Cylinder blown sheet
Encyclopedia
Cylinder blown sheet is a type of hand-blown
window glass
. It is created with a similar process to broad sheet
, but larger cylinders are produced by swinging the cylinder in a trench. The glass is then allowed to cool before the cylinder is cut. The glass is then re-heated and flattened. The result is much larger panes and improved surface quality over broad sheet.
In this manufacturing process glass is blown into a cylindrical iron mould. The ends are cut off and a cut is made down the side of the cylinder. The cut cylinder is then placed in an oven where the cylinder unrolls into a flat glass sheet. William J. Blenko
used this method in the early 1900s to make stained glass. These imperfect panes have led to the misconception that glass is actually a high-viscosity fluid at room temperature, which is not the case.
Other methods of producing hand-blown window glass included broad sheet
, blown plate
, crown glass
and polished plate
. These methods of manufacture lasted at least until the end of the 19th Century. The early 20th Century marks the move away from hand-blown to machine manufactured glass such as rolled plate, machine drawn cylinder sheet
, the Fourcault process
of flat drawn sheet, single and twin ground polished plate and most common, float glass
.
Cylinder blown sheet glass was manufactured in the UK in the mid 19th Century. It had been manufactured in France and Germany (and imported to the UK) since the 18th Century.
Glassblowing
Glassblowing is a glassforming technique that involves inflating molten glass into a bubble, or parison, with the aid of a blowpipe, or blow tube...
window glass
Glass
Glass is an amorphous solid material. Glasses are typically brittle and optically transparent.The most familiar type of glass, used for centuries in windows and drinking vessels, is soda-lime glass, composed of about 75% silica plus Na2O, CaO, and several minor additives...
. It is created with a similar process to broad sheet
Broad sheet
Broad sheet is a type of hand-blown glass. It is made by blowing molten glass into an elongated balloon shape with a blowpipe. Then, while the glass is still hot, the ends are cut off and the resulting cylinder is split with shears and flattened on an iron plate. . The quality of broad sheet...
, but larger cylinders are produced by swinging the cylinder in a trench. The glass is then allowed to cool before the cylinder is cut. The glass is then re-heated and flattened. The result is much larger panes and improved surface quality over broad sheet.
In this manufacturing process glass is blown into a cylindrical iron mould. The ends are cut off and a cut is made down the side of the cylinder. The cut cylinder is then placed in an oven where the cylinder unrolls into a flat glass sheet. William J. Blenko
Blenko Glass Company
Blenko Glass Company, located in Milton, West Virginia, is known for its artistic hand-blown glass.-Early history:William J. Blenko was born in London, England in 1853. He worked at a glass factory in his youth. In 1893 he emigrated to Kokomo, Indiana, in the US, where he established the first...
used this method in the early 1900s to make stained glass. These imperfect panes have led to the misconception that glass is actually a high-viscosity fluid at room temperature, which is not the case.
Other methods of producing hand-blown window glass included broad sheet
Broad sheet
Broad sheet is a type of hand-blown glass. It is made by blowing molten glass into an elongated balloon shape with a blowpipe. Then, while the glass is still hot, the ends are cut off and the resulting cylinder is split with shears and flattened on an iron plate. . The quality of broad sheet...
, blown plate
Blown plate
Blown plate is one of many types of hand-blown glass. It is made from broad sheet glass by laboriously hand grinding and polishing both surfaces. Blown plate is of a sufficient quality and size for mirrors and coach glasses....
, crown glass
Crown glass (window)
Crown glass was an early type of window glass. In this process, glass was blown into a "crown" or hollow globe. This was then transferred from the blowpipe to a pontil and then flattened by reheating and spinning out the bowl-shaped piece of glass into a flat disk by centrifugal force, up to 5 or...
and polished plate
Polished plate
Polished plate is a type of hand-blown glass. It is produced by casting glass onto a table and then subsequently grinding and polishing the glass. This was originally done by hand, and then later by machine...
. These methods of manufacture lasted at least until the end of the 19th Century. The early 20th Century marks the move away from hand-blown to machine manufactured glass such as rolled plate, machine drawn cylinder sheet
Machine drawn cylinder sheet
Machine drawn cylinder sheet was the first mechanical method for "drawing" window glass. Cylinders of glass 40 feet high are drawn vertically from a circular tank. The glass is then annealed and cut into 7 to 10 foot cylinders. These are cut lengthways, reheated, and flattened.This process...
, the Fourcault process
Fourcault process
The Fourcault Process is a method of manufacturing flat glass. First developed in Belgium by Émile Fourcault during the early 1900s, the process was used globally. Fourcault is an example of a "vertical draw" process, in that the glass is drawn against gravity in an upward direction...
of flat drawn sheet, single and twin ground polished plate and most common, float glass
Float glass
Float glass is a sheet of glass made by floating molten glass on a bed of molten metal, typically tin, although lead and various low melting point alloys were used in the past. This method gives the sheet uniform thickness and very flat surfaces. Modern windows are made from float glass...
.
Cylinder blown sheet glass was manufactured in the UK in the mid 19th Century. It had been manufactured in France and Germany (and imported to the UK) since the 18th Century.