How to Solder on Aluminum
- 1). Join the ends of the aluminum together.
- 2). Start the blowtorch and place the end of the alloy rod into the flame to heat it. The alloy rod is the material used to solder the joints together.
- 3). Dip the end of the alloy rod into flux. This is a chemical cleansing agent that removes materials from the alloy rod that can cause corrosion.
- 4). Run the flame of the blowtorch over the section of aluminum that is being soldered together to heat it up.
- 5). Wipe the flux on the end of the alloy rod around the joint until it becomes watery and thin.
- 6). Position the blowtorch so the flame is against the opposite side of where you are applying the alloy. Hold the end of the alloy rod against the aluminum over the joint until it melts and fuses the different pieces together. Allow the aluminum to cool. Inspect the joint, and solder it again if needed.
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