Nobody Casts Bells Like This Anymore!

Since 1770, the Mabilon foundry in Saarburg has been casting church bells the same way. What you are watching in this episode is the final and most demanding stretch of a process that began over three months earlier — when the team first started building the molds by hand.
In this episode, we follow the critical work week leading up to the pour. The molds are stripped down, cleaned, graphite-coated, and reassembled with the kind of precision that leaves no room for error. The clapper suspension ring must be set at exactly the right point. The cope and core must align perfectly. Then all five molds are lowered into a gravel pit and buried under three days worth of compacted topsoil — because only the pressure of the earth above can hold the mold together when four thousand kilograms of bronze comes pouring in.
The metal itself is no simple matter either. Bell bronze is seventy-eight percent copper and twenty-two percent tin, with strict limits on any foreign material. It has to reach eleven hundred and fifty degrees before it is ready. The pour is always scheduled for a Friday, so the bells can cool undisturbed over the weekend. Any vibration during cooling can ruin everything.
Five days after the pour, the bells come out of the ground. Months of work come down to the moment the cope is knocked away — what the foundry calls the true birth of the bell.

Original source material:
Glockengiessen. Teil 2: Der Guß
Published by Alltagskulturen im Rheinland
© LVR-Institut für Landeskunde und Regionalgeschichte
CC BY 4.0