Friday, January 14, 2011

Stern repairs

The repairs of the stern have also been placed on the original blog to make it a complete story of the way the repairs were performed.

Stern Renewal
After both sides were repaired with new wood and new frames inside it was decide to start with the stern.
During the first inspection the stern did not showed the actual condition where it was really in.
During the summer months and during the repairs of the aft side it showed that most of the inside wood of the stern was rotten away and not only on the corners where the sides do meet the stern.
Going over several web sides it shows that this is a common fact in most of the Storebro 34 built most likely due to the construction and the way water runs of the ship.

First all hardware was stripped of the stern the next step was to document all needed holes in the stern and positions of other removed hardware from which a drawing has been made.

During the removal of the aft cabin it was also noticed that the deck supports had been rotten away and it was decided also to replace these.
To prevent that the hull form would be jeopardized by removing the deck supports and the complete stern first new deck supports were made.
Pine was used and to get the same roundness of the aft deck as original the new deck supports were laminated from pine cut planks and glued together wile strapped from portside to starboard side over the original deck.
When the new deck support was finished the deck end old deck supports were removed.

When removing the stern in small sections and not to loose the hull form the new installed corner aft frames where connected with straps to the center aft frame to keep them in place.
Some minor wood repair had to be done to the 3 frames from the stern ad the point where they meet the deck.
After these repairs the new deck support was glued and screwed in place before the complete stern was removed.

The next step was after cleaning all the old wood and making sure it was dry to install first two layers of Okumee sheets of 4 mm and 6 mm thick to create a new base with the correct stern form for the mahogany planks to be placed on.

The okumee sheets were place over each other to cover joints between the different installed parts and to make the base as smooth as possible for the installation of the mahogany planks.
The two different sheets were 100 %  glued with epoxy glue to each other.

After sanding the fitting started of the 20 mm thick mahogany planks which do have a tongue and groove which is better than the original installed planks.
One should be careful not cutting the planks to short since the roundness of the stern does have an influence on the length of the plank
After the first fit and pre-drilling the planks for fastening with bronze screws planks were removed again.
All new planks have been glued with colored epoxy glue to the okumee plates.

Plugs were glued in and than starts the slow process of cleaning the wood from the xcess of epoxy although most had been removed during the installation of the planks.
One important part is to use a band sander and not a rotating sander since one always starts with course and the groves created by a course sander will not be easy to be removed when these are circles on the wood.
Therefore the choice was made to use a band type sander which needs to be moved in the length of the planks in this case horizontal.

First Sanding

After the sanding a thin layer of epoxy was placed over the wood to protect the wood against the nature of the coming winter.

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