After the documentation process is completed, the next stage in the conservation of the timbers is mechanically cleaning. Each timber is carefully inspected for gasket material, embedded rocks, shells, and corrosion from iron fasteners.

The WTC ship was built with iron fasteners, and iron corrodes in the presence of seawater. This corrosion forms patches of mineral encrustation at the site of the fasteners, and needs to be removed prior to chelation.

The CRL utilizes brushes, dental tools, and variable-speed pneumatic scribes to mechanically clean the timbers.

In some cases, the iron fasteners are too large to mechanically remove without damaging the wood. For these, we leave them be and let the timbers begin the chelation treatment. As the chelating chemicals begin to remove the iron from the wood, the large fasteners become loose and easier to remove.

After each timber is cleaned, the next stage is chemical chelation.   

Conservation Stages

Stage 1: Documentation
Stage 2: Mechanical Cleaning
Stage 3: Chemical Chelation
Stage 4: Bulking
Stage 5: Freeze Drying
Stage 6: Final cleaning and assembly


Monetary donations and volunteer workers are vital to the ongoing success of the Conservation Research Laboratory. If you would like to volunteer your time and expertise, please contact us here. If you would like to become one of our donors, please click the link below and direct your gift to: Center for Maritime Archaeology and Conservation.