Soldering involves the heating of a filler metal to serve as a binder between two other metal pieces. While most solders are usually in wire or sheet form, silver solder paste with flux is a solder delivered in paste form for easy attachment to metal joints through spreading, eliminating the need to hold the solder and the soldering iron in place at the same time to apply. Instead, you simply spread the paste where needed, then heat it with a small torch to melt. The flux in the paste helps with the flow of the solder, while the silver in the paste forms a visually attractive silver line at the joints.
Things You'll Need
Dip the end of a toothpick into the silver solder paste with flux until you cover the end generously without the paste dripping from the toothpick. The added flux in the paste prevents oxidation of the metals that you're joining that can interfere with the attachment of the solder. It also serves as a wetting agent for the solder, causing it to flow over the joint with more fluidity, creating a smooth, even layer.
Spread the paste along the joint of the two pieces that you're soldering, using the toothpick. Cover the joint completely, transferring as much paste as necessary using the toothpick.
Light your torch and heat the pieces with the flame over the joint on both sides of the pieces.
Pass the flame over the solder paste, causing the solder to flow into the joints. The entire process will take just a few seconds to complete. Remove the flame and allow the joint to cool, hardening the solder.
Remove any flux remaining on the pieces by wiping the area with a cotton swab dipped in rubbing alcohol.
Correct solder mistakes by reheating the area with the iron to liquefy the solder and then using a toothpick to spread the liquid metal where you wish it to harden.