Dilute the flux to the recommended concentration if necessary. Brush flux onto the area to be repaired. Heat the area for 3 to 5 seconds with the hot inner flame. Brush flux onto the area again. Heat the area with the soft outer flame while touching the solder to the heated metal surface.
Tips Be sure the area is clean before fluxing.
If the solder fails to flow or the metal turns dark, you are using too much heat. Allow the metal to cool, reflux the area and adjust the flame lower or hold the torch further from the work. ZERO-ZINC fluxes perform differently than zinc chloride fluxes, so a little practice may be needed to perfect your technique. ZERO-ZINC fluxes perform better with high tin solders than high lead solders. The information presented herein is our interpretation of certain test results and field experience to date.