Sculpting & Robotics: The role of CNC Robotics milling system in Kara Walker's 'Fons Americanus'

CNC Robotics
Milling System
KUKA + Hiteco
Kara Walker scultpture
Millimetre designers and makers

Background

Kara Walker’s 13.5-metre-tall statue, 'Fons Americanus', an epic working fountain, was installed in the Turbine Hall at Tate Modern.

millimetre worked closely with Kara and team to develop, fabricate, and install both the fountain and grotto elements.

Robotic System

Millimetre invested in a KUKA Quantec based milling system which was built by CNC Robotics Ltd. This set-up is highly flexible as the working envelope (larger than 1.5m3) enables large objects to be milled as a single piece.

The 'Fons Americanus piece

The piece explores the narratives of slavery and exploitation underpinning the British Empire, using the Victoria Memorial in front of Buckingham Palace as inspiration into subverting the concept of official public monuments.

The work was designed to have as small an environmental impact as possible. The substrate of the sculptures milled from laminated blocks of Portuguese steamed #cork, was devised as an innovative alternative to PU foam or polystyrene. When finished with, the carbon negative cork can be chipped and used as a soil improver.

Materials

The milling robot was utilized for #milling and #shaping the topographical cork. The final surface was formed from cementitious Jesmonite layered over the milled cork. The Jesmonite worked wet and cut back when semi-dry to produce the desired texture.

Capabilities

Millimetre's milling system is capable of wielding a variety of tools, such as carbide cutters from 3mm diameter up to 40mm diameter x 500mm long, plus a variety of rasps/burrs and sanding drums.

The accuracy of the setup is good at +/- 1mm, allowing it to be utilised even when working on smaller/detailed pieces.

Software/Programming

Millimetre design, model, and sculpt in Rhino, grasshopper, Solidworks and Freeform +. Autodesk Powermill Ultimate takes care of the programming of toolpaths. The milling system has been used over the last 5 years to produce varied and complex forms developed by millimetre, in a wide variety of materials from cork, modified timbers through to stubbornly hard English oak.

Other applications

Millimetre also use the robot/mill to produce:

· Large scale sculptural public furniture
· Shaped parts for high-end furniture in various hardwoods
· Complex jigs - to assist with assembly and for metal bending
· Formers – for lamination and for steam bending processes
· Patterns used to cast parts in Aluminium, Bronze and Iron
· Form-finding, model making and setting out