At various points in a furniture object's life it is typically given a new surface coating, either to mask damage, conform with changing aesthetics or provide additional protection. This practice may distort the object's original meaning and can make it difficult to appreciate its intended aesthetics. Here is an object we were able to free from an obscuring later overcoat, but not without overcoming a significant technical challenge first.
At some point during the long life of this object, it was given an overall coating, which darkened the patina to a very murky orange and obscured the delicate penwork painting that defined the piece when it was made. For aesthetic reasons, the owner wished to have the disfiguring coating removed. This had to be done very delicately; the solvent we needed to use to dissolve the coating would also dissolve the penwork surface painting.
In order to remove the overcoating without damaging the underlying painting, we needed a technique that would penetrate only enough to soften it for removal. Essentially, we wanted it to come in contact only with the solvent vapor, and not with liquid solvent. To accomplish this, we gelled a specifically formulated solvent, and then utilized a gel pack technique to suspend it over the surface. The solvent itself never touched the surface, but its vapor acted over time to soften the overcoating so we could remove it.
Without the dark overcoating, the fine penwork is far more visible and the table looks more as it was originally intended to look.