I am repainting a bronze memorial sign. Stripped a zillion coats of paint and poished the raised letters. I am now masking the raised letters with the intent to spary the background, then remove the letter masking leaving a sign with polished bronze letters over a dark green painted background. I was using 3m blue masking tape, then a razor knife to trm out the letters. It is not working as it appears the blue 3m tape does not have enough stickum to stay tight to the 1/4 wide letters. Any suggestions on a better product? thanks