In 1963–4, Judd continued to explore the concept of open and closed space. A red floor box is a largely enclosed rectangular volume. However, a semi-circular channel cut into the upper surface is emphasised by an iron pipe inset into the trough. Judd tried to avoid positioning the channel in an obvious spot, commenting that I did a great deal of juggling to make it uncomposed. Another box, painted a vibrant chartreuse green, with a semi-circular yellow enamelled iron pipe inserted into the trough, demonstrates Judds early and unusual commitment to exploring the potential of colour in sculpture.
Although Judd continued to make handmade objects, he also began to have works constructed by fabricators. By using industrial materials and manufacturing processes, he wanted to eradicate evidence of the artists hand. To Susan Buckwalter 1964 introduces galvanised iron, a material he liked because it had no art historical context yet had a painterly quality in the way the light caught its surface pattern. Four metal boxes, hung at regular intervals on the wall are connected by a lacquered aluminium pipe inset into the top front edges. The spaces between the boxes have as much presence as the boxes themselves, and emphasise the depth from front to back. The alternation of open and enclosed volumetric spaces, and sequences of identical components, was to become a feature of Judds work.