Solder the Joint — Heat the Joint
Part of project
How to Solder Copper Pipes for a Permanent, Watertight Joint · Step 7 of 10
In this video
Light the propane torch and apply the flame directly to the body of the valve where it connects to the pipe. Heat the joint evenly. To check if it's hot enough, periodically touch the solder wire to the opposite side of the joint from the flame. When the joint is at the correct temperature, it will melt the solder instantly. Once it begins to melt, remove the flame and quickly run the tip of the solder around the entire seam. Capillary action will draw the molten solder into the joint, filling the gap and displacing the flux to create a solid, watertight seal.
Goal: Heat the joint and apply solder to create a permanent, watertight seal.
- Be extremely cautious when using the propane torch. Wear safety glasses and protect surrounding surfaces from the flame.
- Heat the fitting, not the solder. The hot fitting should melt the solder. This ensures the solder is wicked into the joint properly.
Used in this video
- Propane Torch (Tool Type: Plumbing Tools, Power Source: Manual) — To heat the pipe and valve for soldering.
- Safety Glasses — To protect eyes from potential solder splatter and the torch flame.
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FAQs
What are the most critical safety precautions I need to take when soldering copper pipes?
Always wear safety glasses and gloves to protect from heat and flux. Ensure adequate ventilation, keep a fire extinguisher or bucket of water nearby, and use a heat shield (like the Oatey 9 in. x 12 in. Hands-Free Solder Heat Shield) to protect surrounding flammable materials from the torch flame and hot pipes.
Why is cleaning and deburring the pipe and fitting so crucial before applying flux and soldering?
Thorough cleaning with a fitting brush and sandpaper removes oxides and contaminants, which are essential for the solder to properly flow and adhere via capillary action. Deburring with a tool like the Husky 1-5/8 in. Inner/Outer Reamer ensures the fitting seats correctly and prevents turbulence in water flow, promoting a perfect solder joint.
How do I know I'm using enough solder, and what commonly causes a joint to leak after soldering?
You've used enough solder when you see a complete, continuous ring of solder around the joint's circumference, indicating full capillary fill. Leaks are often caused by insufficient or uneven heat application, improperly cleaned surfaces, or applying too little solder, which results in an incomplete or 'cold' joint.
Can I use a regular propane torch, or do I need a MAPP gas torch for soldering copper pipes?
While a basic propane torch might suffice for smaller pipes (1/2" - 3/4"), a MAPP gas torch (such as the Flame King High Intensity Propane Torch Head) provides a hotter flame. This is more efficient for larger pipes and quicker heating, reducing the risk of overheating the pipe or burning off the flux prematurely, which are common beginner mistakes.
Solder the Joint — Heat the Joint
Part of project
How to Solder Copper Pipes for a Permanent, Watertight Joint · Step 7 of 10
In this video
Light the propane torch and apply the flame directly to the body of the valve where it connects to the pipe. Heat the joint evenly. To check if it's hot enough, periodically touch the solder wire to the opposite side of the joint from the flame. When the joint is at the correct temperature, it will melt the solder instantly. Once it begins to melt, remove the flame and quickly run the tip of the solder around the entire seam. Capillary action will draw the molten solder into the joint, filling the gap and displacing the flux to create a solid, watertight seal.
Goal: Heat the joint and apply solder to create a permanent, watertight seal.
- Be extremely cautious when using the propane torch. Wear safety glasses and protect surrounding surfaces from the flame.
- Heat the fitting, not the solder. The hot fitting should melt the solder. This ensures the solder is wicked into the joint properly.
Used in this video
- Propane Torch (Tool Type: Plumbing Tools, Power Source: Manual) — To heat the pipe and valve for soldering.
- Safety Glasses — To protect eyes from potential solder splatter and the torch flame.
Frequently Asked Questions
What are the most critical safety precautions I need to take when soldering copper pipes?
Always wear safety glasses and gloves to protect from heat and flux. Ensure adequate ventilation, keep a fire extinguisher or bucket of water nearby, and use a heat shield (like the Oatey 9 in. x 12 in. Hands-Free Solder Heat Shield) to protect surrounding flammable materials from the torch flame and hot pipes.
Why is cleaning and deburring the pipe and fitting so crucial before applying flux and soldering?
Thorough cleaning with a fitting brush and sandpaper removes oxides and contaminants, which are essential for the solder to properly flow and adhere via capillary action. Deburring with a tool like the Husky 1-5/8 in. Inner/Outer Reamer ensures the fitting seats correctly and prevents turbulence in water flow, promoting a perfect solder joint.
How do I know I'm using enough solder, and what commonly causes a joint to leak after soldering?
You've used enough solder when you see a complete, continuous ring of solder around the joint's circumference, indicating full capillary fill. Leaks are often caused by insufficient or uneven heat application, improperly cleaned surfaces, or applying too little solder, which results in an incomplete or 'cold' joint.
Can I use a regular propane torch, or do I need a MAPP gas torch for soldering copper pipes?
While a basic propane torch might suffice for smaller pipes (1/2" - 3/4"), a MAPP gas torch (such as the Flame King High Intensity Propane Torch Head) provides a hotter flame. This is more efficient for larger pipes and quicker heating, reducing the risk of overheating the pipe or burning off the flux prematurely, which are common beginner mistakes.