ART GUIDE



art guide

Conservation and Treatment of Oil Paintings



E. Weak Canvas

Sometimes a canvas grows too weak to support itself. In such cases it is necessary to reline the picture that is to attach fabric at the back of the original one with an adhesive. When the fabric gets weak, it may show small tears at the edges and plainly look too fragile to be hung or moved. Causes

  • Improper stretching : This causes undue stress on the canvas, which in time, causes the fabric to start giving way at the edges.
  • Sometimes the artist uses a weak fabric to begin with. With the passage of time, the canvas only gets more fragile not being able to maintain its own weight on a stretcher.


Treatment

The relining treatment is more or less standard and briefly takes the following procedure :

  1. Application of a paper to the face of the picture with a light paste adhesive. This is called "facing' and it serves to protect the paint layer during the lining process.
  2. Removal of the old relining fabric , mechanical cleaning of the reverse of the original fabric support.
  3. Attachment of relining fabric to the original fabric with an adhesive. Some commonly used adhesives are wax, glue/paste, heat activated adhesives such as Beva 371 and various Plextols. Chief considerations in the choice of the adhesives are required, strength of the new bond between the canvases, the maximum temperature that will not harm the paint, and the effect of the adhesive on the appearance of the painting. The type of adhesive would determine the process of application. For instance, a thermoplastic adhesive(e.g.Beva 371) is applied to the lining canvas in a viscous state and allowed to dry. Then the reverse of the damaged painting is placed in contact with the coated lining canvas and subjected to controlled heat and pressure for the adhesive bond to form.
  4. Stretching of the lined painting, removal of facing, and further steps in the conservation treatment as required.


Sometimes a painting in otherwise good condition cannot be stretched because its tacking edges are weak or broken. Adequate support can be provided with the addition of a strip lining along the edges. The procedure involves attaching thin fabric strips to the tacking edges of the painting itself.

fig 1. Example of a weak
canvas requiring relining.