Centuries-Old Craft Meets Modern Tech at Grassmayr Foundry

In Innsbruck, Austria, the Grassmayr bell foundry—one of the last of its kind in Europe—continues to cast multi-ton church bells using techniques refined over four centuries. Yet the brothers Johannes and Peter Grassmayr have not shunned modernity. They now rely on 3D printing, laser scanning and simulation apps to design and produce bells that meet precise musical requirements.

While the core of bell making—hand-pouring molten bronze into clay molds—remains unchanged, modern tools have slashed the time needed for cleaning and polishing from 30% of production to just a tenth. A secret high-pressure sandblasting chamber speeds the finishing process. Still, designing and forming the molds for a large bell can take up to six months, and each cast risks failure if the extreme pressure of the liquid bronze destroys the mold.

The foundry, which once numbered among hundreds of European bell makers during the Renaissance, now faces a shrinking market. Fewer new churches are being built. Meanwhile, the cost of high-quality bronze—80% copper, 20% tin—has nearly tripled from €8 to €23 per kilogram in recent years, and rising energy and labour costs add further strain. To cope, the family has increasingly turned to restoring old bells with the same modern technologies, bringing back defective instruments from across 12 European countries.

The Pressures Shaping Europe's Last Bell Makers

Why Grassmayr Invested in Technology

For a craft that relies heavily on precision sound and durability, modern tools like 3D printing and computer simulation offer a way to reduce manual labour and error. By digitising the bell design, the foundry can calculate acoustics and strengthen molds to withstand up to 125 metric tons of pressure during casting. The brothers say innovation has accelerated a process that once felt more like art than science, helping them stay competitive when the number of bell orders from new churches is falling.

A Shrinking Market and Rising Costs

Johannes Grassmayr points to a dramatic rise in material prices—bronze has jumped from €8 to €23 per kilogram—as the single biggest financial pressure. Energy and labour costs have also climbed sharply since the pandemic. The foundry’s pivot to restoration work helps offset the decline in new bell commissions, but the reliance on high value-add, technology-assisted repairs highlights how traditional manufacturing must adapt when its core market contracts. The company’s survival, he suggests, now hinges as much on software as on molten metal.