You cannot effectively solder copper pipe with a standard soldering iron. Soldering copper pipe requires significantly more heat than a soldering iron can provide. A propane torch is the appropriate tool for this task.
Why a Soldering Iron Won't Work for Copper Pipe
The primary reason a soldering iron is unsuitable for soldering copper pipe is insufficient heat. Copper is an excellent conductor of heat, meaning it quickly dissipates heat applied to it. A soldering iron simply cannot generate and maintain the high temperature needed to bring the copper pipe and fitting to the correct temperature for solder to melt and flow properly into the joint. This proper "tinning" ensures a strong and leak-free seal.
The Correct Method: Using a Propane Torch
To solder copper pipe correctly, you'll need a propane torch and solder specifically designed for plumbing applications. Here's a brief overview of the process:
- Preparation is Key: Clean the outside of the pipe and the inside of the fitting with a wire brush or emery cloth. This removes oxidation and allows the solder to bond correctly.
- Apply Flux: Apply flux to both the pipe and the fitting. Flux cleans the metal further during heating and helps the solder flow into the joint.
- Assemble the Joint: Slide the fitting onto the pipe.
- Heat the Joint: Using a propane torch, heat the fitting evenly. Focus the flame primarily on the fitting, as it is typically thicker than the pipe. Move the torch around the fitting to ensure even heating.
- Apply Solder: Once the fitting is hot enough (test by briefly touching the solder to the joint; it should melt readily), apply the solder to the joint where the pipe and fitting meet. The heated pipe and fitting should melt the solder, drawing it into the joint by capillary action.
- Let it Cool: Allow the joint to cool naturally. Avoid moving or disturbing the joint while it cools.
- Clean Up: Once cooled, wipe away any excess flux or solder.
Important Safety Note: Always exercise caution when using a propane torch. Wear safety glasses and gloves, and work in a well-ventilated area. Keep a fire extinguisher nearby.
In summary, while soldering irons are suitable for electronics and other small tasks, they lack the necessary heat for soldering copper pipe. A propane torch is the required tool for creating strong, leak-proof copper pipe joints.
