Wayne, the secret is, the lip never gets dirty cause its covered with tape, so there is no dirty lip for the tape to stick to,,
oh you mean you have a gallon that is already dirty,, tsk tskk, see what happens when you build so fast, n1you get ahead of my great advice,, no slow down,, like me,, and the 109,,
actually, it does stick just fine assuming the paint on the lip is dry