Step 3 · Deburr and Clean the Pipe Ends
This is the most critical step for a leak-free repair. Take a deburring tool and insert it into the freshly cut pipe end, rotating it to remove the sharp burr on the inside edge. Then, use the outside portion of the tool to smooth the outer edge. Repeat for the other cut end. Next, take a piece of sandpaper or emery cloth and thoroughly clean the outside of both pipe ends, polishing the surface for at least one inch back from the cut. The copper should be shiny and completely free of any oxidation, paint, or grime. Finally, wipe the cleaned ends with a dry, clean cloth to remove all dust and copper particles.