utorak, 14. svibnja 2013.

A short guide about rebuilding wooden ships

Kupinova's port bow during works
During the big project of rebuilding Kupinova in Marina Vinici, the crew who worked on the overhaul learned a lot about repairing old wooden ships - especially about replacing worn-out madijers which form the hull.

For a start, here's a little glossary of this profession's unique expressions:

Madijer - individual plank which forms outer hull of the ship
Kimenat - space between madijers
Stupar - skilled workman which fills kiments with ropes and stupa
Ponat - raw planks of different sizes from which madijers are cut out
Kolumba (Kobilica) - keel, the lowest part of the ship, massive row which connects and holds planking and the ribs of the ship - the backbone of the ship
Broke - one of many expressions for nails, those which hold madijers in their places in this example
Koper - finishing and the most resistant paint which is used to paint the lower part of the ship
Laptopirreplaceable tool in works under and around the ship - a box which holds tools and can serve as a chair

Works after removing worn-out brokas
Before the replacement of the old and worn-out madijers, it is first necessary to remove the old ones. Also, the nails, broke, have to be removed so they wouldn't stay in the wooden ribs and accelerate the process of rotting of the entire construction. After the removal of the nails, their holes have to be filled with special mass which will keep the integrity of the ribs and, therefore, of the entire ship.

After the preparations for new madijers, the space is measured, and with those measures workmen can look for a suitable ponat from which they will cut the madijer. Ponat must be of the suitable size and length, and free of worms, termites, holes, it mustn't be deeply damaged or have unsuitable lines inside. Special attention must be put to those lines going through the length of the wood. If they are badly placed, the piece of wood could break during further work. When, finally, the suitable piece is found, it is first being sketched by the measures and the then it is sawed to approximate size (notice - madijers are rarely shorter than 3 meters, so sawing of each piece requires team work of at least three people). When madijer is cut to its approximate size, it is then meticulously processed to its final and desired size.

None of the madijers is completely narrow and straight as it follows curved lines of the ship. Therefore, it is necessary to curve it - more or less, depending on its position in the hull. Curved form comes from heating - with the open flame or by cooking it. Cooking is performed by keeping the madijer in a long narrow tube filled with fresh water while under the tube a fire is kept - for at least half a day. After that kind of processing, madijer is ready for incurvation and it is placed on its designated place on the hull. It is left there until the next day so it would cool and form into desired shape in the process.

Preparations for new madijers
During one of many cookings
After getting the madijer in wanted form, it is nailed into place with nails made from zinc (they have to be made from zinc because they do not rust as fast as regular ones). After they are completely hammered into the wood, the nails have to be put even a little bit further so they would absolutely hold the madijer in its place. This is done using a small metal piece which is held on the head of the nail by one person and then the other person hammers onto the piece, putting the nail into the wood for additional 1-2 cm. This procedure has to be done on every nail (there are two nails for every rib, there is one rib every 20 centimeters, and Kupinova has 19 meters in total) and also very carefully so there would be no broken fingers or damaged madijers. When nails are completely hammered inside, small pits remain through the surface and they demand further and very detail processing.

Some of many many nails that needed to be processed

During hammering, zinc protection of the nails is damaged and it is necessary to renew it - especially on the head of the nail. The simplest way to do this is
galvanizing them with spray. After putting on new zinc with spray, it is left to dry before further work. Until you finish spraying each hole from bow to stern, those in the front are already completely dry so you can start with another assignment. That is filling the holes with base paint and after it has dried, each hole has to be completely filled with putty (once again - just when you finish with one work, you can go on the beginning of the ship an start with another).

Vedran is filling kiments with paint while sitting on laptop

Putty for this kind of job is prepared by mixing the appropriate powder with oil and base paint. After the putty has dried in each hole (that takes about a day) excess material has to be planished (with grinder and sand paper) so the surface would be completely smooth. When that is achieved, painting is next.

Painting of the underwater part of Kupinova is done in three parts: first, there is a layer of red base color which is followed by a layer of silver underwater primer. In the end, two layers of koper of pale red color are put on the entire surface of the underwater part of the ship.

Kiments partially filled with stupa
The part of work which is equally important as taking care of madijers is work around kiments - gaps between madijers. During placement of madijers, workmen are trying to put them in such a way that the space between them narrows toward the inner side. That space has to be filled with material so it would become watertight. This work is done by special workmen - stupars. Depending on the depth of the kimenat, they have to fill it woth couple of lines of rope which is - by the old rules of the craftsmanship - hammered in tight form using axes. When there is enough rope in individual kimenat, stupa is put over it. Stupa is a kind of greasier rope in thinner lines which hammered into place using small chisels.

Painting of koper on the hull
The last unfinished parts of the ship are those which were under the pillars which are holding the ship when it is outside of the sea. They are processed when the ship is lifted by a crane - just before the returning it to the sea.

Mostly finished Kupinova awaits return to the sea
As for now, Kupinova is acting good during sailing on daily excursions. Also, no larger leaks have been detected so it seems that all the hard work and investments in Marina Vinici really paid of.

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