You may remember in my last post that I had taken a model in great need of conservation to the Lady Lever Art Gallery for demonstration purposes. The model had several snapped yards and masts, and missing blocks. Many people remarked on the blackness of the thick dirt, and how complicated the broken and twisted rigging was, and were interested to know how I would go about treating the model. As the treatment of the model has now been completed, I would like to share some of the treatment processes.
The first challenge was to carefully clean the model. This was more difficult than usual as the model had many small crevices and great care had to be taken to avoid the already damaged rigging. This was undertaken using small cotton wool swabs. Once the model was cleaned to an appropriate level I could then begin the very difficult process of untangling the threads of the rigging, and working out where each broken or missing rope needed to go. Fortunately I have learnt the arrangements and purposes of rigging and so it was not as complicated as it first appeared. Once the spars and yard arms had been re-joined (using wood pins and adhesive), the rigging could be repaired. Where possible, I saved the original thread, attaching it to new cotton thread at the breakages. In some areas the threads were too friable and needed to be replaced.
The silk flag also required conservation and so was removed. It was very stiff and bent, so I decided to re-humidify it using a sandwich of damp bloating paper, gortex, the flag, and then the same arrangement on the other side. This flattened the flag well. It was still very dirty and so after testing; I cleaned it by soaking in a solution of 5% tri-ammonium citrate (a chelating agent) in water. The silk itself was fragile, and to ensure that it was strong enough to place back onto the model I mounted it onto dyed silk crepeline.
The last problem to address on the model was the lead disease of the fittings on the baseboard. This was crumbling white corrosion product that I removed mechanically under a microscope, before coating with a protective coating. After making replica blocks for the anchor and reattaching the flag to the flag staff, the model was complete and now looks like an impressive ship of war.
See a larger version of the image above on Flickr to see more detail.
Update: 20/02/2012: See more photos of the model on our Flickr set of before and after conservation.