First, an aluminum pattern is made in order to serve as the model for the future bell.
Wax decorations are applied in the same manner as in the lost wax method on the false bell.
Layers of fine loam are then applied over the surface of the pattern.
The cope is then built up to a thickness sufficient to withstand the pour and to key into the sand for the completion of the false bell.
Once the cope is complete the mold is flipped over, exposing the underside of the pattern. The pattern is then washed with graphite and prepped for the construction of the core.
Once the core is made in sand it is removed. The underside of the pattern is then heated in order to melt the wax on the surface of the pattern and the aluminum bell drops out of the cope.
The surface of the cope is then prepped and cleaned.
Both core and cope are washed, closed together, and buried in the pit.
The furnace is lit and the metal melted to over 2000 degrees Fahrenheit
The ladle is preheated once the metal in the furnace reaches the correct temperature.
Once the metal is transferred into the ladle it is rabbled with a willow pole, which cleans and degasses the metal.
The metal is then poured into the mold, the cup fed into the casting, and left to cool.
Once cool the mold is dug up from the pit.
The core is destroyed exposing the inside of the bell.
The cope is then turned up and the bell falls out of the mold.
The bell is then cleaned of all loam.
The bell then undergoes polishing and cleaning.
The bell is then loaded up and ready for delivery.
Lost Wax Process
The core is built up with red brick and loam and washed with graphite.
The false bell sweep is then fit to the molding spindle.
Modeling loam is then built up on the core to create a loam pattern of the bell, called a false bell.
Once the false bell is dry, wax is spread over the false bell to create banding lines and a smooth surface. This is also when wax decorations and inscriptions are applied to the surface of the false bell.
Layers of loam are then applied to the surface of the false bell. This is the beginning shell of the cope.
Once the loam cope is dry, the entire mold is completed with steel rings and sand is back rammed over the loam to create a mother mold. The entire mold, core, false bell, wax, and cope is then heated in order to melt the wax and facilitate the removal of the cope from the false bell.
The false bell is no longer needed, having served it’s purpose to create an impression of the outer surface of the bell in the cope, and is so destroyed.
The cope is inspected and cleaned of any remaining wax or debris. All wax decorations that were applied to the surface of the false bell are now in relief and backwards.
The cope is finished by sleeking a graphite wash on over the entire surface. This allows the metal to peel well from the surface of the mold and not stick or burn into the loam.
The core is also cleaned, the top molding hole filled, and sleeked with graphite.
As workers prepare to close the two halves of the mold together, a hole is dug in the pit.
The molds are then closed together and buried in the pit. Preparations are made for the pour.
The furnace is lit and the metal comes to a temperature over 2000 degrees Fahrenheit.
Once the metal is at the proper temperature, the furnace is tilted and the metal is transferred to the pouring ladle. The metal is processed, degassed, and poured into the molds.
The casting is then back fed manually to allow the bell to cool slowly.
Once the casting is cool, the entire mold is dug up out of the pit.
The casting is removed by destroying the mold. The core is dug out first.
Once shaken out of the mold the bell undergoes cleaning and polishing.
The Bell is then prepared for delivery.
Finally, the bell is installed for all to enjoy and ring!
The core plate is slipped washed and fitted with the core sweep.
Rough sand is built up to the surface of the sweep.
The rough sand is finished in a finer loam, dried, and blacked with graphite.
Starter loam is applied to the cope flask in preparation for the strickle.
The strickle is fit into place via a bracket and tension screw.
Loam bricks are struck up into the cope flask with fresh loam.
Fresh loam is applied over the surface of the bricks. The surface of the cope comes into shape.
Very fine loam is swept up to finish the cope.
The cope is taken off the molding platform and blacked in preparation for stamping.
The cope is stamped and sleeked.
Careful alignment and a steady hand are necessary to keep everything straight.
Having dried sufficiently, the cope and core and clamped together.
The mold is then buried in the pit with a bed vent and core pipe.
Burying the mold allows the metal to cool very slowly, giving the metal a finer crystalline structure.
The furnace is lit and the metal is brought to over 2000 degrees F.
Ladles are also loamed and burned-in to preheat.
Once brought to the correct temperature, the metal is transferred into the ladle.
A full 1,200lb. bucket of bell metal
The metal is rabbled with willow as a degassing agent.
In the metal runs.
Once full, the cup is back fed into the head of the casting to allow the casting to cool sufficiently.
Occasional topping up is sometimes necessary.
Extra metal is poured off into ingots for remelting.
Once cool, the casting is shaken out of the mold.
The bell is the pulled off the baseplate.
The casting is then scrubbed and brushed to assess the surface finish.
Once cleaned, the castings are prepped for tuning. Please visit our tuning page to learn more about this process.