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The Sheffield cutlery industry has thrived for centuries and Sheffield still ranks today as the world capital of cutlery manufacturing. The techniques and processes have changed little over the years, although the amalgamation of small firms and the introduction of modern machinery have to some extent streamlined production. However, the final stages still rely heavily on the craftsmen's hand-finishing skills to produce the fine quality product for which Sheffield is famous.
There are up to 60 separate processes involved in producing a single piece of cutlery, so we have picked out the key steps here to give you a good idea of what's involved without overloading you with detail.
Spoons and forks are stamped out of rolled sheets of the required metal. You can see more about the metals used in the stainless steel, silver plated and sterling silver sections above. Different thicknesses of sheet metal are used to produce different qualities of the final product.
First the 'blank', the outline shape of the piece, is machine-pressed out of the sheet metal. The webbing left behind is later recycled into fresh sheet metal.
For spoons, the bowl area is then cross-rolled twice to flatten it out so that there is enough material to later stamp and form a bowl of the right shape with a pleasant, usable thickness.
Forks are pierced once or twice, depending on which metal they are made from, to form the prongs.
Next, the handle design is stamped into the metal using a top and bottom die and the spoon bowl is clipped to the right shape.
Then the bowl is stamped and formed to the correct angle at the neck of the handle. Fork prongs are also shaped to the correct angle and curve and lightly rolled to taper them.
Each piece is then edged against a grinding belt to remove any burrs and polished using a polishing compound.
If the item is to be silver plated, this is done next. Silver plated and sterling silver pieces then undergo a final polishing process using very soft polishing wheels.
Knives are usually made with separate handles and blades which are joined together in the final stages of production. These are known as hollow-handled knives and are usually preferred because of the lighter weight and better balance. However, stainless steel knives can be made with solid handles. These are known as Monobloc knives and the process is described briefly at the end of this section.
Knife blades are made from stainless steel bar which has a high carbon content, allowing the finished blade to take and keep a sharp cutting edge. First, the bar is heated and formed under a series of drop hammer operations and the blade is rolled to the correct length and thickness.
Then both ends are clipped to form the blade shape and the tang, which is cross stamped to provide a good key when it is later cemented into the handle.
Next, the blade is re-heated and cooled to temper it to the required hardness and all the surfaces and the cutting edge are ground.
Finally, the piece is rumbled, glazed and polished, ready for the handle.
The two halves of the knife handle are stamped separately out of sheet metal which is thinner than that used for spoons and forks.
The pattern is formed between dies and after clipping the waste away, the two halves are forged together in a furnace.
After pressure testing, the handle is edged, glazed and polished. If it is to be silver plated, this is done next. Finally, the blade and handle are joined together with an inert cement.
Monobloc knives are made in one piece from the same metal bar that is used for blades. They are forged under a powerful drop hammer in just two hits, called preform and coin. Then they are finished using the same processes as blades. Because they are less labour-intensive to make, they are usually cheaper than hollow-handled knives.
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