If I care enough about maintaining a sharp edge between painted and varnished surfaces to use masking tape, I sure don’t want to peel off the tape and discover that the paint has seeped under the tape and left a fuzzy edge. To prevent this problem, I apply the masking tape as usual, being sure to press down the edge with a putty knife. Then I go one step further and brush a layer of clear shellac against the tape edge to seal it. Then I paint. Super-sharp edges remain.
Jason McKay, Portland, OR
From Fine Homebuilding 226, pp. 26
March 8, 2012