Sunday, August 03, 2014

Wooden Treasure....

The sea holds many mysteries. Sometimes it decides to share one.

On a beautiful summer day Jerry was walking along the beach with his granddaughter when he happened upon 2 large wooden planks. Taking a closer look he could see these were no ordinary pieces of wood. These were from the hull of a wooden sailing ship.

Each of the planks is three inches thick. One is seven feet long and weighs 200 lbs and the other is over 10 feet long weighing in at almost 250 lbs.. Each plank still holds the original treenails used to build the ship.

 A treenail or trunnel, is a wooden peg or pin used to fasten pieces of wood together, especially in wooden shipbuilding. It is an ancient technology. This method of firmly securing such a fastener in shipbuilding was to cut a parallel peg of a softer wood, and then expand its outer end with a wedge of much harder wood driven into it called a foxtail wedge. Increased water content causes wood to expand, so the treenails gripped the planks tighter as they absorbed water.

Along with several brass spikes, the planks have copper sheets attached by nails. These copper sheets protected against ship worms and prevented growth along the ships wooden hull. This process dates back to the 4th century BC where lead was used in place of copper. Pure copper was used into the 20th century. However it was mostly replaced starting in the 1830’s with the introduction of a cheaper and lighter alloy called Muntz Metal.

These planks most likely sailed the oceans during the 1800’s as part of the hull of a merchant ship. Although we cannot ascertain the exact ship they came from, knowing the possible history made these an exciting find.

It was decided that they should be saved. So Jerry and Chet carried the 200 lb planks back to Jerry’s truck so they could be brought back to the squad building. 

At this point preservation techniques must be implemented. Any porous object exposed to the ocean collects salt and once the item starts to dry out, the salt crystals expand causing cracking and destruction of the material. This salt must be removed by soaking the object in a fresh water bath. Joe and Chet devised a plan to build a soaking tub built from materials lying around the squad building. Using some ½ plywood and a roll of plastic sheeting they created a 4’ x 11’ desalination bath. The bath is filled with fresh water and will have water changes regularly.

The planks will remain a mystery as to which ship they came from. But they will provide a small peek into the past of a great shipbuilding industry.

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