The Blue Whale

We have started on work on the largest of the whale skeletons housed in the hall - the huge Blue whale. The process of cleaning, repairing and restoring process has begun on the massive skull and mandibles of this rare specimen. It is clear that over the years many repairs have been carried out on this skeleton, particularly in the region of the base of the skull and maxilla. Whereas some areas of bone have been skilfully replaced by wood there is also much plaster and paint which has been applied to various areas and is ugly and visible. Of course, there is also the layer of oil, dirt and dust that afflicts all the bones in the collection.An example of the paint, plaster, fragile bone and old repairs on the surface of the the Blue whale maxilla.
An initial test clean showed that although the wet cleaning techniques used previously would be suitable for the mandibles (lower jaws) and some areas of the skull, the thick plaster and paint layers would be harder to remove and required a different cleaning method.

Wet cleaning of the Blue whale right mandible. The results can clearly be seen.

It was decided that some of the plaster could be gently chipped off by hand and that sand blasting would be used to for the stubborn paint, dirt and oil on the under surface of the maxilla.

Although sand blasting sounds like a very harsh technique to use on old whale bone it can be modified by both the substrate used and the air pressure to be quite gentle. For these purposes a relatively low air pressure was used to ensure that only the dirt and paint and no surface bone was removed.

Carefully chipping away at the plaster on the ventral surface of the maxilla.

Using the sand blasting machine to clean the paint, plaster residue, dirt and oil from the maxilla.

The results of a sand blast cleaning a strip of the maxilla. As you can see it was very effective.

A comparison between the cleaned (left of picture) and un cleaned Blue whale skull base.

A comparison between the cleaned (left of picture) and un cleaned Blue whale maxilla.

The results of the combination of wet cleaning and sand balsting on the Blue whale skull and mandibles have been amazing - the rather dark, dirty, painted and platered bones have been transformed.