Step 3 · Deburr and Clean the Pipe Ends
This is a non-negotiable step for a leak-free repair. After cutting, the pipe ends will have sharp burrs. Use a deburring tool (often integrated into a tubing cutter, or as a separate pen-style tool) to ream the inside and chamfer the outside of both pipe ends. This removes any sharp edges that could slice or damage the O-ring inside the push-to-connect fitting. Once deburred, take a piece of emery cloth or fine-grit sandpaper and thoroughly clean the outside surface of both pipe ends, extending about 1-2 inches from the end. You need to sand off all oxidation, dirt, and any residue until the copper is shiny and smooth. A perfectly clean and smooth surface is essential for the O-ring to create a durable, watertight seal.