Oaktoberfest (Sort of…) and a Toast

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Gary with his hard-earned trophy.

A few years ago, one of our former conservators Elsa posted about the successful effort to disassemble the port gun carriage excavated from inside USS Monitor‘s gun turret. And last summer, Kate added a post about long-term efforts to stabilize the wooden internal components from the carriage.

One of my favorite pictures from the earlier posts shows former staff guru Gary hoisting an oak gun carriage side from the Wet Lab’s overhead crane for documentation and photography. Here it is in case you missed it:   Read more

Wooden Gun Carriage Sides

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Newly constructed stainless steel mesh anode waiting to be installed.
Newly constructed stainless steel mesh anode waiting to be installed.

Some of you may remember that in the fall we spent some time doing maintenance on the wooden gun carriage sides from the disassembled gun carriage. Last week while Will was away at the annual AIC conference, Mike and I changed the solutions in these tanks, installed an anode and wired the carriage sides so that the iron bolts still inside the wood would be protected by impressed current. This is the same method being used to protect the metal components on the still assembled gun carriage, which can be viewed via the wet lab web cam here.

Check back soon to see updates about ongoing work in the lab.   Read more

Lifting, Rotating, and Rolling with Care

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Conservation staff use a 5-ton auxiliary hoist with lifting cables to move a 10-foot long section of wrought iron propeller shaft weighing 1,900 pounds.  The shaft's surface is protected from the steel lifting cables by rubber, foam, and canvas.
Conservation staff use a 5-ton auxiliary hoist with lifting cables to move a 10-foot long section of wrought iron propeller shaft weighing 1,900 pounds. The shaft’s surface is protected from the steel lifting cables by rubber, foam, and canvas.

The act of moving USS Monitor artifacts during conservation or onto exhibit at The Mariners’ Museum often isn’t very simple.  Factors like an artifact’s size, weight, fragility, and material composition must be considered before any move occurs in order to avoid damaging these precious artifacts. Minimizing movement during treatment and exhibition is critical to the overall health and long-term survivability of fragile artifacts. Often times the Monitor Conservation team spends days or even weeks planning and prepping for a move that may take no more than a few seconds or minutes.  Better safe than sorry! 

We use a variety of gear and equipment including overhead cranes, lifting straps and cables, shackles, chain hoists, lifting platforms, come-a-longs, pneumatic tires, dollies, forklifts, and good old-fashioned sweat and elbow grease.  But sometimes even the best equipment and planning is no match for 140-years of exposure to a corrosive ocean environment.  As a result, many of these treasured artifacts from USS Monitor are too unstable after deconcretion and conservation to move out of the exhibit.   Read more

Wood and metal meet science

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It generally goes without saying that we have a lot of metal artifacts to treat here at the Monitor Center. The term ‘ironclad’ does not exactly lend itself to images of wood or rope, but our collection of organic objects is not insubstantial. Thursdays have been devoted to survey of the organic objects in the walk-in refrigerator for the last couple of months, with a few breaks for other activities. This week we were doing something a little different, but still organic related. Some of you may recall that awhile ago one of the gun carriages was dissembled. The wooden sides still need to have their long iron bolts removed, an activity we hope to undertake soon, but for now those beautiful oak pieces are living in tanks with water, a corrosion inhibitor, and a biocide. The corrosion inhibitor helps to keep the iron bolts from corroding away until we can remove them, and the biocide prevents new ecosystems from growing in the lab. In addition to the corrosion inhibitor we are also using galvanic protection to prevent the iron bolts from corroding. The bolts are hooked up to magnesium blocks with electrical wire. Magnesium is less “noble” than iron in a galvanic series, which means that when it is connected to iron, magnesium will corrode faster than if it were unconnected. The other side of this is that the iron will corrode more slowly than if it were unconnected. So the magnesium will corrode into nothingness and the iron stays reasonably intact. The catch is that you periodically have to put in new magnesium blocks, an item we sometimes have difficultly tracking down. If anyone out there knows of a good source for magnesium blocks, please leave a comment or drop us an email.

So, as some of you may have gathered, Thursday was spent changing the solutions in these tanks and wiring in new magnesium blocks. Be sure to check back to the blog soon as we are testing dry ice blasting as a cleaning method this week. Hopefully there will be excellent results to share around this time next week.   Read more