How to use emory cloth, for your plumbing projects, is a good habit to get into. You want to use emory cloth, anytime you’re working with copper plumbing pipe…..or you’ll be sorry. “Joe” always carries a little emory cloth just in case he runs into a plumbing need. If you don’t know what emory cloth is, I guess you don’t do plumbing projects very often. You’ve got to get some emory cloth since you need to start doing some plumbing projects so you can save $$.