A great deal of ironwork was used when building VOC ships. For the reconstruction of 'De Delft' a forge was set up where, for example, rigging hooks in all types and sizes, rivets, fastenings, weapons, tools and nails are made.
Materials and tools
The first thing you need for ironwork is a forge: a plateau with a sunken trough in which an anthracite (coal) fire is kept alight. The bottom of the trough contains a hole through which ash and slag can be discharged. Low down in the trough there are also holes through which oxygen is added, so that the fire remains alight. These days the oxygen is supplied from an air compressor but previously bellows were used for this. Above the fire is a large hood for extracting the flue gases. A water trough is located next to the plateau.
Next to the plateau there is an anvil: a strong lump of iron with a flat surface and usually with a horn: a round tapered point around which iron can be hammered. The anvil is also often forged but can also be cast. The anvil is used for working the work piece: forging or welding.
A blacksmith uses hammers in all shapes and weights in order to forge hot iron into the required shape. A blacksmith also uses many different types of tongs for holding the hot iron. A blacksmith often forges the hammers and tongs he needs himself. Thick leather gloves are also necessary to protect your hands.
Until around 1900 blacksmiths used iron with a much lower carbon content and that still had residual slag, known as puddle iron, for their ironwork. Puddled iron is therefore easier to form than modern day steel, which is much stronger but which is also harder and less easy to form. Puddled iron becomes strong by heating it, forging it with hammers (which removes the slag) and by quenching it rapidly in water.
- A blacksmith starts by laying a coal fire and then lighting it. Depending on the size of the work piece to be made a large or a smaller fire will be laid in the centre of the coals. The fire is made hotter by adding more oxygen. The fire can be tempered by cooling down the coals around the heart of the fire using water. The slag that is generated by the fire can be discharged from the bottom: to do this, insert a poker from the side towards the underside of the fire and rake up the coals slightly.
- The blacksmith prepares the tools and the material required for forging. The blacksmith has already considered the work piece that has to be made; the iron required for it and the dimensions.
- The blacksmith lifts the material for the work piece using the tongs and places it in the centre of the forge. The material gradually becomes hotter, until it is red hot. It can now be worked.
- Once the material has reached the correct temperature it is removed using the tongs and held on the anvil. The material can then be hammered into the required shape using a suitable hammer. For example, the material can be hammered flat, as a result of which it becomes wider and longer. It can also be hammered into a round shape by hitting it around the horn.
- The material is usually reheated in the fire several times in order to be able to proceed with the next work operation.
- NB (1) During heating the material must not become too hot because it will then melt and the work piece will be lost. The best way for an apprentice blacksmith to learn is to first practice with various types and thicknesses of material, so as to discover when the material is hot enough for working but not too hot that it melts away. If the material appears to be not hot enough for working it can be put back into the forge to heat up further. Attention: if the material becomes too hot it will start to melt.
- NB (2) The water trough next to the forge is used for quenching and adequately annealing the ironwork when it is finished. The water is also used for tempering the fire as required and for dipping in the blacksmith’s heavy leather gloves to cool them down if the blacksmith has held the hot iron.
- NB (3) When forging large work pieces two or more blacksmiths work together. Once the material has reached the correct temperature they take turns to hit it so that the material can be worked as much as possible before it cools down too much.
- NB (4) When using steel instead of puddle iron some work pieces can no longer only be made from forging work. In that case a work piece is assembled from various pieces of steel that are welded together. The welded joint is then hammered in such a way that you can no longer see that there was a welded joint.
- NB (5) In the past a piece of ironwork was often fixed to the timber of a ship using forged nails. A forged nail is a tapered iron bar that can be hammered into a slot so that the work piece can be held in place. Nuts, bolts and studding are now mostly used. Ironwork can also be adapted to these by drilling a hole into the steel and tapping a thread in the hole.