bakelite Kierspe plastic Polishing

Polishing machine

The polishing machine from the 1930s was used to polish products such as egg cups, coasters and ashtrays made out of bakelite. Today the Technikmuseum Schleiper Hammer puts it to use for presentations. It is driven through a transmission by an external electrical motor. The recording plays back the sound ensemble of the machine during the polishing of an already pressed egg cup out of bakelite. Because the bakelite egg cup still has uneven surfaces after the pressing process, they have to be polished even with the polishing machine.
The polisher turns on the machine and clamps the egg cup into the fixture, which is set into a turning motion by a crankshaft. The polisher uses the turning motion of the egg cup to remove the irregularities evenly using a file.
The sound scenery is defined by the sounds of the electric motor and the transmission machine. Further sounds are made by the clamping of the egg cup into the fixture and by the polishing.

Sound recordist: Konrad Gutkowski/Julian Blaschke
Photographer: Konrad Gutkowski/Julian Blaschke
Video recordist: Konrad Gutkowski/Julian Blaschke


18.3 MB
1 min 43 s
2 (Stereo)
Sample rate:
Bit rate:
Bit depth:
44.1 kHz
1411 kb/s
16 bit
84 dB

Recorded on April 9, 2015
Technikmuseum Schleiper Hammer
Kierspe, GERMANY
Creative Commons License