This week’s video comes courtesy of PPG. It demonstrates modern
techniques of making large sheets of flat glass that has a smooth
surface – something that perplexed glassmakers for centuries.

The first advances in automating glass manufacturing were patented in 1848 by Henry Bessemer,
(of steel-making fame), who developed a steelmill-like, but very
expensive process to produce a continuous ribbon of flat glass force
under heat between rollers. Another old method formed large sheets of
plate glass by casting a large puddle on an iron surface. Both of these
processes required secondary polishing.

Then in the 1950s, Sir Alastair Pilkington
and Kenneth Bickerstaff created the first successful commercial
application for forming a continuous ribbon of glass using a molten tin
bath on which the molten glass flows unhindered under the influence of
gravity. Full scale profitable sales of float glass were first achieved
in 1960.