The moulding process

At the heart of the company is the foundry where bells are moulded and cast. It is interesting to note that the craft has hardly changed since the twelfth century, although a modern foundry uses contemporary tools and moulding materials. The technique is nevertheless very much the same to a large extent.

False bell

After the campanologist (bell expert) has calculated and drawn the bell on the computer, two stencils are made: one of the bell's interior profile and one of the exterior profile. The inside mould, or the bell's core, is then made, and on top of that, the outside mould. The latter is also known as the "false bell" because it is an exact replica of the bell to be cast. It consists of firm sand and a thin layer of wax on which inscriptions and ornamentation are marked. The next step is to coat the false bell with several layers of a heat-resistant substance. The entire form is then enclosed in a steel closed moulding which is filled up with moulding sand. After a drying period of several days, the outside mould is lifted away from the core and the false bell is removed. After its removal, any inscriptions marked positively on the false bell can be seen in a negative form on the inside surface of the outside mould. When thoroughly dry, the outside mould is replaced over the core to create a hollow space into which the liquid bronze can be cast.

For the casting of bells a mould of two parts is needed: one for the inner and one for the outer form of the bell.

The mould for the inner shape of the bell, so-called core, is built up.

For the outer shape of the bell, a model in sand and wax, called the false bell, is being made.

The false bel, modelled in sand.

A layre of wax is being applied.

Ornamentation and raised letter inscriptions being applied in wax.

The model for the bell to be cast has its final appearance.

A heat resistant coating is applied.

A metal structure has been placed around the bell, and the whole empty space will be filled with sand.

Once hardened, the outer mould, the so-called mantle, is lifted; destroying the false bell in the process.

The residues of the false bell being removed from the mantle.

The imprint of the false bell being checked in every detail.

The carefully dried mantle being put back over the core. Where the false bell had been is now a hollow space.