The removal of old varnish from an oil painting is one of the most fulfilling processes in the restoration of a picture. On a picture of more than twenty years of age it is likely that there will be several layers of old varnish, each layer having been put on top of the previous varnish and the dirt accumulated on it. The dirtiest pictures are those that have hung in rooms for many decades where there have been open fires and/or people smoking.
Having ensured that the painting is firmly and securely stretched, then tests can begin in and around the edges of a painting to find the best solvent to remove the old varnish and dirt. Photographs are taken at all stages of this work and at no time are any proprietary cleaners used. Many pictures have been irrevocably damaged by the indiscriminate experimentation of cleaning solvents.
An examination also takes place under longwave ultraviolet light which helps to determine whether there has been earlier restoration work or repainting of any part of the painted surface. At this stage in the process of researching the possibilities of cleaning, signatures and dates, if present can be noted and photographed.
Once the best solvent has been mixed and tested then cleaning can begin using cotton wool swabs and working on very small areas at any one time. Photographs show how progress is made over several days before cleaning is completed and then the picture is ready for varnishing.
"The removal of old varnish comes as a fulfilling process at the end of a deliberately painstaking journey of restoration."