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Λοιπόν όποιος ψάχνει λέει βρίσκει... Ιδού σχετικά με το deck
Wooden deckThe colour of U-boat decks has been a puzzling subject for many modellers. The horizontal deckcasing was made of thin steel, over which wooden planking was applied. The primary reason for using wood was that a metal surface ices up much more quickly in freezing weather than wood. Teak was too expensive to be used, so cheap local wood was used in its place. This explains why the wooden decks on U-boats did not exhibit the silvery appearance of weathered teak.
The painting list for U-boats in "Anstriche und Tarnanstriche der deustschen Kriegsmarine" (Painting and Camouflage of the German Navy) by Dieter Jung, Arno Abendroth and Norbert Kelling (Bernard & Graefe Verlag, 1997) states that the wooden deck was treated with a black wood preservative (Teerfirnis Tf 99). A U-boat deck started out as jet black in colour then quickly became charcoal in colour. As it was exposed to the elements, the deck developed a brown tinge. The more the deck was subjected to weathering, the lighter and browner it became. On the surfaces that were frequently walked upon, the wood preservative would wear more heavily and reveal more of the natural wood beneath. The deck would also become bleached by saltwater and the sun, causing small patches of white to appear. If a U-boat had not been serviced for many months, green algae would start to grow on the deck. As this plantlife was slippery, and therefore hazardous to the sailors walking on deck, the algae would not have been allowed to accumulate. It would have been removed before any serious built up took place.
The watertight ready-use ammunition hatches and some of the square-shaped hatches on the deck were not wood but metal. These were usually painted black or dark grey to match the treated wood. In rarer cases the square-shaped hatches were painted the same colour as the conning tower. The extreme bow and stern sections were also not covered with wood; they were either painted the same colour as the conning tower and upper hull, or they were painted the same black or dark grey colour as was used upon the watertight hatches and the square-shaped hatches. These metal areas were prone to rusting, whereas the wooden areas obviously were not.
During the loading of supplies before a patrol, numerous boxes would be seen on deck. The careless manhandling of these would have scraped and scuffed the deck. Also, when U-boats were in harbour or in dry-dock, their decks would be prone to paint and oil spills.
It is very important to recognise that a U-boat deck changed colour as it became more weathered. U-boats lying side by side would often have decks displaying different colours. These colours varied due to the conditions a deck had been exposed to, and the time since it had been last coated with preservative. This makes it difficult for a modeller to determine what a deck looked like at a certain point in time. The modeller must judge how weathered the deck had become by trying to establish when the U-boat was last given a major overhaul. A large degree of guesswork is required in this exercise.
An interesting point raised by Jeff LaRue is whether the colour characteristics of the deck preservative changed over the course of the war. Another related question is whether preservatives produced by different companies varied in terms of both colour and consistency. Yet another consideration is whether, late in the war, the supply difficulties reduced the availability of specified preservatives, and lesser quality alternatives were used in their place. Being unable to answer these questions, I can only speculate as to the variations between the preservatives used upon U-boat decks. But if there were variances, might the differences in the colour of U-boat decks in colour photos be due not only to weathering but the type of preservative itself?
Another aspect to consider is that a wet U-boat deck looks much darker than a dry one. A B&W photo of a weathered deck that is wet would look uniform and very dark - close in fact to the appearance of a clean, recently maintained dry deck in a B&W photo. This may confuse someone into believing a U-boat''s deck had recently been scraped and coated with wood preservative, when it actually was a weathered deck that was merely wet.