Introduction to Lampwork - Part Three
Published On: 11-12-2011 10:40am
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Category: All About Lampwork Glass
There are many techniques in lampworking that a glass artist may mention when talking about their beads, knowing what techniques have been used is benifical to understanding the lampworking process and the quality of the beads. This list is by no means comprihensive but will give you an insight to the more common techniques and how they should look.
Encasing - Sometimes called casing this technique is often done with clear glass over a decorated bead. A bead is made and then the lampworker adds a layer of clear glass to the bead in order to magnify the decoration. This however isn't limited to clear glass on decorated beads. Encasing is the compeate covering of any colour over another, it is not often a lampworker will cover an opaque colour with another opaque colour unless they are using a smaller internal bead to make a larger bead from a more expensive or rare colour. Encasing is also done with coloured transparent glass over opaque glass or another transparent glass to make a new colour that is not availible. Fuscha pink is a very difficult colour for the manufaturers to pull though can be achieve by encasing one colour over another.
One thing to remember about encasing is that it should not distort the internal colour or decoration (unless that was the intention of the artist) it should also not contain to many bubbles caused by trapped air when applying the glass. Large bubbles cause stress in the glass that isn't removed by annealing.
Gravity - The biggest technique in the lampworkers arsenal, gravity is use to hand shape beads and manipulate the glass without the use of tools. Gravity is the control of the glass when heat is applied to it, basic physics takes over where molten glass is concerned and it will shape downwards, tilting the mandrel and holding the bead in different directions will change the lowest point of the beads and gravity will pull the molten glass downwards.
Gravity shaping can be use to make all sorts of bead shapes and is used a lot in making sculptural beads. Gravity can also be used to pull different colours of glass applied to the bead to create a gravity swirl bead.
Layering - Similar to encasing in that it is the application of one glass on another however layering doesn't cover the entire bead. Layering is used to create stacks of colour on a bead, to make the colours that can only be achieved by certain combinations of colour in certain places on the bead (such as a central band) or to create reactions. A common reaction is turquioise and ivory, when layed the elements used to create the separate colours react and cause a third colour (a stippled brown) to form around the edges of the layered colour,
Marvering - Marvers come in all sorts of shapes and sizes, every studio usually has a flat marver which is used to keep bead ends in check, flatten areas on the bead for shape and for holding things that you want to add to a bead for decoration.
Marvers also come with cavities that a bead can be rolled in to achieve uniform shape these are often called bead rollers the shape is symetrical and hot glass is rolled in it so it takes on the shape of the cavity. This is a technique taken directly from glass blowing techniques but modernised and adapted for direct use in bead making.
Because of the rapid cooling of the glass when it comes into contact with a marver (or any other tool) chill markes are formed on the bead which present themselves as little circles almost like the rings inside a tree trunk these are removed by the lampworker after shaping by fire polishing the glass in the flame.
Mashing - Similar to marvering but done on both sides of the bead at the same time, A bead is shaped as normal and then mashed in a masher tool to create a flatter bead. These technique broadens the range of bead shapes a lampworker can make with one simple tool. There are of course many typed of masher, some are curved rather than flat to preserve some shape on the top and bottom of the bead. The use of the tool on the bead does create chill marks that have to be fire polished off by the lampworker.
Mixing - Mixing glass rods together creates another range of colours not acheived by larering or encasing. Two rods are melted and mixed together to form either a solid colour or an effective glass with multiple bands of colour. The mixed ball of glass is then pulled into a new cane to be used in a bead.
Pressed - Presses are a mixture between a marver and a mashing tool, pressed bead shapes aren't perfectly symetrical all the way around the bead so not possible with just a marver but a press features a top and bottom component that fit together to help mould the glass to the shape, resulting in uniform beads for sets and another dimension of bead shapes. While the top and the bottom must meet together correctly the cavities on each side of the bead can be different some presses come with extra recess' or relief decoration so one side of the bead has a different look to it from the other. Some are flat backed while the top is domed making the shape easier for use in designs such as bracelets or pendants. Pressed beads are prone to chill marks just like marvered and mashed beads.
Striking - Some glass behaves differently after it has been put to the flame, striking glass only takes on it's true colour after being shaped and cooled then flashed through the flame to warm it and promote the reaction. Heating the glass to near molten keeps or returns the glass to it's original state but the quick flashes of heat make the reaction possible.
Reducing - This technique is done by changing the way the flame behaves by reducing the flow of oxygen to the flame it changes how the glass behaves and brings the metal content of the glass to the surface of the bead, the higher the metal content the more of a metalic sheen the glass develops. Some glass has very little or no metallic content so does not reduce.
Raking - Raking a bead involves spot heating a point on the bead and using a tool or stringer to then drag the area of molten glass to move the colours or create an effect on the bead shape. A variation of raking is swirling where instead of dragging a srtinger is used to twist the heated area and create a swirl.
