“The sculptor is master of time; he can change his subjects forward or back”

– Irving Stone, The Agony and the Ecstasy

This may be true for art or the digital (just hit ctrl+z) but the quote certainly does not work for 3D printing. 3D printing is an agony and seldom leads to ecstasy, only relief when it actually produces a print in the right way. But when it works, 3D printing is a powerful tool that allows the intangible past that is carefully protected in museum showcases to be accessible, tangible and studied by people who are not trained archaeologists with special study permits. 3D printing can be an educational tool too: students can be introduced to material before they go on fieldwork, and modified 3D models of artefacts can be used in classes about ancient technology. It is even possible to print project branding and copies of museum replicas in bronze and chocolate!

 

For the exhibition ‘Tracing the conical cup’ we chose a single object as a focal point to demonstrate how archaeologists use innovative technology to do research into technology of the past: the iconic but unappealing and understudied Minoan conical cup. These cups from the Bronze Age were produced at various sites, often in bulk, and then distributed throughout the Aegean. In this way we could regard the conical cups as the disposable cups of the past, like our plastic cups of today. The Conical Cup Art installation of the exhibition is realised by the 3D printing of 42 cups in bright colours of PLA organic plastic filament to demonstrate this mass production and consumption. The installation is a nod to Pop Art, because it shifts between notions of popular use of everyday items in the past and unique high art (i.e. the conical cup as valuable object in a museum, or contemporary art). The hallmark of Pop Art was the recognisability of common utensils or items suddenly extracted from their usual context and elevated to art-pieces, like the soup cans transformed into art by Andy Warhol or, in our case, the conical cup exhibited in an artful way.

The installation for the exhibition required 42 3D printed conical cups and 9 manipulated 3D models of the bases of these cups that show traces of forming or modification. Fortunately, many 3D scans of reproduction conical cups created by Caroline had already been been made, and therefore only needed to be modified for printing. Bases are exactly the part that are the least visible, yet they contain a wealth of information about forming techniques.  All of these 3D models can be found here on the TPW Sketchfab page, and even downloaded to print yourself!

The cups and bases were printed with the Builder dual-feed (1), a machine that is able to print 2 kinds of filaments (printing materials) at once (even bronze and wood!). However, 3D printing is not as easy as it seems or should be: it is a machine, and machines most of the time don’t do what you expect them to: indeed up to 35% of the prints go wrong. The printer either starts printing spaghetti (7) or the object is pushed aside by the extruder (2, 4), after which printing continues but what it produces then could only be regarded as minimalistic incidental art (or rubbish). In other cases it prints only the interior filling and not the exterior surface (11, 12). Occasionally, when the filament becomes tangled, often only air is printed (5)! Objects with irregular top surfaces (read: all archaeological material) also form a problem for the printer. This is because the top surface cannot be printed to sufficient resolution, as this depends on the thickness of the printing layers: the more you increase the resolution (or layer height) the more time it takes to print, and time is precious (each cup print takes approx. 7 hours). If you try to save time by decreasing the resolution, then often you end up with an object that resembles a conch shell (8, 15). Finally, don’t forget that you have to be a technician as well, for the extruder often gets clogged (3) and the machinery needs to be opened up and cleaned, or parts need to be replaced (6).  

These failures, no matter how frustrating they can be, are still beautiful in their own way. So I sometimes see the Builder as a sculptor: it frequently creates its own unexpected artworks, but if the archaeologist doesn’t approve its creation, he or she just pushes the button again, as if nothing happened and we go back in time. The creation of a 3D print is therefore as agonising for the operating archaeologist as is the path of creation for most artists. Perhaps it is just as well that PLA 3D prints probably won’t survive as part of our modern archaeological record.