Marcel Lorenz | Universtät Wien (original) (raw)

Papers by Marcel Lorenz

Experimentelle Archäologie in Europa, 2020

Summary – The hourglass-cast – possibly a prehistoric casting process? There are many variations ... more Summary – The hourglass-cast – possibly a prehistoric casting process? There are many variations of prehistoric casting processes for non-ferrous metals. At museums, lectures and in literature you can find techniques such as sand casting, lost-wax casting, open system casting, etc. Less frequently seen is the process of casting in a lost and closed mould. The German literature describes this casting process ethnographically and refers to this process as “Gelbguss” or “Hohlform mit Gussmetal” (FÖRSTER 1987, 132-138), “Guss in verlorener Form” or “Hohlform” (MENZEL 1968, 31-32) and “Guss im geschlossenen System” (ARMBRUSTER 1993, 290-291). We call it hourglass cast. The hourglass cast is similar to the lost wax technique. The desired artifact is created with beeswax and coated with lean clay. The mouth of the mould is designed in a funnel shape. Once the clay mould has dried, it is then baked to set the clay and to melt the beeswax, leaving behind the artifact's form. Unlike the lost wax technique, the obtained mould is not directly cast, instead the metals are placed at the funnel-shaped mouth of the mould. The mould is then coated and fully sealed in a further layer of treated clay. After drying and examining the mould, the process of melting the metals is performed in a suitable furnace. As soon as the melting of the metals has taken place the mould is turned upside down, like an hourglass, allowing the melted metals to fill the negative. Once it has cooled, the mould is smashed, freeing the freshly cast artifact. We have investigated this technique in an experimental archaeological manner. Referring to the ethnological source, the technique was imitated 14 times and confronted with archaeological issues. The conditions for performing a successful hourglass cast and the material requirements of the technique have been documented, while distinctions to known
casting processes have been acknowledged and discussed. We can support our initial hypothesis whether the hourglass cast is eligible for the creation of prehistoric metal items and answer it with a yes.

Experimentelle Archäologie in Europpa, 2018

Experimentelle Archäologie in Europa, 2020

Summary – The hourglass-cast – possibly a prehistoric casting process? There are many variations ... more Summary – The hourglass-cast – possibly a prehistoric casting process? There are many variations of prehistoric casting processes for non-ferrous metals. At museums, lectures and in literature you can find techniques such as sand casting, lost-wax casting, open system casting, etc. Less frequently seen is the process of casting in a lost and closed mould. The German literature describes this casting process ethnographically and refers to this process as “Gelbguss” or “Hohlform mit Gussmetal” (FÖRSTER 1987, 132-138), “Guss in verlorener Form” or “Hohlform” (MENZEL 1968, 31-32) and “Guss im geschlossenen System” (ARMBRUSTER 1993, 290-291). We call it hourglass cast. The hourglass cast is similar to the lost wax technique. The desired artifact is created with beeswax and coated with lean clay. The mouth of the mould is designed in a funnel shape. Once the clay mould has dried, it is then baked to set the clay and to melt the beeswax, leaving behind the artifact's form. Unlike the lost wax technique, the obtained mould is not directly cast, instead the metals are placed at the funnel-shaped mouth of the mould. The mould is then coated and fully sealed in a further layer of treated clay. After drying and examining the mould, the process of melting the metals is performed in a suitable furnace. As soon as the melting of the metals has taken place the mould is turned upside down, like an hourglass, allowing the melted metals to fill the negative. Once it has cooled, the mould is smashed, freeing the freshly cast artifact. We have investigated this technique in an experimental archaeological manner. Referring to the ethnological source, the technique was imitated 14 times and confronted with archaeological issues. The conditions for performing a successful hourglass cast and the material requirements of the technique have been documented, while distinctions to known
casting processes have been acknowledged and discussed. We can support our initial hypothesis whether the hourglass cast is eligible for the creation of prehistoric metal items and answer it with a yes.

Experimentelle Archäologie in Europpa, 2018