How to Solder Silver Plumbing

Silver solder copper fittings

The process of silver soldering is also known as hard soldering. Individuals who work with copper tubing or pipe learn the art of silver soldering. A proper silver solder weld will not allow the contents that flow through the copper pipe or tubing to escape. Learn how to silver solder by practicing at home on plumber's grade copper fittings and pipe. Make sure the silver solder has made a good seal by pouring water inside the copper and looking for drips at the seams.

Things You'll Need

• 1/2-inch rigid copper pipe
• 1/2-inch copper tees
• 1/2-inch copper coupling
• Acetylene torch
• Striker
• Bench vise
• 4-in-1 tubing brush
• Silver solder of Fil-flos
• Silver solder paste flux
• Stiff paintbrush
• Tube deburring tool
• Pipe cutter
• Emery cloth

Instructions

1. Cut a piece of 1/2-inch copper pipe 12 inches long using a pipe cutter. Place the pipe cutter on the pipe. Hand tighten the cutting wheels until they are firmly in the copper. Rotate the cutter around the circumference of the pipe until there is a score, or mark, in the pipe. Tighten the cutting wheels. Make one rotation. Repeat the process until the pipe is cut. Do not force the cut.

2. Remove the burs from the inside of the tube. Insert the deburring tool into the cut end of the pipe. Rotate the deburring tool to remove any burs.

3. Clean the outside of the copper pipe and the inside of one end of a tee fitting with a tube brush, then the emery cloth. Clean the area so it goes past the soldering area by 1 inch.

4. Dry-fit the tee to the copper pipe to make sure it fits securely.

5. Secure the pipe on a vertical plane in the bench vise so the cleaned end is facing out.

6. Brush the paste flux on the inside of the tee and the outside of the pipe until it is half an inch above the soldering line. Place the tee back on the pipe until it is in place.

7. Light the acetylene torch. Touch the tip of the flame to the joint, and rotate the flame around the pipe until the copper is red hot. Remove the flame from the copper pipe and fitting.

8. Touch the silver solder or Fil-flos on the top of the joint. The silver solder should instantly melt and follow the joint around the pipe. The pipe is not hot enough if the solder does not melt and flow.

Tips & Warnings

• Wrap a cool wet rag around the joint immediately after it is complete. This will help cool the pipe and make a professional looking joint.

• Fil-flos is significantly less expensive than silver solder and works the same.

References

• Google: Elkhart Products Corporation - Soldering and Brazing Copper Tube
• Ask the Builder: Soldering Copper Water Lines