Treating surface deformations and high raised cupping 

 

A color field painting by Michael Dailey, Spring Beach(1968) (oil on cotton canvas, 178.5 x 174 cm, private collection, Portland, Oregon, USA)presented23 crack patterns with pronounced cupping in the thick oil paint layer that were particularly disfiguring. The cracks were identified with raking light and mapped onto a transparent film [Gridley 2014]. In order to smooth the cupped cracks, humidity was applied locally via moistened blotters to the verso at crack sites, followed by AMH (38C - 43C) applied locally. Through the testing it was determined that the mild, steady and sustained heat transfer proved to be the critical element in the successful smoothing of the cupped paint film, which was ultimately applied for 30-40 minutes to relax the cotton duck canvas and soften the paint layers to smooth deformations. After smoothing, the most severely cupped sites were reinforced with application of gelatin to size the canvas verso in correspondence to the crack pattern, and was subsequently heated and then dried with blotters under heavy weight.