Fine-grained sandpaper works, but of course a fiberglass pen also works.
You have to be careful with both tools that the fine details on the surface (buttons on the cushion, for example) are not destroyed.
But just as a side thought: We are talking about a fighter plane which was used at a time when Heineke seat parachutes were used by the Fliegertruppe des Kaisers.
NO cushion on the seat of the model would therefore not necessarily be wrong.
Servus
Bertl
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