroughly cleaned, removing all traces of the clay release agent inside the bead hole. Sometimes a lampwork artist will work on a bead after this process. This is called cold working and can include sandblasting, etching and grinding. The exposure to the open air cools the outside of the bead while the center is still left blazing hot.
This can result in the cracking of the bead, which creates stress on the glass due to the extreme temperature changes as the glass cools in air. The beadmaker can avoid this by cooling the beads in a kiln. The artist will place the beads in a heated kiln set at a high temperature to ensure all areas of the bead are being heated evenly. The kiln allows the beadmaker to regulate the temperature and perform this cooling process over a period of several hours, in which the heat is gradually and continuously reduced until it becomes standard room temperature.
This process is known as kiln annealing. As an alternative to kiln annealing, small glass beads can also be placed between layers of insulation to cool them down. Although not as effective as kiln annealing, this is a fairly successful cooling process which allows the glass beads to cool at an even rate, which typically prevents cracking. Using the wound bead technique, the lampwork artist would dip the mandrel into a release agent such as a clay based material, or man made material such as boron nitride to allow the bead to release from the mandrel after it is formed.
The beadmaker will then choose rods of glass to heat with the torch until both torch and glass are heated to the proper temperature. Lampworking is a type of glasswork where a torch or lamp is primarily used to melt the glass.
Once in a molten state, the glass is formed by blowing and shaping with tools and hand movement s. Maltese Cross The glass is wrapped around a thin metal rod a mandrel , which later becomes the hole th rough the bead. Many effects can be achieved through using various colors of glass and various techniques. Some of the beads used are mass produced and others are limited editions.
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