Analysis by British engineers of samples of natural and artificial rubber
taken from the PzKw 3 tanks discloses some interesting points which are worth
recording.
Two very similar articles, i.e. a vision forehead pad and a cupola pad of
a 1940 model of this tank proved to be very different when analyzed. The former
was made of natural rubber and was secured to the metal by the brass plating
process. The cupola pad, on the other hand, was made from synthetic rubber and
was attached to the metal by an adhesive paint. These samples confirm the
previous supposition that the Germans have not yet learned how to make an
efficient joint between synthetic rubber and metal.
The most interesting sample, however, was a section of a bogie wheel tire
from a PzKw 3 tank (probably 1942). This sample proved to be made of synthetic
rubber. This is said to be the first evidence received by the British authorities
of this material being used by the Germans for solid tires. It seems to show that
the Germans have made sufficient technical progress to overcome the heating
difficulties previously arising when synthetic rubber was used for this type of work.
The method of adhesion to the metal band was by means of an intermediate layer
of hard, probably natural rubber.