The thesis involves the construction of a replica of the Negovska helmet from the Podzemelj
burial ground. The helmet was found between 2016 - 2021, in one of 200 graves, dating
from the Early and Early Iron Age (5th-1st century BC) in the village of Podzemelj in Bela
Krajina. The helmet was made of bronze by a forging process and was ritually damaged
before burial. It was restored by cleaning of the soil and hardening with solutions and
Japanese paper. Unwanted holes and missing parts were filled in with Japanese paper and
epoxy resin.
The restored helmet was photographed using a hand-held 3D scanner. From the image, a
3D model was created in PLA material and smoothed to remove printing marks. This model
served as the basis for the silicone mould. This was made in two halves, with a plaster cap
supporting the silicone mould. The plaster model was cast into the mould, which was then
corrected to produce the original shape of the helmet, without ritual damage. Based on this
model, the silicone mould was again used to make the wax model. Wax was applied up to a
wall thickness of 4 mm. The wax casting system and air ducts were attached to the model. A
ceramic suspension was applied to the wax model, sanded in several layers. The prepared
shell was sintered at 1100 °C. A tin bronze melt with 10 % tin by weight was prepared in an
induction furnace. This was followed by casting. After solidification, the casting system was
removed, the casting was ground and polished to achieve the original appearance from that
time.
|