Upsetting and planing — shaping metal with hammer and anvil

A copper bowl begins as a flat, round plate. There is no waste, no welding and no joint — the entire shape is produced by the blacksmith moving the metal with the hammer. This is raising, the profession's oldest technique, and it requires both patience and precise handiwork. Where the lathe operator removes material and the caster pours it into a mould, the raiser preserves every gram and forces it into shape strike by strike.

With raising the plate is hammered over a form or in the air against a steel or wooden stake so the material is gradually drawn up into a hollow shape. You work in rings from outside in or inside out with tight overlapping blows. The metal stretches and thins where it is worked most and it is the smith's task to distribute the blows so the material thickness remains even. Meanwhile the work hardens the metal and the workpiece must be annealed repeatedly before it cracks.

The tool is just as important as the hand. The form is given by stakes (rounded steel heads on a handle clamped in a vise), dome-shaped anvils and wooden moulds, while different hammers give different marks. A driving hammer has a rounded head to stretch, a planing hammer a flat, polished head for the final smoothing. The hammer's surface imprints directly into the metal, so a scratched hammer gives a scratched item — the hammers are kept polished.

When the form is there, the piece is planished: it's lightly and systematically struck with a polished planishing hammer against a polished stake so the many small facets lie in a smooth, glittering pattern. Planishing makes the piece both prettier and stiffer because the last light strikes work-harden the surface slightly. A well-planished driven piece is known by its characteristic hammer pattern that catches the light—proof that it's handmade and not pressed in a machine.

Typical driven workpieces

• 01Bowls, pans and vessels in copper and brass
• 02Pitchers and teapots with driven spout and handle
• 03Church furniture: baptismal bowls, candlesticks, altar vessels
• 04Repair and reconstruction of older driven objects
• 05Sculptural and artisanal unique pieces

The most common errors

• 01For rare annealing → cracks in the edge or bottom
• 02Uneven slag distribution → skewed form and varying material thickness.
• 03Scratched hammer or stake → marks that cannot be polished away
• 04For hard blows → thinning and breakthrough locally

“A forged item is the sum of a thousand identical blows — not one strong one.”