Explosive forming is a technique for manufacturing wall panels out of sheet metal. The technique can be applied to many different types of metal to produce a virtually unlimited range of shapes and sizes.

Conventional pressing requires two mould forms and a positioning system, butexplosive forming requires only one mould form, reducing one-time costs.Explosive forming uses the force of an explosion to shape the metal sheet. The sheetis placed on a mould which is then submerged in water in which explosive has beenplaced. The force of the explosion presses the metal sheet into the mould form.In the 1950s explosive forming was mainly used in the aviation industry. Bythe1980s the technique had almost completed disappeared, but in 1995 TNO, the Dutch research establishment, carried out research into ways of using explosiveforming to satisfy the requirements of the day. The research revealed that explosiveforming was eminently suitable for the production of modern facades of high archi-tectural quality. Since there were no longer any suppliers of explosive forming ser-vices TNO set up a supplier itself, Exploform B.V.Two products suitable for architectural use are relief panels for flat elevations andcorner pieces for curved elevations.

Relief panelsRelief panels are flat sheets incorporating a motif. The motif can have any form required and can be different for each sheet. Although a different mould is requiredfor each motif, the moulds are relatively cheap.One example of the use of relief panels is for the frontage of the theatre/cinemacomplex in Alphen aan de Rijn, designed by Kraaijvanger Urbis architects. A wavepattern – given the name ’Desert Storm’ by the architect, Dirkjan Postel – wasmoulded into pre-painted aluminium sheets. The cost of the project was reduced bymoulding several sheets at the same time. Architect-designed buildings with curved metal elevations are costly. Each double-curved panel requires a mould to suit the particular panel. Exploform suggests twosteps to make a curved elevation affordable:
1. if possible make the elevation flat or single curved (i.e. bowed or twisted),so that no special mould is required
2. if possible make the double-curved parts of the elevation repeating, so that fewer expensive moulds are required.Neither of these steps should require any significant change to the design ofthe elevation.