Read the other posts in this series.
Part One - Different types of glass
Part Two - Terminology
Next up we'll take a look at bead decoration.
Encasing - Sometimes called casing this technique is often done with clear glass over a decorated bead. A bead is made and then the lampworker adds a layer of clear glass to the bead in order to magnify the decoration. This however isn't limited to clear glass on decorated beads. Encasing is the compeate covering of any colour over another, it is not often a lampworker will cover an opaque colour with another opaque colour unless they are using a smaller internal bead to make a larger bead from a more expensive or rare colour. Encasing is also done with coloured transparent glass over opaque glass or another transparent glass to make a new colour that is not availible. Fuscha pink is a very difficult colour for the manufaturers to pull though can be achieve by encasing one colour over another.
One thing to remember about encasing is that it should not distort the internal colour or decoration (unless that was the intention of the artist) it should also not contain to many bubbles caused by trapped air when applying the glass. Large bubbles cause stress in the glass that isn't removed by annealing.
Gravity - The biggest technique in the lampworkers arsenal, gravity is use to hand shape beads and manipulate the glass without the use of tools. Gravity is the control of the glass when heat is applied to it, basic physics takes over where molten glass is concerned and it will shape downwards, tilting the mandrel and holding the bead in different directions will change the lowest point of the beads and gravity will pull the molten glass downwards.
Gravity shaping can be use to make all sorts of bead shapes and is used a lot in making sculptural beads. Gravity can also be used to pull different colours of glass applied to the bead to create a gravity swirl bead.
Layering - Similar to encasing in that it is the application of one glass on another however layering doesn't cover the entire bead. Layering is used to create stacks of colour on a bead, to make the colours that can only be achieved by certain combinations of colour in certain places on the bead (such as a central band) or to create reactions. A common reaction is turquioise and ivory, when layed the elements used to create the separate colours react and cause a third colour (a stippled brown) to form around the edges of the layered colour,
Marvering - Marvers come in all sorts of shapes and sizes, every studio usually has a flat marver which is used to keep bead ends in check, flatten areas on the bead for shape and for holding things that you want to add to a bead for decoration.
Marvers also come with cavities that a bead can be rolled in to achieve uniform shape these are often called bead rollers the shape is symetrical and hot glass is rolled in it so it takes on the shape of the cavity. This is a technique taken directly from glass blowing techniques but modernised and adapted for direct use in bead making.
Because of the rapid cooling of the glass when it comes into contact with a marver (or any other tool) chill markes are formed on the bead which present themselves as little circles almost like the rings inside a tree trunk these are removed by the lampworker after shaping by fire polishing the glass in the flame.
Mashing - Similar to marvering but done on both sides of the bead at the same time, A bead is shaped as normal and then mashed in a masher tool to create a flatter bead. These technique broadens the range of bead shapes a lampworker can make with one simple tool. There are of course many typed of masher, some are curved rather than flat to preserve some shape on the top and bottom of the bead. The use of the tool on the bead does create chill marks that have to be fire polished off by the lampworker.
Mixing - Mixing glass rods together creates another range of colours not acheived by larering or encasing. Two rods are melted and mixed together to form either a solid colour or an effective glass with multiple bands of colour. The mixed ball of glass is then pulled into a new cane to be used in a bead.
Pressed - Presses are a mixture between a marver and a mashing tool, pressed bead shapes aren't perfectly symetrical all the way around the bead so not possible with just a marver but a press features a top and bottom component that fit together to help mould the glass to the shape, resulting in uniform beads for sets and another dimension of bead shapes. While the top and the bottom must meet together correctly the cavities on each side of the bead can be different some presses come with extra recess' or relief decoration so one side of the bead has a different look to it from the other. Some are flat backed while the top is domed making the shape easier for use in designs such as bracelets or pendants. Pressed beads are prone to chill marks just like marvered and mashed beads.
Striking - Some glass behaves differently after it has been put to the flame, striking glass only takes on it's true colour after being shaped and cooled then flashed through the flame to warm it and promote the reaction. Heating the glass to near molten keeps or returns the glass to it's original state but the quick flashes of heat make the reaction possible.
Reducing - This technique is done by changing the way the flame behaves by reducing the flow of oxygen to the flame it changes how the glass behaves and brings the metal content of the glass to the surface of the bead, the higher the metal content the more of a metalic sheen the glass develops. Some glass has very little or no metallic content so does not reduce.
Raking - Raking a bead involves spot heating a point on the bead and using a tool or stringer to then drag the area of molten glass to move the colours or create an effect on the bead shape. A variation of raking is swirling where instead of dragging a srtinger is used to twist the heated area and create a swirl.
Read the other posts in this series.
Part One - Different types of glass
Part Two - Terminology
Next up we'll take a look at bead decoration.
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