I did just this a few years ago to my cedar-canvas, but it is only a temporary measure. The root of the problem is the filler in the canvas. After a certain period of time it cracks, and then just keeps cracking and cracking. Every winter (maybe due to the cold) mine develops new cracks. Every spring I put off having it re-canvassed and sand it down and paint it again

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The only real solution is new canvas (and filler and paint). I was told by one workshop that a canvas lasts typically 10 years (mine, I believe, has lasted 30 years with a bit of help). Cost of professional recanvassing etc. is around CDN $600.