Homage to the Cube, 1988/1999
Casting the Cube, 2010
Oxyacetylene welding is a process that uses fuel gases and oxygen to weld and cut metals.
In oxyacetylene cutting, a cutting torch is used to heat metal to kindling temperature. A stream of oxygen is then trained on the metal, which burns and then flows out of the cut as an oxide slag.
In this case the feed-lines are being cut from the interior of the sculpture's central tower.