Your Glass

Your glass was made by skilled men in difficult and dangerous conditions in conical buildings and could be 300 years old or more. Until the 1830s and early 1840s the window glass industry was almost exclusively concerned with producing crown glass. This type of manufacture was gradually superseded, however, by the introduction of sheet glass made by the blown cylinder process. By the turn of the century mechanical-drawn cylinder process superseded the hand process further industrialisation brought us float glass.

The cone glasshouse shaped in such a way that it acted as a chimney to remove coal smoke and other gasses, making working conditions more bearable.

Crown Glass

Crown glass was made byblowing a bubble of molten glass, which wasthen spunon a pointed rodinto a circular disc or “crown”The outer portion beyond the central knob was cut into small panes.The introduction of excise duty on glass by weight at the middle of the 18th Century favoured this process which allowed the thinnest panes of glass to be produced, albeit of a very limited maximum size. It was quickly adopted by the builders of that time, thus influencing the appearance of buildings of the Georgian period.Although not made by hand, our reproduction crown units have the subtle distortion made by the unevenness inherent in this process.

In the 17th century the largest panes of glass would be approximately 15cm x 10cm (6 inches x 4 inches); in the 18th century this had increased to about 40cm x 25cm (16 inches x 10 inches).

This shows the process of crown glass production; from left to right workers are blowing and enlarging a glass bubble, then forming a bullseye, or “crown”, on the low table. When it gets to a certain size it is opened up at one end and transferred to a pontil and spun out into a to a large disk.

Cylinder Glass

Cylinder glass was made by swinging a freshly blown glass bubble so that it stretched. Both ends of the cylinder were then cut off to form a tube which was then split down one side from end to end and opened out to form a flat, square sheet.larger sheets of glass meant that Victorian builders were able to use fewer glazing bars.

Cylinder glass; tubes being swung to elongate in trench. Glass kept molten by being reheated at the furnace through holes.

Float glass process

Float glass process was developed by Pilkington in the late 1950’s. A ribbon of glass is “floated” at a high temperature over a bath of molten tin. This enabled manufacturers to produce a sheet glass of a fine quality with a mirror like reflection, without any wave or distortion.

Low E

A low emissivity coating of microscopic metal particles, mostly silver, is applied to the glass as part of the manufacturing process . This reflects the ultra violet rays back into the room and reduces the U value of the glass.

Slimlite can be produced with a satin and all Pilkington decorative finishes.