Tack Cloth

A tack cloth is a cloth treated with a slightly sticky (tacky) resin, wiped lightly across a sanded surface immediately before applying finish to lift fine dust a vacuum or dry rag can't fully remove. Even dust invisible to the eye can settle into wet finish and dry as a rough, gritty texture, which is exactly the problem a tack cloth's final pass is meant to prevent -- it's a last step immediately before finish goes on, not a general shop cleaning tool, since the tacky residue it leaves is meant to be sealed under finish, not left exposed.