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Donna Marcus's "Steam" is a permanent public sculpture in Brisbane Square. In 2006, Brisbane artists were invited to submit work for the site, and Marcus's piece was selected to anchor the space with a permanent, large-scale installation for the public.

The artwork takes its form from the work of 1940s architect Buckminster Fuller: 15 steel geodesic spheres - the geometry that translates straight lines into curved surfaces - assembled from 7,000 custom-made "vegetable" steamers and over 800 bolted plates. The design concept ran on "random disbursement," carried right through to placement - scaled-down versions of the spheres were thrown across Brisbane Square, and wherever each landed became the final location for its full-size counterpart.

Construction is mostly aluminium, with engineered and certified galvanised steel internal structural members - built to carry the load and stand up to ongoing public interaction.

Everything Metal worked alongside local engineering firms across the fabrication programme for Steam. The volume of repeat parts set the scale of the job from the start - 7,000 custom steamers and over 800 curve-pressed plates, all fabricated to the same form and finish, all destined to sit visible in a public square.

The 7,000 steamers were fabricated to the artist's specification, each one produced to suit its position in the geodesic geometry. Curve pressing on the plates gave the spheres their continuous surface form - 800-plus plates pressed to consistent radius, ready for assembly.

Machine drilling carried the load on hole work. Around 725,000 holes were drilled across the parts package to take the bolted connections that hold each sphere together. With that many holes across that many parts, hole position and pattern accuracy were what allowed assembly to run without interference - every plate sitting where it needed to against the steamers around it.

Welding, assembly, and installation were coordinated closely with the artist, the contractors, and Brisbane City Council. The internal structural members - engineered and certified galvanised steel - were fabricated to carry the aluminium outer construction and meet the structural standards required for permanent public installation. From there, the spheres were assembled and installed across Brisbane Square in the locations the random-disbursement process had set.

15 geodesic spheres, 7,000 steamers, 800-plus plates, 725,000 holes - delivered alongside local engineering partners as part of Donna Marcus's "Steam" for Brisbane Square.