The Money Synthesizer consists of my Geometric Oscillator augmented with an indexing circuit. It produces intricate fine-line designs similar to the security patterns on paper currency around the world.
Specialized lathes have been in use for hundreds of years to make complex patterns that are unreproduceable without directly copying them (i.e. photography or digital means). This is the historical art of guilloche (ghee-o-shay’) or Engine Turning. Remember the old 1970’s toy called Spirograph? It operates on a similar principle, producing mathematical curves called epitrochoids via revolving circular gears around eachother while a stylus traces their motion. Other combinations of motion can be used, such as mounting the stylus to a rotating disc as it traverses a straight line. Watchmakers and jewelers have long used these techniques for ornamentation on their work. The famous Faberge eggs bear designs engraved by a similar technique
Inside these sophisticated engraving machines, there are numerous settings to be made among the gears that revolve to cut the pattern. One doesnt need many meshed revolving gears before it becomes possible to produce endless patterns that are practically impossible to replicate. Hence this technique was adopted very early by national governments to mint their paper currency, postage stamps, and other monetary certificates. The U.S. Treasury is rumored to maintain such a machine, known as a Geometric Lathe, containing ten interlocked pattern-generating discs. The settings of the discs would only be known to a select few, as this information must be guarded from the hands of counterfeiters… at least prior to the digital age we are in now.
I’m not interested in counterfeiting. I’ve wandered into this area simply to explore the beautiful, peculiar patterns that this technique produces. Since my system is electronic, it has on-screen (oscilloscope) ‘preview’ capability that allows facile tweaking of a pattern before it is committed to hard media. Another aspect of my system is that it can produce designs outside the scope of a mechanical system; the ‘gears’ in my system (Quadrature Wavetable Oscillators) are not constrained to mesh with one another, and instead can spin at arbitrary and irregular speeds while still moving a stylus. Consequently, the coherence and beauty of true Guilloche patterns takes some tweaking to achieve with the Money Synthesizer…
Here’s some “money-ish” output from the Money Synth:
Details: Technical pen on paper. Typical dimensions 1.5″ x 8″. (2007).