What do the first postage stamps, Fabergé eggs, and watch backs have in common? Rose engine lathes.
I love watching YouTube videos of lathes in action. There’s something incredibly satisfying about seeing a material spin at high speed and then, through the application of careful pressure, see a pattern or shape emerge. See, for example, this gorgeous wood-turned globe made out of coloured pencils. I also have fond memories of the Spirograph – that plastic tool that lets you draw beautiful spiralling patterns with minimal effort. But until recently I never thought about how the two could be combined.
The rose engine lathe is that combination. The actual mechanism is nothing like a Spirograph, but it produces very similar geometric patterns, and those patterns have found some rather high profile uses throughout history. The Penny Black, the very first adhesive postage stamp, contains a wavy pattern as an anti-counterfeiting measure:
Such decorations still appear on banknotes today. The wavy pattern was formed by a rose engine lathe (later replaced by a specialised geometric lathe); it cut the design into metal, and that was then transferred to the printing plates for the first stamp.
Fabergé eggs are famous for – among other things – the intricate interlaced patterns along their exterior:
That pattern, known as guilloché, was carved by a rose engine lathe and then enamelled over.
Many ornamental watch designs have a similar look. Once again, it’s the rose engine lathe:
So how exactly does this specialised ornamental lathe work? Well, through a series of cams the bit of the lathe that holds the material moves around in a pre-determined way: essentially, it wobbles back and forth or side to side enough to produce those distinctive rose patterns. Here are a couple of nice demonstrations: