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.